40 results on '"Yang, Zichen"'
Search Results
2. Effect of the Fiber Diameter of Polyamide 11 Nanofibers on Their Internal Molecular Orientation and Properties.
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Yang, Zichen, Takarada, Wataru, and Matsumoto, Hidetoshi
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POLYAMIDES , *MOLECULAR orientation , *POLYAMIDE fibers , *NANOFIBERS , *CRYSTAL orientation , *HYDROGEN bonding - Abstract
Herein, the effect of the diameter of polyamide 11 nanofibers (PA11 NFs) on their internal structures as well as thermal and mechanical properties is investigated. Aligned PA11 NFs with diameters ranging from 109 to 462 nm are prepared by the single‐component solvent electrospinning of different PA11/1,1,1,3,3,3‐hexafluoro‐2‐propanol (HFIP) solutions (4–8 wt%) and subsequently characterized. Owing to the similar hydrogen bond formation within the NFs during electrospinning, all prepared NFs have δ'‐phase crystals with similar crystallinities and crystallite sizes. However, the orientation of the δ'‐phase crystals is disrupted in NFs with diameters less than 200 nm, due to the rapid solidification during electrospinning. The δ'‐phase crystals are the most highly oriented within NFs having a fiber diameter of ≈300 nm, and the corresponding NF sheets exhibit the highest mechanical strength. A single PA11 NF with a fiber diameter of ≈300 nm also exhibits a good piezoelectric response (piezoelectric coefficient d33 = 2.1 pm V–1). [ABSTRACT FROM AUTHOR]
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- 2023
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3. A Sensitive Surface-Enhanced Raman Spectroscopy Method for Detecting Tetracycline in Milk.
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Yang, Zichen, Ma, Chaoqun, Gu, Jiao, Wu, Yamin, Zhu, Chun, Li, Lei, Gao, Hui, Zhang, Ye, Shang, Yunpeng, Wang, Chengwei, and Chen, Guoqing
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TETRACYCLINES , *SERS spectroscopy , *TETRACYCLINE , *MILK - Abstract
Tetracycline, an animal antibiotic, may remain in milk to cause harm to human health. For economic reasons, the abuse of antibiotics is becoming more and more common. Therefore, the abuse of tetracycline has alarmed the dairy industry and many countries such as New Zealand, China, and the USA have proposed strict standards. Surface-enhanced Raman scattering (SERS) is an emerging detection method which has been applied in food detection with the advantages of no complex pretreatment, fast detection, and weak water environment interference. Considering the abuse of antibiotics in dairy industry, we used polydimethylsiloxane (PDMS) plasma cavity as SERS substrate to detect tetracycline in milk. We found that the enhancement ability of PDMS substrate is affected by addition of 4-amino-1-butanol and complex interplay in the milk--tetracycline system. The modified PDMS plasma cavity has high SERS sensitivity that allows us to achieve low detection limit of 0.28 μ g/L. The correlation coefficient was 0.987. The detection of tetracycline in milk using PDMS substrate is quick (within 10 min) and it provides a possible method for in-site detection of tetracycline. [ABSTRACT FROM AUTHOR]
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- 2021
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4. Urinary neonicotinoids and metabolites are associated with obesity risk in Chinese school children.
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Yang, Zichen, Wang, Yuanping, Tang, Chuanxi, Han, Minghui, Wang, Yi, Zhao, Ke, Liu, Jiaqi, Tian, Jiacheng, Wang, Hexing, Chen, Yue, and Jiang, Qingwu
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NEONICOTINOIDS , *GENERALIZED estimating equations , *SCHOOL children , *METABOLITES , *CHILDHOOD obesity , *SCREEN time , *IMIDACLOPRID - Abstract
• Neonicotinoids and metabolites in urine were overall detected in 80.3% of children. • Urinary neonicotinoids varied with sex, age, family type, father's BMI, and screen time. • Exposure to acetamiprid was negatively associated with BMI z-score. • Combined exposure to neonicotinoids was positively associated with childhood obesity. • Some associations showed age- and sex-related differences. Neonicotinoids are the most widely used insecticides. Laboratory studies have suggested that neonicotinoids are one potential obesogen, but relevant data are limited in human. To examine the association between exposure to neonicotinoids and childhood obesity. We investigated 442 children in Shanghai, East China and measured eight neonicotinoids (thiamethoxam, clothianidin, acetamiprid, imidacloprid, thiacloprid, nitenpyram, dinotefuran, and imidaclothiz) and four metabolites (N-desmethyl-thiamethoxam, N-desmethyl-clothianidin, N-desmethyl-acetamiprid, and 5-OH-imidacloprid) in urine. Body mass index (BMI) and waist circumference (WC) were used to identify general overweight/obesity and central obesity, respectively. Linear and logistic regression models based on generalized estimating equations were used to investigate the associations of urinary neonicotinoids and metabolites with BMI z-score, WC z-score, general overweight/obesity, and central obesity. Children with a positive detection of clothianidin and its metabolite had a marginally higher BMI z-score (regression coefficient (β): 0.08, 95% confidence interval (95% CI): 0.01, 0.14) after adjusted for relevant covariates. After creatinine-adjusted concentration was trichotomized, compared to children with a negative detection, children in the high urinary concentration of acetamiprid and its metabolite had a low BMI z-score (β: −0.19, 95%CI: −0.30, −0.08), children in the medium urinary concentration of neonicotinoids and metabolites other than thiamethoxam, clothianidin, acetamiprid, and their metabolites had a marginally higher BMI z-score (β: 0.25, 95%CI: 0.03, 0.46), a higher WC z-score (β: 0.24, 95%CI: 0.14, 0.33), and a higher odds of central obesity (odds ratio (OR): 2.16, 95% CI: 1.28, 3.63), and children in the medium urinary concentration of all neonicotinoids and metabolites had a higher odds of central obesity (OR: 1.55, 95%CI: 1.04, 2.33). Some associations showed sex- and age- related differences. Urinary neonicotinoids and metabolites were found to be differently associated with obesity-related indexes, which suggested that exposure to neonicotinoids might have a mixed effect on childhood obesity. [ABSTRACT FROM AUTHOR]
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- 2024
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5. Sensitive Determination of Stevioside by Surface-Enhanced Raman Spectroscopy (SERS) Using 4-Mercaptophenylboric Acid Functionalized Silver Nanoparticles (Ag NPs).
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Guan, Weinan, Chen, Guoqing, Yang, Zichen, Shen, Jialu, Yang, Taiqun, Ma, Chaoqun, Li, Lei, Gao, Hui, Xiong, Yi, Zhu, Chun, Zhou, Yan, and Zhang, Wei
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Stevioside is an important natural sweetener in food and beverages. There are concerns about its safety, but few methods for its determination. Silver nanoparticles (Ag NPs) functionalized with 4-mercaptophenylboronic acid (4-MPBA) were successfully used to determine stevioside in beverages based upon surface-enhanced Raman spectroscopy (SERS). The Ag NPs self-assemble with 4-MPBA through the covalent interaction of their sulfhydryl groups with the metal particles. Boronic acid groups bonded to 1,2-/1,3-diol groups form cyclic boronic esters with strong affinity and significant specificity for stevioside. The combination of the two leads to an alteration of the 4-MPBA vibrational mode. The change in the orientation of the moiety and the charge transfer resulted in a significant increase of the SERS signal. The substrates showed strong specificity and sensitivity to stevioside in the presence of other sweeteners. Also, the substrate modification conditions were optimized, including the time, ratio, and concentration. The limit of detection (LOD) for stevioside in beverages was 0.210 μmol/L, and the recovery was from 98.4% to 109.4%. In summary, the presented SERS method provides high sensitivity for stevioside. [ABSTRACT FROM AUTHOR]
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- 2024
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6. Nanotechnology-enabled M2 macrophage polarization and ferroptosis inhibition for targeted inflammatory bowel disease treatment.
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Zhao, Yuge, Yin, Weimin, Yang, Zichen, Sun, Jiuyuan, Chang, Jiao, Huang, Li, Xue, Liangyi, Zhang, Xiaoyou, Zhi, Hui, Chen, Shiyu, Chen, Nana, and Li, Yongyong
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INFLAMMATORY bowel diseases , *THERAPEUTICS , *MACROPHAGES , *REACTIVE oxygen species , *LIPOSOMES , *NANOMEDICINE - Abstract
Transforming macrophages into the anti-inflammatory M2 phenotype could markedly strengthen inflammatory bowel disease (IBD) treatment, which is considered as a promising strategy. However, the high ferroptosis sensitivity of M2 macrophages, which decreases their activity, is a major stumbling block to this strategy. Therefore, promoting M2 polarization while simultaneously inhibiting ferroptosis to tackle this challenge is indispensable. Herein, a calcium‑carbonate (CaCO 3) mineralized liposome encapsulating a ferroptosis inhibitor (Fer-1) was developed (CaCO 3 @Lipo@Fer-1, CLF). The CaCO 3 mineralized coating shields the liposomes to prevent the release of Fer-1 in circulation, while releasing Ca2+ in the acidic-inflammatory environment. This released Ca2+ promotes M2 polarization through the CaSR/AKT/β-catenin pathway. The subsequently released Fer-1 effectively upregulates GSH and GPX4, scavenges reactive oxygen species, and inhibits ferroptosis in M2 macrophages. In vivo, CLF improved the targeting efficiency of IBD lesions (about 4.17-fold) through the epithelial enhanced permeability and retention (eEPR) effect and enhanced IBD therapy by increasing the M2/M1 macrophage ratio and inhibiting ferroptosis. We demonstrate that the synergistic regulation of macrophage polarization and ferroptosis sensitivity by this mineralized nanoinhibitor is a viable strategy for IBD therapy. Schematic diagram of the preparation of CaCO 3 @Lipo@Fer-1 (CLF) mineralized-liposome and therapeutic mechanisms in inflammatory bowel disease (IBD). (A) Preparation of CLF mineralized liposome. (B) CLF treats IBD by regulating macrophage polarization and inhibiting ferroptosis. (C) Mechanism of CLF promoting polarization and inhibiting ferroptosis of M2 macrophages. [Display omitted] [ABSTRACT FROM AUTHOR]
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- 2024
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7. A hydrogen bonding based SERS method for direct label-free L-hydroxyproline detection.
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Yang, Zichen, Chen, Guoqing, Shen, Jialu, Ma, Chaoqun, Gu, Jiao, Zhu, Chun, Li, Lei, and Gao, Hui
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HYDROGEN bonding , *SERS spectroscopy , *SMALL molecules , *HYDROGEN bonding interactions , *DAIRY products , *CHARGE transfer , *MILK proteins - Abstract
[Display omitted] • This paper presents a sensitive and label-free SERS method that requires no pre-derivatization and adjustment of pH for L-Hyp detection. • The mechanism of this work provides inspiration for detecting molecules with small Raman cross-section. • The proposed SERS method has a low LOD of 8.18 ng/mL in aqueous solution and 0.13 μg/mL in milk. The detection of non-protein nitrogen adulterants is a major challenge in dairy testing. As a marker molecule of animal hydrolyzed protein, the presence of non-edible L-hydroxyproline (L-Hyp) molecules can be used to identify low-quality milk containing components of animal hydrolyzed protein. However, it is still difficult to detect L-Hyp directly in milk. The Ag@COF-COOH substrate in this paper can be used to realize label-free L-Hyp sensitive detection based on the hydrogen bond transition mechanism. To explore the mechanism, the binding sites of hydrogen bond interaction have been verified experimentally and computationally, and the charge transfer process was also explained in terms of HOMO/LOMO energy level. In conclusion, the quantitative models for L-Hyp in an aqueous environment and in milk were developed. The limit of detection (LOD) of L-Hyp in an aqueous environment could reach 8.18 ng/mL, with R2 of 0.982. The linear range of quantitative detection in milk was 0.5–1000 μg/mL and the LOD was as low as 0.13 μg/mL. In this work, a hydrogen bond interaction based Surface-enhanced Raman spectroscopy (SERS) method for the label-free detection of L-Hyp was proposed, which complemented the application of SERS technology in the detection of dairy products. [ABSTRACT FROM AUTHOR]
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- 2023
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8. Magnetic Fe3O4@COF@Ag SERS substrate combined with machine learning algorithms for detection of three quinolone antibiotics: Ciprofloxacin, norfloxacin and levofloxacin.
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Yang, Zichen, Chen, Guoqing, Ma, Chaoqun, Gu, Jiao, Zhu, Chun, Li, Lei, and Gao, Hui
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MACHINE learning , *CIPROFLOXACIN , *SERS spectroscopy , *NORFLOXACIN , *ANTIBIOTICS , *MOLECULAR structure - Abstract
Quinolone antibiotics have good antibacterial properties and are commonly used antibiotics in the dairy industry. Currently, the problem of excessive antibiotics in dairy products is very serious. As an ultra-sensitive detection technology, Surface-Enhanced Raman Scattering (SERS) was applied to the detection of quinolone antibiotics in this work. In order to classify and quantify three antibiotics (Ciprofloxacin, Norfloxacin, Levofloxacin) with highly similar molecular structures, a combination of magnetic COF-based SERS substrate and machine learning algorithms (PCA-k-NN, PCA-SVM, PCA-Decision Tree) was used. The classification accuracy of the spectral dataset could reach 100% and the results of LOD calculation were: CIP: 5.61 × 10−9M, LEV: 1.44 × 10−8M, NFX: 1.56 × 10−8M. This provides a new method for the detection of antibiotics in dairy products. [Display omitted] • This method realized the detection of three quinolone antibiotics with one SERS substrate. • This method can classify three quinolone antibiotics with highly similar molecular structures with 100% accuracy. • The proposed SERS method has low LODs in milk: CIP: 5.61 × 10−9M, LEV: 1.44 × 10−8M, NFX: 1.56 × 10−8M. [ABSTRACT FROM AUTHOR]
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- 2023
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9. Characterization and genome annotation of a newly detected bacteriophage infecting multidrug-resistant Acinetobacter baumannii.
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Yang, Zichen, Liu, Xinzhu, Shi, Yunlong, Yin, Supeng, Shen, Wei, Chen, Jing, Chen, Yu, Chen, Yajie, You, Bo, Gong, Yali, Luo, Xiaoqiang, Zhang, Cheng, Yuan, Zhiqiang, and Peng, Yizhi
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ACINETOBACTER baumannii , *BACTERIOPHAGES , *CIRCULAR DNA , *SEWAGE purification , *TRANSMISSION electron microscopy , *NUCLEOTIDE sequencing - Abstract
A novel virulent bacteriophage, φAbp2, infecting multidrug-resistant (MDR) Acinetobacter baumannii was isolated from the wastewater of a sewage management centre at Southwest Hospital, China. Transmission electron microscopy and phylogenetic analysis revealed that φAbp2 belongs to the subfamily Peduovirinae. A one-step growth curve demonstrated that φAbp2 had a latent period of 15 min, a lysis period of 35 min, and a burst size of 222 particles per infected host cell. Moreover, φAbp2 showed a relatively broad host range in local A. baumannii, and it also exhibited tolerance over a wider range of thermal and pH conditions. Genomic sequencing revealed that φAbp2 has a circular double-stranded DNA genome with no sequence similarity to our previously isolated φAbp1. Eighty-eight putative open reading frames (ORFs) encoding 41 proteins of known function and 47 of unknown function were identified, and the G/C content was 37.84%. φAbp2 is a new member of the subfamily Peduovirinae of the family Myoviridae. Its genome sequence is very similar to that of the A. baumannii phage LZ35. [ABSTRACT FROM AUTHOR]
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- 2019
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10. Deep Rotation Equivariant Network.
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Li, Junying, Yang, Zichen, Liu, Haifeng, and Cai, Deng
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REPRESENTATION theory , *MATHEMATICAL convolutions , *ARTIFICIAL neural networks , *DEEP learning , *MATHEMATICAL analysis - Abstract
Recently, learning equivariant representations has attracted considerable research attention. Dieleman et al. introduce four operations which can be inserted into convolutional neural network to learn deep representations equivariant to rotation. However, feature maps should be copied and rotated four times in each layer in their approach, which causes much running time and memory overhead. In order to address this problem, we propose Deep Rotation Equivariant Network consisting of cycle layers, isotonic layers and decycle layers. Our proposed layers apply rotation transformation on filters rather than feature maps, achieving a speed up of more than 2 times with even less memory overhead. We evaluate DRENs on Rotated MNIST and CIFAR-10 datasets and demonstrate that it can improve the performance of state-of-the-art architectures. [ABSTRACT FROM AUTHOR]
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- 2018
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11. Detection of melamine by using carboxyl-functionalized Ag-COF as a novel SERS substrate.
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Yang, Zichen, Ma, Chaoqun, Gu, Jiao, Wu, Yamin, Zhu, Chun, Li, Lei, Gao, Hui, Yin, Wenzhi, Wang, Zirui, and Chen, Guoqing
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SERS spectroscopy , *MELAMINE , *KIDNEY stones , *DAIRY products - Abstract
• The novel Ag-COF-COOH substrates provide huge SERS hot spots, EF = 9.72 × 106. • The SERS method in this work is sensitive and the LOD is 0.68 μg/L in milk. • The SERS method in this work requires only one step of pretreatment. Melamine, a nitrogen-containing organic molecule, has received widespread attention as it had been illegally added in dairy products to increase the content of nitrogen, leading to kidney stones in healthy people after long-term ingestion. Based on SERS technology and Covalent Organic Framework (COF) materials, we developed carboxyl-functionalized Ag-COF-COOH materials as SERS substrates for the detection of melamine adulteration. Using COF material as a ligand can effectively reduce the influence of interferents in milk. In addition, we investigated two causes of melamine SERS enhancement: the ordered arrangement of Ag NPs and the strong interaction between the substrate and the melamine. The linear range was 1–20 μg/L and the limit of detection (LOD) was 0.68 μg/L in liquid milk due to the high sensitivity and reliability of this method. The results show that this new SERS substrate has great potential for applications in the food surveillance industry. [ABSTRACT FROM AUTHOR]
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- 2023
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12. SERS Detection of Benzoic Acid in Milk by Using Ag-COF SERS Substrate.
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Yang, Zichen, Ma, Chaoqun, Gu, Jiao, Wu, Yamin, Zhu, Chun, Li, Lei, Gao, Hui, Yin, Wenzhi, Wang, Zirui, Zhang, Ye, Shang, Yunpeng, Wang, Chengwei, and Chen, Guoqing
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BENZOIC acid , *SERS spectroscopy , *MILK , *DAIRY products , *ACETIC acid , *MATERIALS analysis , *FOOD additives - Abstract
[Display omitted] • COF (covalent-organic framework) capped with sliver nanoparticles (Ag NPs) were first developed as SERS substrate for detection of benzoic acid in liquid milk. • This detection method has high sensitivity and reliability that allows us to achieve LOD of 0.13μg/mL in milk and 0.00372μg/mL in water. • The proposed method can be applied in the detection of real milk samples. Benzoic acid, which has a pivotal role in food additive, is prohibited to add as a preservative in dairy products. China, Brazil, and other countries have proposed standard methods to detect the addition of benzoic acid in food. Surface-enhanced Raman scattering (SERS) is an upcoming spectral detection technique, which has been widely used in the field of material analysis with the advantages of non-invasive, fast detection speed and complex environment with little interference. To detect the illegal use of benzoic acid in dairy industry, we developed Ag-COF (covalent-organic framework) material as SERS substrate to detect benzoic acid in liquid milk. The great enhancement ability of Ag-COF substrate is controlled by the addition of acetic acid and complex interplay between COF material and benzoic acid. This detection method has high sensitivity and reliability that allows us to achieve limit of detection (LOD) of 0.13 μg/mL in milk and 0.00372 μg/mL in water by applying this method. In experiment on recovery rate of real samples, the detection time is less than 15 minutes and the relative standard deviation (RSD) ranged from 2.82% to 5.69%. Therefore, this method has practical significance of the detection of benzoic acid in dairy products. [ABSTRACT FROM AUTHOR]
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- 2022
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13. Computational design of a chitosan derivative for improving the color stability of anthocyanins: Theoretical calculation and experimental verification.
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Ai, Xin, Pan, Fei, Yang, Zichen, Li, Jiayi, Tuersuntuoheti, Tuohetisayipu, Wang, Ou, Zhao, Lei, and Zhao, Liang
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MOLECULAR dynamics , *CHITOSAN , *ORGANIC acids , *ANTHOCYANINS , *HYDROPHOBIC interactions , *QUANTUM mechanics - Abstract
The objective of this study was to design a chitosan (CS) derivative with good protective effect on the color stability of anthocyanins (ACNs) under accelerated storage. The binding affinities and interactions of 12 organic acids with cyanidin-3-O-glucoside (C3G) were evaluated using quantum mechanics method. Sinapic acid (SinA) showing the strongest interaction with C3G was selected for the synthesis of SinA-grafted-CS (SinA-g-CS), which was further characterized by FTIR and 1H NMR. Under accelerated storage conditions (40 °C), SinA-g-CS significantly improved the color stability of black rice anthocyanins (BRA) in the presence of l -ascorbic acid (pH 3.0), and showed a better protective effect than that of CS. Moreover, molecular dynamics simulation analysis showed SinA-g-CS formed more hydrogen bonds with C3G than CS. Our study demonstrated that SinA-g-CS designed by computational methods can effectively protect ACNs from degradation, and has the potential to be used in ACN-rich beverages as a replacement for CS. [Display omitted] • Sinapic acid (SinA) was screened through QM calculations for chitosan modification. • SinA-grafted-chitosan conjugate (SinA-g-CS) was prepared and characterized. • SinA-g-CS improved color stability of anthocyanins (ACNs) during accelerated storage. • SinA-g-CS can form more hydrophobic interactions with ACNs than CS. [ABSTRACT FROM AUTHOR]
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- 2022
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14. Construction of QSAR model based on cysteine‐containing dipeptides and screening of natural tyrosinase inhibitors.
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Li, Xiaofang, Pan, Fei, Yang, Zichen, Gao, Feng, Li, Jiawei, Zhang, Feng, and Wang, Tegexibaiyin
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PHENOL oxidase , *QSAR models , *DIPEPTIDES , *MOLECULAR dynamics , *HUNTINGTON disease , *MEDICAL screening - Abstract
Considering that natural products as tyrosinase inhibitors are considered to be safe, with little or no toxic side effects and friendly to the environment, it is urgent to develop a new recognition strategy for natural tyrosinase inhibitors. In current study, an integrated computational analysis was conducted on Cys‐containing dipeptides with high tyrosinase inhibitory activity. Firstly, molecular fingerprint similarity (FS) clustering analysis was performed on the target molecule using machine learning. Secondly, genetic algorithm was used to construct two kinds of highly accurate QSAR models (R2 =.978 and.984, respectively) with Cys at C‐terminal and N‐terminal. Finally, three novel natural candidate inhibitors (NP1, NP2, NP3) were discovered using Molnatsim natural product cluster library, automated screening process and QSAR based on the maximum common substructure (MCS) algorithm, their IC50pre were 260.96, 3.37 and 0.05 μm/mol. Pharmacokinetic predictions showed that NP2 and NP3 had high Bioavailability Score (BS) and Gastrointestinal (GI) absorption, and molecular dynamics simulations further validated the stability of these novel natural candidate inhibitors in binding to tyrosinase. In conclusion, our results provide new ideas for discovering new activities of natural products, and provide an accurate QSAR model for developing novel tyrosinase inhibitors based on MCS Cys‐containing dipeptides. Practical applications: Tyrosinase is related to the occurrence of diseases such as excessive melanin deposition such as freckles and chloasma, and studies have shown that neurodegeneration associated with Parkinson's disease and Huntington's disease is also related. In addition, enzymatic browning on the surface of fresh fruit and vegetable slices will shorten the shelf life and affect their quality. Therefore, screening, designing and developing efficient tyrosinase inhibitors is very important in the fields of medicine, cosmetics, food and so on. [ABSTRACT FROM AUTHOR]
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- 2022
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15. Erythrocyte‐Derived Bioactive Nanovesicles Reverse the Immunosuppressive Function of Adenosine for Tumor Photoimmunotherapy.
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Sun, Jiuyuan, Liu, Yiqiong, Zhao, Yuge, Yin, Weimin, Yang, Zichen, Chang, Jiao, Huang, Li, Chen, Shiyu, Zhi, Hui, Xue, Liangyi, Zhang, Xiaoyou, Dong, Haiqing, and Li, Yongyong
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Adenosine has garnered significant attention as a potential target for overcoming tumor immune evasion. It exacerbates the immunosuppressive tumor microenvironment (TME) by incapacitating various protective immune cells. However, inhibitors targeting adenosine receptors are limited by incomplete blockade effects and off‐target toxicity, necessitating the exploration of more effective strategies. Inspired by the native biologic function of adenosine deaminase (ADA) in hydrolyzing adenosine, a bioactive catalytic nanovesicle (ENV@FeS) is designed to reverse adenosine immunosuppressive function. The nanovesicle is constructed through the serial extrusion of erythrocytes abundant with ADA, coupled with the synthesis of FeS complex in situ using Fe2+ in erythrocytes via H2S gas introduction. Notably, the bioactive nanovesicles not only promote tumor targeting and induce immunogenic cell death by the FeS‐induced photothermal effect, but also hinder the adenosine pathway by metabolizing adenosine into immunopotentiator inosine, further boosting antitumor immunity. In vivo, ENV@FeS efficiently increases the infiltration of cytotoxic T lymphocytes and M1 macrophages while reducing the production of regulatory T cells and myeloid‐derived suppressor cells, resulting in significant inhibition of tumor growth. Together, the biomimetic nanovesicle‐mediated adenosine metabolic regulation, in synergy with photothermal therapy, leads to a marked improvement in the immunogenic TME and enhances the therapeutic efficacy of photoimmunotherapy. [ABSTRACT FROM AUTHOR]
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- 2024
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16. Three-Dimensional Point Cloud Object Detection Based on Feature Fusion and Enhancement.
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Li, Yangyang, Ou, Zejun, Liu, Guangyuan, Yang, Zichen, Chen, Yanqiao, Shang, Ronghua, and Jiao, Licheng
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OBJECT recognition (Computer vision) , *POINT cloud , *OPTICAL radar , *LIDAR , *FEATURE extraction - Abstract
With the continuous emergence and development of 3D sensors in recent years, it has become increasingly convenient to collect point cloud data for 3D object detection tasks, such as the field of autonomous driving. But when using these existing methods, there are two problems that cannot be ignored: (1) The bird's eye view (BEV) is a widely used method in 3D objective detection; however, the BEV usually compresses dimensions by combined height, dimension, and channels, which makes the process of feature extraction in feature fusion more difficult. (2) Light detection and ranging (LiDAR) has a much larger effective scanning depth, which causes the sector to become sparse in deep space and the uneven distribution of point cloud data. This results in few features in the distribution of neighboring points around the key points of interest. The following is the solution proposed in this paper: (1) This paper proposes multi-scale feature fusion composed of feature maps at different levels made of Deep Layer Aggregation (DLA) and a feature fusion module for the BEV. (2) A point completion network is used to improve the prediction results by completing the feature points inside the candidate boxes in the second stage, thereby strengthening their position features. Supervised contrastive learning is applied to enhance the segmentation results, improving the discrimination capability between the foreground and background. Experiments show these new additions can achieve improvements of 2.7%, 2.4%, and 2.5%, respectively, on KITTI easy, moderate, and hard tasks. Further ablation experiments show that each addition has promising improvement over the baseline. [ABSTRACT FROM AUTHOR]
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- 2024
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17. Sensitive detection of trilobatin in tea beverages based on hydroxy-functionalized Ag@COF SERS substrate.
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Guan, Weinan, Chen, Guoqing, Yang, Zichen, Yang, Taiqun, Ma, Chaoqun, Li, Lei, Gao, Hui, Zhu, Chun, Cai, Zichen, Zhou, Yan, Zhang, Wei, and Li, Xin
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HIGH performance liquid chromatography , *SWEETENERS , *HYPERGEOMETRIC series , *SILVER nanoparticles , *NATURAL sweeteners , *TEA , *SERS spectroscopy - Abstract
As a dihydrochalcone natural sweetener extracted from Lithocarpus litseifolius , trilobatin is an emerging functional sweetener in the international arena in recent years and is gaining attention in the food industry. The detection of trilobatin has also gradually received the attention of researchers, however, the detection means for trilobatin still remain in the traditional high performance liquid chromatography (HPLC) and other traditional methods, which are costly and have a large detection range. In this work, a method based on the principle of surface-enhanced Raman (SERS) using a composite substrate of silver nanoparticles (Ag NPs) and covalent organic frameworks (COFs) materials is proposed for the detection of trilobatin in tea beverages. After Gaussian simulation and a series of spectral analysis methods for validation, the functionalized SERS substrates contain abundant hydroxyl groups on the surface, which can be combined with trilobatin through hydrogen bonding and greatly enhance the Raman signal of trilobatin. The specific detection of trilobatin in tea beverages has been realized and the problem of weak SERS signal of trilobatin in liquid environment has been solved. The limit of detection (LOD) of trilobatin in tea beverage was 2.8 nM, and the correlation coefficient (R2) was 0.995. The recoveries were in the range of 100.6∼106.0% with the RSD of 1.756∼4.921%. In conclusion, the experimental method is highly sensitive and specific, and can realize the nondestructive detection of trilobatin in samples with high practical value. [Display omitted] • First SERS-based method for the detection of trilobatin in beverages using Ag@COF substrates. • This method can be applied in the detection of real drink samples without pretreatment procedures. • The detection time of the substrate to the sample is short and the recovery rate is high. [ABSTRACT FROM AUTHOR]
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- 2024
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18. Highly efficient Cr (VI) removal from electroplating wastewater by regenerable copper sulfides: Mechanism and magical induction effect for Cr resource recovery.
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Ma, Chen, Liu, Mengle, Yang, Zichen, Zheng, Qianxian, Mei, Jian, and Yang, Shijian
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WASTE recycling , *COPPER sulfide , *ELECTROPLATING , *SEWAGE , *SULFIDES , *COPPER - Abstract
The current sorbents used to remove Cr (VI) from electroplating wastewater are faced with some challenges including the difficulty in separating, regenerating, and safely disposing of adsorbed Cr species. To address these challenges, CuS x /TiO 2 was developed to recover Cr (VI) from electroplating wastewater. CuS x /TiO 2 had superior performance in removing Cr (VI), with the rate and capacity of approximately 9.36 mg g−1 h−1 and 68.8 mg g−1 at initial pH 4.0, respectively. Additionally, Cu2+ released from CuS x /TiO 2 during Cr (VI) removal would come back to its external surface as the Cu(OH) 2 precipitate at initial pH 4.0, which helped to prevent the generation of secondary pollution. The Cu(OH) 2 precipitate would be decomposed into CuO x after calcination, which would then be transformed back into CuS x by re-sulfuration for regeneration. Hence, CuS x showed a magical induction effect on Cr (VI) recovery, and Cr (VI) from electroplating wastewater might be gradually enriched as Cr 2 O 3 in the sandwich between CuS x and TiO 2 through multiple regenerations and removals, which could be considered as a chromium ore resource for industrial applications when the amount of enriched Cr 2 O 3 reached more than 30 wt%. Overall, CuS x /TiO 2 showed great potential as a promising sorbent for Cr (VI) removal from electroplating wastewater. [Display omitted] • CuS x exhibits superior performance in removing Cr (VI), which outperforms common FeS x. • CuS x /TiO 2 can be recycled for Cr (VI) removal after regeneration. • CuS x shows a magical induction effect on Cr (VI) recovery. • CuS x /TiO 2 is a promising sorbent for Cr (VI) removal from electroplating wastewater. [ABSTRACT FROM AUTHOR]
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- 2023
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19. SERS Substrate Based on Cysteamine-Modified Silver Nanoparticles for Rapid Detection of Amaranth Red.
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Zhang, Wei, Chen, Guoqing, Yang, Taiqun, Ma, Chaoqun, Gao, Hui, Li, Lei, Xiong, Yi, Gu, Jiao, Zhu, Chun, Yang, Zichen, Guan, Weinan, Zhou, Yan, Li, Xin, and Cai, Zicheng
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CARBONATED beverages , *AMARANTHS , *SERS spectroscopy , *RAMAN spectroscopy , *DRINKING water - Abstract
Amaranth red is usually used as a food colorant in carbonated drinks, but long-term excess consumption of amaranth red in carbonated drinks may lead to the loss of zinc in the human body, thus causing kidney dysfunction. In this study, we developed a simple method to combine cysteamine (Cys) and silver nanoparticles (AgNPs), the surface of AgNPs was modified with Cys at room temperature, and then the amino-functionalized SERS substrate was obtained, which was applied to the determination of amaranth red in carbonated drinks. The characteristic peak in Raman spectra of amaranth red showed obvious SERS enhancement at 1570 cm−1, whose intensity had a good linear relationship with the concentration of amaranth red in carbonated drinks. The limits of detection (LOD) in water and carbonated drinks were calculated to be 1.49 μg/L and 4.13 μg/L, and the adjusted correlation coefficients (R2) were 0.992 and 0.990, respectively. In addition, the average recovery rate of amaranth red in carbonated drinks was 95.11–105.48%, and the relative standard deviation (RSD) was 4.37–8.09%. This work provides a simple and fast method for detecting amaranth red in carbonated drinks. [ABSTRACT FROM AUTHOR]
- Published
- 2023
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20. Characterization and genome sequencing of a novel T7-like lytic phage, kpssk3, infecting carbapenem-resistant Klebsiella pneumoniae.
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Shi, Yunlong, Chen, Yu, Yang, Zichen, Zhang, Yulong, You, Bo, Liu, Xinzhu, Chen, Ping, Liu, Meixi, Zhang, Cheng, Luo, Xiaoqiang, Chen, Yajie, Yuan, Zhiqiang, Chen, Jing, Gong, Yali, and Peng, Yizhi
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KLEBSIELLA pneumoniae , *BACTERIOPHAGES , *NUCLEOTIDE sequencing , *DRUG resistance in bacteria , *COMPARATIVE genomics , *BIODIVERSITY , *TRANSMISSION electron microscopy - Abstract
Carbapenem-resistant Klebsiella pneumoniae (CRKP) has spread globally and emerged as an urgent public health threat. Bacteriophages are considered an effective weapon against multidrug-resistant pathogens. In this study, we report a novel lytic phage, kpssk3, which is able to lyse CRKP and degrade exopolysaccharide (EPS). The morphological characteristics of kpssk3 observed by transmission electron microscopy, including a polyhedral head and a short tail, indicate that it belongs to the family Podoviridae. A one-step growth curve revealed that kpssk3 has a latent period of 10 min and a burst size of 200 plaque-forming units (pfu) per cell. kpssk3 was able to lyse 25 out of 27 (92.59%) clinically isolated CRKP strains, and it also exhibited high stability to changes in temperature and pH. kpssk3 has a linear dsDNA genome of 40,539 bp with 52.80% G+C content and 42 putative open reading frames (ORFs). No antibiotic resistance genes, virulence factors, or integrases were identified in the genome. Based on bioinformatic analysis, the tail fiber protein of phage kpssk3 was speculated to possess depolymerase activity towards EPS. By comparative genomics and phylogenetic analysis, it was determined that kpssk3 is a new T7-like virus and belongs to the subfamily Autographivirinae. The characterization and genomic analysis of kpssk3 will promote our understanding of phage biology and diversity and provide a potential strategy for controlling CRKP infection. [ABSTRACT FROM AUTHOR]
- Published
- 2020
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21. Evaluating rainstorm hazard prevention and mitigation capability in mountainous ecological scenic areas: A case study of the Qinling Mountains, China.
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Wang, Xiaofeng, Zhao, Cen, Yang, Zichen, Zhao, Xinxin, Xing, Tenghui, and Wang, Yanze
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HAZARD mitigation , *RAINSTORMS , *FOREST reserves , *MOUNTAIN forests , *SUSTAINABLE development - Abstract
Mountainous areas have become tourism hotspots in recent years, at the same time, some tourism safety issues have been revealed. To study rainstorm hazard prevention and mitigation capabilities, four representative scenic areas in the Qinling Mountains of China were selected as research foci for this study. The similar weight method and the unascertained measure model were used to establish an evaluation index, and the weights of indices at all levels were determined. Rainstorm hazard prevention and mitigation capabilities in the four scenic areas and on defferent slopes were then evaluated quantitatively. The results found that : according to the rainstorm hazard prevention and mitigation capabilities, the rankings of these scenic areas from high to low were Taibai Mountain National Forest Park, Cuihua Mountain National Geopark, Huayang Scenic Area, and Jinsixia National Forest Park. The rainstorm hazard prevention and mitigation capability on the north of the Qinling Mountains were higher than on the south slope, and the difference was relatively large. Rainstorm hazard prevention and mitigation capabilities on the eastern and western Qinling Mountains were more similar. These conclusions could provide a reference for regional rainstorm hazard prevention and mitigation measures, as well as sustainable development. [ABSTRACT FROM AUTHOR]
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- 2020
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22. Boric acid-functionalized silver nanoparticles as SERS substrate for sensitive and rapid detection of fructose in artificial urine.
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Shen, Jialu, Chen, Guoqing, Yang, Zichen, Wu, Yamin, Ma, Chaoqun, Li, Lei, Yang, Taiqun, Gu, Jiao, Gao, Hui, and Zhu, Chun
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RAMAN scattering , *FRUCTOSE , *SERS spectroscopy , *URINE - Abstract
[Display omitted] • The AgNPs-4MPBA composite structure was first designed as SERS substrate for detection of fructose in urine. • This method achieve the LOD of fructose to be 0.535 µmol/L in urine. • This method realizes rapid fructose detection in less than 10 min. The accurate detection of fructose in human urine can help prevent and screen for diseases such as fructokinase deficiency and hereditary fructose intolerance. Surface-enhanced Raman spectroscopy (SERS) is an analytical technique with selectivity and high sensitivity, which has been widely applied to the detection of targets with complex backgrounds. In this work, 4-mercaptophenylboronic acid (4-MPBA) was modified on the surface of silver nanoparticles (AgNPs) under mild conditions to obtain a boronic acid-functionalized SERS substrate for the detection of fructose in artificial urine. The detection mechanism was based on the deboronization reaction of 4-MPBA on the surface of AgNPs, which was induced by fructose, and the Raman signal of the generated thiophenol (TP) molecules was significantly enhanced by the silver nanoparticles, with a linear increase in SERS peak intensity at 1570 cm−1. We achieved the detection limits of 0.084 µmol/L in water and 0.535 µmol/L in urine by this method. The relative standard deviation (RSD) in the recovery experiments of urine ranged from 1.01 % to 2.22 %, and the whole detection time was less than 10 min, which indicated that this method is highly reliable for fructose detection and has a good prospect in bioassay and clinical medicine. [ABSTRACT FROM AUTHOR]
- Published
- 2023
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23. Pancreatic lipase inhibitory effects of peptides derived from sesame proteins: In silico and in vitro analyses.
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Wang, Xinyi, Ai, Xin, Zhu, Zehui, Zhang, Mingxin, Pan, Fei, Yang, Zichen, Wang, Ou, Zhao, Liang, and Zhao, Lei
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PEPTIDES , *LIPASES , *DIGESTIVE enzymes , *SESAME , *PROTEINS , *PEPSIN , *PANCREATIC enzymes - Abstract
Pancreatic lipase (PL) is the main digestive enzyme that is responsible for breaking triglycerides into smaller components for absorption. Inhibition of PL can effectively reduce triglyceride absorption, helping to prevent the development of obesity. The objective of this study was to investigate the PL inhibitory activity of peptides derived from sesame (Sesamum indicum L.) in silico and in vitro. In silico proteolysis of sesame proteins with pepsin, trypsin and chymotrypsin was performed with ExPASy PeptideCutter. Six peptides (TF, EW, QWM, NIF, AGY and PIF) were screened out by PeptideRanker, SwissADME and AutoDock. Molecular docking analysis showed that these six peptides could interact directly with Phe77, His151, Ser152, Phe215 and His263 at the key sites of PL. The six peptides were further synthesized to verify their PL-inhibitory effects in vitro , and TF, EW, QWM, NIF and AGY exhibited inhibitory activity on PL with IC 50 values of 751 ± 75, 907 ± 91, 986 ± 170, 1044 ± 179 and 1183 ± 179 μM, respectively. Inhibitory kinetics indicated that TF, QWM and NIF were mixed-type inhibitors of PL, while EW and AGY were uncompetitive inhibitors. Our results suggest that peptides from sesame could potentially inhibit the activity of PL. [Display omitted] • 11S globulin and 2S albumin from sesame seeds was selected for in silico digestion. • Five pancreatic lipase (PL) inhibitory peptides were screened in silico and in vitro. • The IC 50 values of five peptides were smaller than or close to that of orlistat. • Peptides could interact with active sites of PL via H-bonds and hydrophobic forces. • TF, QWM and NIF were mixed-type inhibitors, while EW and AGY were uncompetitive ones. [ABSTRACT FROM AUTHOR]
- Published
- 2022
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24. Fine‐Tuning Single‐Source White‐Light Emission from All‐Inorganic Corrugated 2D Antimony‐Halide Perovskite.
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Xu, Fei, Wang, Xiang, Li, Yue, Jiang, Beng, Dong, Zuoru, Yang, Zichen, Kang, Jiaxing, Shu, Xin, Jiang, Zuimin, Hong, Feng, Xu, Run, Ma, Zhongquan, Chen, Teng, Xu, Zhan, and Xu, Haitao
- Subjects
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RARE earth metals , *LUMINESCENCE quenching , *SAMARIUM , *PEROVSKITE , *ELECTRON-phonon interactions , *ANTIMONY , *COLOR temperature - Abstract
Corrugated 2D antimony‐halide perovskites such as Cs3Sb2Cl9 (CSC) are promising candidates for single‐source white‐light emission due to their ultra‐broadband spectra. However, CSC has a serious luminescence quenching phenomenon due to inadequate confinement of excitons. By the homovalent substitution of trivalent antimony cation Sb3+ by a small amount of trivalent rare earth (RE) cations RE3+, the photoluminescence intensities from high‐quality Cs3(Sb1−xREx)2Cl9 (CSRC) (RE = Ce, Sm, Nd, Y, Er, etc.) films at room temperature (RT) are over two orders of magnitude higher than that of CSC film. Especially, the photoluminescence quantum yield (PLQY) for the Cs3(Sb0.995Er0.005)2Cl9 film is 9.5% at RT, which is much higher than A3B2X9 perovskites previously reported for single‐source white‐light lighting. Furthermore, the Cs3(Sb0.995Er0.005)2Cl9 film exhibits an ultra‐broadband emission with the full width at half maximum reaching 554 meV at RT, resulting in a "warm" white‐light with the CIE coordinate (0.33, 0.46) and the correlated color temperature of 5450 K. The PLQY enhancement can be considered as the fact that a high activation energy by bandgap widening effect and Type‐I‐like "straddling" band alignment between Cs3Sb2Cl9 and Cs3Er2Cl9 lead to reducing nonradiative losses and increasing radiative recombination channels. Meanwhile, the spectral broadening can be considered to be attributed to strong effect of electron–phonon interaction. [ABSTRACT FROM AUTHOR]
- Published
- 2022
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25. Exposure of pregnant women to neonicotinoids in Wenzhou City, East China: A biomonitoring study.
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Huang, Min, Wang, Yuanping, Wang, Yi, Lin, Guankai, Wen, Xiaoting, Xu, Xiaoyang, Hong, Sumiao, Chen, Yuanyuan, Lin, Haiping, Yang, Zichen, Zhao, Ke, Liu, Jiaqi, Wang, Jiwei, Wang, Hexing, Wang, Na, Chen, Yue, and Jiang, Qingwu
- Subjects
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NEONICOTINOIDS , *LIQUID chromatography-mass spectrometry , *DRIED milk , *PREGNANT women , *SCREEN time , *INCOME - Abstract
[Display omitted] • At least one neonicotinoid or metabolite was detected in 93.5% of urine samples. • DM-ACE, CLO, THM, and DM-CLO were dominant neonicotinoids and metabolites. • Certain basic characteristics of pregnant women influenced neonicotinoid exposure. • Multiple food categories were identified as potential exposure sources. • A low health risk was found based on current safety thresholds. China produces and consumes a large amount of neonicotinoids. A non-negligible exposure to neonicotinoids might occur for Chinese pregnant women, but relevant data remain limited. To investigate the exposure to neonicotinoids by urinary biomonitoring in pregnant women from Wenzhou City, East China. We selected 432 pregnant women in Wenzhou City in 2022. A total of eight parent neonicotinoids and four metabolites were determined in single spot urine by liquid chromatography coupled to mass spectrometry. Basic characteristics, physical activity, pre-pregnant body mass index, and intake of drinking water and food were investigated by the questionnaire. Health risk was assessed by hazard quotient (HQ) and hazard index (HI) based on human safety thresholds derived from different health endpoints. Neonicotinoids and their metabolites in urine had a detection frequency between 0 % and 80.1 %. At least one neonicotinoid or metabolite was detected in 93.5 % of urine samples. Except for clothianidin (51.2 %) and N-desmethyl-acetamiprid (80.1 %), the detection frequencies of other neonicotinoids and metabolites ranged from 0 % to 43.8 %. The summed concentrations of all neonicotinoids and their metabolites ranged from < LOD to 222.83 μg/g creatinine with the median concentration of 2.58 μg/g creatinine. Maternal age, educational level, occupation, household income, screen time, and pre-pregnant body mass index were associated with detection frequencies or concentrations of neonicotinoids and their metabolites. Pregnant women with higher consumption frequencies of wheat, fresh vegetable, shellfish, fresh milk, and powdered milk had higher detection frequencies of neonicotinoids and their metabolites. Both HQ and HI were less than one. Overall, pregnant women in Wenzhou City showed a notable frequency of exposure to at least one neonicotinoid, although the exposure frequency for each specific neonicotinoid was generally low. Several food items derived from plants and animals were potential exposure sources. A low health risk was found based on current safety thresholds. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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26. SERS substrate based on COF@Ag for detecting amoxicillin in honey and lake water.
- Author
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Chen, Kun, Ma, Chaoqun, Chen, Guoqing, Yang, Taiqun, Gao, Hui, Li, Lei, Yang, Zichen, Cao, Jun, Zheng, Chenkai, and Ma, Longyao
- Subjects
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HONEY , *SERS spectroscopy , *AMOXICILLIN , *DETECTION limit , *FRONTIER orbitals - Abstract
[Display omitted] • In this study, a stable, uniform, and sensitive SERS substrate was successfully synthesized by combining COFs and AgNPs. • We conducted a detailed analysis of the specific role of COFs in the substrate through their characterization and DFT simulation. • The detection limits achieved in amoxicillin aqueous solution, lake water, and honey were found to be satisfactory. Specifically, the detection limits were 0.279 μg/L in the aqueous solution, 8.246 μg/L in lake water, and 2.47 ng/g in honey. This study presents the design of a Surface-enhanced Raman scattering (SERS) substrate, COF@Ag, for the sensitive detection of Amoxicillin (AMX) in lake water and honey. Furthermore, the study investigates the role of covalent organic frameworks (COFs) in SERS detection. The characterization results demonstrate the capability of COFs to efficiently enrich Ag nanoparticles (AgNPs), resulting in a more concentrated distribution of hotspots and an enhanced electromagnetic field on the substrate. By employing density functional theory (DFT) simulation, the frontier electronic orbitals of COFs and AMX were analyzed, and the chemical bonds and weak interactions in the system were examined using the Interaction Region Indicator (IRI) method to propose potential enhancement mechanisms. In aqueous solutions, the linear range is 1 μg/L-30 μg/L, with a limit of detection (LOD) 0.279 μg/L. In lake water, the linear range span from 100 μg/L to 500 μg/L, with a detection limit of 8.244 μg/L. For honey, the linear range extend from 20 ng/g to 100 ng/g, with a detection limit of 2.917 ng/g. This method holds key significance in facilitating the rapid detection of amoxicillin and advancing the application of COFs in SERS. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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27. Arginine-assembly as NO nano-donor prevents the negative feedback of macrophage repolarization by mitochondrial dysfunction for cancer immunotherapy.
- Author
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Zheng, Xiao, Liu, Ying, Liu, Yiqiong, Zang, Jie, Wang, Kun, Yang, Zichen, Chen, Nana, Sun, Jiuyuan, Huang, Li, Li, Yan, Xue, Liangyi, Zhi, Hui, Zhang, Xiaoyou, Yu, Min, Chen, Shiyu, Dong, Haiqing, and Li, Yongyong
- Subjects
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TOLL-like receptor agonists , *MACROPHAGES , *TOLL-like receptors , *NITRIC-oxide synthases , *IMMUNOTHERAPY , *IMMUNE response , *MITOCHONDRIA - Abstract
Repolarizing the tumor-associated macrophages (TAMs) towards the antitumoral M1-like phenotype has been a promising approach for cancer immunotherapy. However, the anti-cancer immune response is severely limited mainly by the repolarized M1-like macrophages belatedly returning to the M2-like phenotype (i.e., negative feedback). Inspired by nitric oxide (NO) effectively preventing repolarization of inflammatory macrophages in inflammatory diseases, herein, we develop an arginine assembly, as NO nano-donor for NO generation to prevent the negative feedback of the macrophage repolarization. The strategy is to first apply reversible tagging of hydrophobic terephthalaldehyde to create an arginine nano-assembly, and then load a toll-like receptor 7/8 agonist resiquimod (R848) (R848@Arg). Through this strategy, a high loading efficiency of 40 % for the arginine and repolarization characteristics for TAMs can be achieved. Upon the macrophage repolarization by R848, NO can be intracellularly generated from the released arginine by the upregulated inducible nitric oxide synthase. Mechanistically, NO effectively prevented the negative feedback of the repolarized macrophage by mitochondrial dysfunction via blocking oxidative phosphorylation. Notably, R848@Arg significantly increased the tumor inhibition ratio by 3.13-fold as compared to the free R848 by maintaining the M1-like phenotype infiltrating into tumor. The Arg-assembly as NO nano-donor provides a promising method for effective repolarization of macrophages. [Display omitted] [ABSTRACT FROM AUTHOR]
- Published
- 2024
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28. Source and health risk of urinary neonicotinoids in Tibetan pregnant women.
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Wang, Yuanping, Gesang, Yangzong, Wang, Yi, Yang, Zichen, Zhao, Ke, Liu, Jiaqi, Li, Chunxia, Ouzhu, Luobu, Wang, Hexing, Chen, Yue, and Jiang, Qingwu
- Subjects
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PREGNANT women , *NEONICOTINOIDS , *CARBONATED beverages , *INFLUENCE of altitude , *TIBETANS , *INCOME - Abstract
High altitude could influence the level of exposure to neonicotinoids, but relevant data remain limited for people living in Tibet. We investigated 476 Tibetan pregnant women from Lhasa of Tibet, China in 2021 and measured eight neonicotinoids and four metabolites in urine. Food consumption was investigated by a food frequency questionnaire. Health risk was assessed by using hazard quotient (HQ) and hazard index (HI) based on acceptable daily dose or chronic reference dose. Neonicotinoids and metabolites were overall detected in 56.5% of urine samples with a median concentration being 0.73 μg g−1 creatinine. Four neonicotinoids or metabolites were detected in more than 10% of urine samples, including N-desmethyl-acetamiprid (47.5%), clothianidin (15.5%), thiamethoxam (16.0%), and imidacloprid (10.5%). Annual household income, family smoking, and pre-pregnancy body mass index were associated with the detection frequencies of neonicotinoids. Pregnant women with a higher consumption frequency of wheat, rice, fresh vegetable, fresh fruit, beef and mutton, fresh milk, yoghourt, candy and chocolate, or carbonated drinks had a higher detection frequency of neonicotinoids. Both HQ and HI were less than one. There was an evident exposure to neonicotinoids in Tibetan pregnant women with both plant- and animal-derived food items as exposure sources, but a low health risk was found based on current safety thresholds. [Display omitted] • Neonicotinoids and metabolites were overall detected in 56.5% of urine samples. • DM-ACE, CLO, THM, and IMI were dominant neonicotinoids and metabolites. • Certain basic characteristics of pregnant women influenced neonicotinoid exposure. • Both plant- and animal-derived foods were identified as potential exposure sources. • A low health risk for pregnant women was found based on current safety thresholds. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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29. Highly Photoluminescent Carbon Dots with pH-Dependent Switchable Fluorescence and Sensitivity to Tetracycline.
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Wang, Chengwei, Li, Lei, Wu, Yamin, Gu, Jiao, Ma, Chaoqun, Zhu, Chun, Gao, Hui, Zhang, Ye, Shang, Yunpeng, Yang, Zichen, and Chen, Guoqing
- Subjects
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TETRACYCLINE , *TETRACYCLINES , *FLUORESCENCE , *LINEAR equations , *PH effect , *CARBON - Abstract
In this paper, multifunctional nitrogen-doped carbon dots (N-CDs) were synthesized from 3,5-diaminobenzonitrile by a simple one-step hydrothermal method. The N-CDs have a high quantum yield of 67.0% in ethanol with great water solubility, temperature stability, light stability and resistance to ion interference. Experiments showed that pH has an effect on the fluorescence intensity and emission wavelength of N-CDs. Especially, the switchable fluorescence of N-CDs caused by changes of pH value could be distinguished to the naked eye. Additionally, the multifunctional N-CDs also showed a selective response to tetracycline. We studied the influence of tetracycline on the luminescence intensity of N-CDs in the concentration range of 0–1000 μ g/L. A linear equation was established in the range of 10–80 μ g/L with a limit of detection (LOD) of 3.5 μ g/L. Based on the above excellent characteristics, N-CDs are expected to be applied in the field of sensing. In this study, nitrogen-doped carbon dots (N-CDs) were synthesized from 3,5-diaminobenzonitrile by a simple one-step hydrothermal method. The N-CDs have good water solubility and high quantum yield. More importantly, the diverse and sensitive responses of N-CDs to pH and tetracycline indicate that N-CDs can be used as good probe. [ABSTRACT FROM AUTHOR]
- Published
- 2021
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30. Polyethyleneimine-functionalized Silver Nanoparticles as SERS Substrates for the Detection of Chrysoidine.
- Author
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Zhang, Wei, Chen, Guoqing, Ma, Chaoqun, Gao, Hui, Yang, Taiqun, Li, Lei, Zhu, Chun, Yang, Zichen, Guan, Weinan, Li, Xin, and Zhou, Yan
- Abstract
Chrysoidine, an industrial dye, is a banned chemical for use as a food additive. Studies have shown that excessive ingestion, inhalation and dermal contact with the substance can cause acute and chronic toxicological damage. Surface enhanced Raman spectroscopy (SERS) is a spectroscopic detection technique with high selectivity and sensitivity. In this study, a mixture of silver nanoparticles (AgNPs) and polyethyleneimine (PEI) was used as the SERS substrate at room temperature for the rapid and sensitive detection of Chrysoidine in mirinda soft drink, and PEI could attract Chrysoidine to the hot spot region of the AgNPs and enhance its Raman signal. The characteristic peak of the SERS spectrum of Chrysoidine showed obvious SERS enhancement at 1180 cm− 1, and there was a good linear relationship between the SERS intensity and the concentration of Chrysoidine. The limits of detection (LOD) in both water and mirinda soft drink were determined to be 1.32 µg/L and 5.11 µg/L, respectively. In addition, the average recoveries ranged from 95.65 to 102.08% with the RSDs of 3.41-5.02%. The method can be successfully used for the rapid and sensitive detection of Chrysoidine in mirinda soft drink, which provides a new idea for the detection of Chrysoidine in other different samples. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
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31. Antimicrobial resistance and virulence genes profiling of methicillin-resistant Staphylococcus aureus isolates in a burn center: A 5-year study.
- Author
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Jiang, Bei, Yin, Supeng, You, Bo, Gong, Yali, Huang, Guangtao, Yang, Zichen, Zhang, Yulong, Chen, Yu, Chen, Jing, Yuan, Zhiqiang, Hu, Xiaomei, and Peng, Yizhi
- Subjects
- *
ANTI-infective agents , *DRUG resistance in bacteria , *VIRULENCE of bacteria , *METHICILLIN-resistant staphylococcus aureus , *MICROBIAL sensitivity tests - Abstract
Methicillin-resistant S. aureus (MRSA) has attracted more and more attention in recent years, especially in burn medical centers. Here we conducted a 5-year period study to evaluate the MRSA infection in our burn center. The staphylococcal chromosomal cassette mec ( SCCmec ) typing, antimicrobials susceptibility and virulence profiles were also performed among the MRSA isolates. Of the 259 S. aureus isolates, 239 (92.28%) isolates were identified as MRSA. A decreased trend of MRSA isolation rate over time was found ( P = 0.0063). Majority of MRSA isolates in our center belonged to SCCmec type III (230/239, 96.23%). Antimicrobials susceptibility tests of the MRSA isolates revealed significantly decreased resistance to clindamycin ( P = 0.0183), and increased resistance to chloramphenicol ( P = 0.0020) and minocycline ( P < 0.0001) over time. Trimethoprim/sulfamethoxazole, clindamycin, vancomycin, teicoplanin and linezolid were suggested to be good choice for MRSA infection in our center. Virulence factors profiling showed that most of MRSA isolates in our center carried the virulence factor pattern of cna - clfA - clfB - eno - fib - icaA - icaD - sea - psmα - lukED - hlg - hlgv - hla - hld (214/239, 89.54%). In conclusion, our study suggests that MRSA infection is serious in our burn center, but presented decreased trend over time. Most of MRSA isolates in our center presented the same virulence factor profile. More attention should be attached to nosocomial infection in burn medical center. Antimicrobials susceptibility changing over time was observed. Antimicrobials susceptibility monitoring is necessary and helps to select appropriate drugs against MRSA infections. [ABSTRACT FROM AUTHOR]
- Published
- 2018
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32. Phage Abp1 Rescues Human Cells and Mice from Infection by Pan-Drug Resistant Acinetobacter Baumannii.
- Author
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Yin, Supeng, Huang, Guangtao, Zhang, Yulong, Jiang, Bei, Yang, Zichen, Dong, Zhiwei, You, Bo, Yuan, Zhiqiang, Hu, Fuquan, Zhao, Yan, and Peng, Yizhi
- Subjects
- *
ACINETOBACTER baumannii , *DRUG resistance in bacteria , *BACTERIOPHAGES , *DRUG efficacy , *LABORATORY mice ,INFECTION treatment - Abstract
Background/Aims: As an "ESKAPE" pathogen, Acinetobacter baumannii is one of the leading causes of drug-resistant infections in humans. Phage therapy may be a useful strategy in treating infections caused by drug-resistant A. baumannii. Among 21 phage strains that were isolated and described earlier, we investigated the therapeutic efficacy of Abp1 because of its relatively wide host range. Methods: Phage stability assays were used to evaluate thermal and pH stability of Abp1. Abp1 was co-cultured with A. baumannii (AB1) over a range of multiplicities of infection to determine its bactericidal efficacy. HeLa or THP-1 cells were used in the cytotoxicity and protection assays. Finally, the therapeutic effects of Abp1 on local and systemic A. baumannii infection in mice were determined. Results: We found that Abp1 exhibits high thermal and pH stability and has a low frequency of lysogeny. Bacteriophage resistance also occurs at a very low frequency (3.51±0.46×10-8), and Abp1 can lyse almost all host cells at a MOI as low as 0.1. Abp1 has no detectable cytotoxicity to HeLa or THP-1 cells as determined by LDH release assay. Abp1 can rescue HeLa cells from A. baumannii infection, even if introduced 2 hours post infection. In both local and systemic A. baumannii infection mouse models, Abp1 treatment exhibits good therapeutic effects. Conclusion: Abp1 is an excellent candidate for phage therapy against drug-resistant A. baumannii infections. [ABSTRACT FROM AUTHOR]
- Published
- 2017
- Full Text
- View/download PDF
33. Astragaloside-IV Alleviates Heat-Induced Inflammation by Inhibiting Endoplasmic Reticulum Stress and Autophagy.
- Author
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Dong, Zhiwei, Zhou, Jian, Zhang, Ying, Chen, Yajie, Yang, Zichen, Huang, Guangtao, Chen, Yu, Yuan, Zhiqiang, Peng, Yizhi, and Cao, Tongtong
- Subjects
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INFLAMMATION treatment , *ASTRAGALUS membranaceus , *PHYSIOLOGICAL effects of heat , *ENDOPLASMIC reticulum , *AUTOPHAGY , *INFLAMMATION , *POLYMERASE chain reaction , *PHYSIOLOGY - Abstract
Background: Thermal injury is the main cause of pulmonary disease in stroke after burn and can be life threatening. Heat-induced inflammation is an important factor that triggers a series ofinduces pathological changes. However, this mechanism underlying heat-induced inflammation in thermal inhalation injury remains unclear. Studies have revealed that astragaloside-IV (AS-IV), a natural compound extracted from Astragalus membranaceus, has protective effects in inflammatory diseases. Here, we investigated whether the protective effects of AS-IV occur because of the suppression of heat- induced endoplasmic reticulum (ER) stress and excessive autophagy. Methods: AS-IV was administered to Wistar rats after thermal inhalation injury and 16HBE140-cells were treated with AS-IV. TNF-α, IL-6, and IL-8 levels were determined by ELISA and real-time PCR. ER stress and autophagy were determined by western blot. Autophagic flux was measured by recording the fluorescence emission of the fusion protein mRFP-GFP-LC3 by dynamic live-cell imaging. Results: AS-IV had protective effects against heat-induced reactive oxygen species production and attenuated ER stress. AS-IV alleviated heat- induced excessive autophagy in vitro and in vivo. Excessive autophagy was attenuated by the PERK inhibitor GSK2656157 and eIF2α siRNA, suggesting that heat stress-induced autophagy can activate the PERK-eIF2α pathway. Beclin 1 and Atg5 siRNAs inhibited the upregulation of the inflammatory cytokines TNF-α, IL-6, and IL-8 after heat exposure. Conclusions: Thus, AS-IV may attenuate inflammatory responses by disrupting the crosstalk between autophagy and the PERK-eIF2α pathway and may be an ideal agent for treating inflammatory pulmonary diseases. [ABSTRACT FROM AUTHOR]
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- 2017
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34. Concurrent CCR7 Overexpression and RelB Knockdown in Immature Dendritic Cells Induces Immune Tolerance and Improves Skin-Graft Survival in a Murine Model.
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Dong, Zhiwei, Chen, Yajie, Peng, Yuan, Wang, Fan, Yang, Zichen, Huang, Guangtao, Chen, Yu, Yuan, Zhiqiang, Cao, Tongtong, and Peng, Yizhi
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GENETIC overexpression , *DENDRITIC cells , *IMMUNOLOGICAL tolerance , *SKIN grafting , *ANIMAL models in research , *SMALL interfering RNA , *LABORATORY mice , *PHYSIOLOGY - Abstract
Background/Aims: Skin transplantation aims to cover skin defects but often fails due to immune rejection of the transplantated tissue. Immature dendritic cells (imDCs) induce immune tolerance but have a low migration rate. After stimulation, imDCs transform into mature DCs, which activate immune rejection. Thus, inducing imDC to obtain a high migration counteracts development of immune tolerance. Methods & Results: We transfected imDCs with a recombinant adenovirus carrying the CCR7 gene (Ad-CCR7) and a small interfering RNA targeting RelB (RelB-siRNA) to concurrently overexpress CCR7 and downregulate RelB expression. Functionally, such cells showed a significantly enhanced migration rate in the chemotactic assay and decreased T-cell proliferation after lipopolysaccharide stimulation in mixed lymphocyte reactions. Cotransfected cells showed an increased ability to induce immune tolerance by upregulating T regulatory (Treg) cells and shifting the Th1/Th2 ratio. Cotransfection of Ad-CCR7 and RelB-siRNA endowed imDCs with resistance to apoptosis and cell death. CCR7 overexpression and RelB knockdown (KD) in imDCs improve skin-graft survival in a murine skin-transplantation model. Conclusion: Transfection with Ad-CCR7 and RelB KD in imDCs may be an effective approach inducing immune tolerance, thus being potentially valuable for inhibiting allograft rejection. [ABSTRACT FROM AUTHOR]
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- 2017
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35. Epidemiological characterization of Acinetobacter baumannii bloodstream isolates from a Chinese Burn Institute: A three-year study.
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Huang, Guangtao, Yin, Supeng, Xiang, Lijuan, Gong, Yali, Sun, Kedai, Luo, Xiaoqiang, Zhang, Cheng, Yang, Zichen, Deng, Liuyang, Jiang, Bei, Jin, Shouguang, Chen, Jing, and Peng, Yizhi
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BACTERIAL disease risk factors , *BURN patients , *EPIDEMIOLOGY , *ACINETOBACTER baumannii , *DRUG resistance in bacteria , *NUCLEOTIDE sequencing , *PUBLIC health , *ACINETOBACTER infections , *ANTIBIOTICS , *BACTEREMIA , *BACTERIAL proteins , *BACTERIOPHAGE typing , *BURNS & scalds , *CROSS infection , *DRUG resistance in microorganisms , *HYDROLASES , *MICROBIAL sensitivity tests , *MOLECULAR epidemiology , *POLYMERASE chain reaction , *RNA , *RETROSPECTIVE studies , *GRAM-negative aerobic bacteria , *SEQUENCE analysis , *PHARMACODYNAMICS - Abstract
Acinetobacter baumannii infection is a serious threat to burn patients. Bacteremia due to A. baumannii is becoming the most common cause of mortality following burn. However, the epidemiology of A. baumannii causing burn-related bloodstream infections has rarely been reported. We retrospectively collected 81 A. baumannii isolates from the bloodstream of burn patients over a three-year period. Antibiotic susceptibility tests, the prevalence of antibiotic-resistant genes and sequence typing (ST) were conducted to characterize these strains. Most of the isolates showed an extensive drug-resistant phenotype. The resistance frequencies to imipenem and meropenem were 94% and 91%, respectively. The blaOXA-23-like gene, AmpC, IS-AmpC, PER and SIM are the five most prevalent resistant genes, and their prevalence rates are 93% (75/81), 86% (70/81), 73% (59/81), 73% (59/81) and 52% (42/81), respectively. The 81 isolates were grouped into 10 known and 18 unknown ST types, with ST368 (38%) being the most prevalent. Except for ST457 and four new types (STn2, STn6, STn11 and STn14), the remaining 23 ST types belonged to one clonal complex 92, which is most common among clinical isolate in China. The above results indicated that ST368 isolates possessing both the blaOXA-23-like gene and ampC gene were the main culprits of the increasing nosocomial A. baumannii infection in this study. More attention should be paid to monitoring the molecular epidemiology of A. baumannii isolates from burn patients to prevent further distribution. Such information may help clinicians with therapeutic decisions and infection control in the Burns Institute. [ABSTRACT FROM AUTHOR]
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- 2016
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36. Antibiotic residues in honey in the Chinese market and human health risk assessment.
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Wang, Yuanping, Dong, Xiaolian, Han, Minghui, Yang, Zichen, Wang, Yi, Qian, Lu, Huang, Min, Luo, Baozhang, Wang, Hexing, Chen, Yue, and Jiang, Qingwu
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HONEY , *ANTIBIOTIC residues , *HEALTH risk assessment , *ANTIBIOTICS , *ANTIBIOTIC overuse , *NORFLOXACIN - Abstract
China is a major country of producing, exporting and consuming honey. However, the data about antibiotic residues in honey and their health risk remain limited. This study collected 94 honey samples circulating in the Chinese market, determined 20 common antibiotics from four categories in relation to the characteristics of honey samples, and assessed the potential human health risk. Antibiotics were overall found in 84.0 % of honey with a median concentration of 0.09 ng/g. Two or more antibiotics were simultaneously found in 56.2 % of honey. Quinolones were found in 69.1 % of honey, followed by sulfonamides (44.7 %), tetracyclines (26.6 %), and phenicols (1.1 %). Honey produced in China and honey with a lower price had higher detection frequencies and/or concentrations of quinolones, sulfonamides, or sum of all antibiotics. A lower detection frequency was seen for sum of all antibiotics in honey from commercial than non-commercial crops. The maximum HIs based on microbiological and toxicological effects were 1.80 × 10−2 and 3.20 × 10−5 for adults, respectively and were 1.59 × 10−2 and 2.82 × 10−5 for children, respectively. These results indicated an extensive antibiotic residue in honey circulating in the Chinese market, which varied with production place, sale price, and commercial category of nectariferous plants, and a low health risk on human. [Display omitted] • Antibiotics were found in 84.0 % of honey samples collected from the Chinese market. • Norfloxacin, ofloxacin, trimethoprim, and tetracycline were most found in honey samples. • Antibiotic residues varied by production place, sale price, and commercial categories of nectariferous plants. • The health risk was low for human based on the current human safety threshold. • There might be a misuse or overuse of antibiotics in beekeeping. [ABSTRACT FROM AUTHOR]
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- 2022
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37. Fine‐Tuning Single‐Source White‐Light Emission from All‐Inorganic Corrugated 2D Antimony‐Halide Perovskite (Advanced Optical Materials 17/2022).
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Xu, Fei, Wang, Xiang, Li, Yue, Jiang, Beng, Dong, Zuoru, Yang, Zichen, Kang, Jiaxing, Shu, Xin, Jiang, Zuimin, Hong, Feng, Xu, Run, Ma, Zhongquan, Chen, Teng, Xu, Zhan, and Xu, Haitao
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OPTICAL materials , *PEROVSKITE , *LUMINESCENCE quenching , *RARE earth metals , *ELECTRON-phonon interactions - Abstract
2D perovskites, homovalent substitution, self-trapping exciton emission, white-light lighting Fine-Tuning Single-Source White-Light Emission from All-Inorganic Corrugated 2D Antimony-Halide Perovskite (Advanced Optical Materials 17/2022) Keywords: 2D perovskites; homovalent substitution; self-trapping exciton emission; white-light lighting EN 2D perovskites homovalent substitution self-trapping exciton emission white-light lighting 1 1 1 09/07/22 20220901 NES 220901 Corrugated 2D antimony-halide perovskites such as Cs SB 3 sb Sb SB 2 sb Cl SB 9 sb (CSC) are promising candidates for single-source white-light emission due to their ultra-broadband spectra. [Extracted from the article]
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- 2022
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38. TMB-AgNPs@COF based SERS probe for the rapid detection of glucose in drinks.
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Shen, Jialu, Zhu, Chun, Li, Lei, Yang, Taiqun, Wu, Yamin, Ma, Chaoqun, Gu, Jiao, Gao, Hui, Yang, Zichen, Wang, Zirui, Qiu, Xiaoqian, Zhong, Lvyuan, Hu, Anqi, Huang, Anlan, Xu, Jinzeng, Guo, Senqi, Yin, Wenzhi, and Chen, Guoqing
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GLUCOSE , *SERS spectroscopy , *GLUCOSE oxidase - Abstract
The detection of glucose in drinks (especially for sugar-free drinks) is of great practical significance. The traditional method for the detection of glucose was based on an enzymatic reaction using glucose oxidase, which takes a long time. Herein, a TMB-AgNPs@COF based SERS probe was designed for the rapid detection of glucose in drinks. The SERS probe was fabricated using silver nanoparticles loaded covalent organic frameworks (COFs) as substrate, 3,3',5,5'-Tetramethylbenzidine (TMB) was introduced as a signal molecule to solve the problem of weak SERS signal of glucose. The fabricated SERS probe is denoted as TMB-AgNPs@COF. The detection mechanism was based on the competitive binding of TMB and glucose with AgNPs@COF substrate. Glucose was more likely to bond with the substrate which was verified by Gaussian theory simulation. The SERS signal of TMB gradually decreased when glucose was introduced. The interaction between the substrate and glucose can also be demonstrated by SERS spectroscopy. By applying this method, we could achieve the detection limit of 0.096 μg/mL in drinks. The relative standard deviations were 2.63 %− 4.89 % in the recovery experiments of drinks. The whole detection time was less than 5 min and the substrate had good reproducibility. Therefore, the method was confirmed with a high potential for the detection of glucose in drinks. [Display omitted] • The TMB-AgNPs@COF was first designed as SERS probe for detection of glucose in drinks. • This method can be applied in the detection of real drink samples without pretreatment procedures. • This method realizes rapid glucose detection in less than 5 min. [ABSTRACT FROM AUTHOR]
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- 2022
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39. Sensitive determination of Norfloxacin in milk based on β-cyclodextrin functionalized silver nanoparticles SERS substrate.
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Qiu, Xiaoqian, Gu, Jiao, Yang, Taiqun, Ma, Chaoqun, Li, Lei, Wu, Yamin, Zhu, Chun, Gao, Hui, Yang, Zichen, Wang, Zirui, Li, Xiaolin, Hu, Anqi, Xu, Jinzeng, Zhong, Lvyuan, Shen, Jialu, Huang, Anlan, and Chen, Guoqing
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SURFACE enhanced Raman effect , *SERS spectroscopy , *CYCLODEXTRINS , *RAMAN scattering , *NORFLOXACIN , *SILVER nanoparticles , *FLUORESCENCE spectroscopy , *MILK - Abstract
[Display omitted] • The β-CD-AgNPs substrate can selectively combine with NFX. And the proposed method can be applied in the detection of real milk samples. • The "host–guest" interaction of NFX and β-CD-AgNPs was verified by the UV–Vis absorption spectroscopy, fluorescence spectroscopy, Zeta potential and DLS. • This developed SERS method is simple and sensitive, the LOD of NFX was 3.214 pmol/L in standard solution and 5.327 nmol/L in milk. The norfloxacin (NFX) residue in milk will increase human resistance to drugs and pose a threat to public health. In this work, a highly sensitive method for detection of NFX was developed based on surface enhanced Raman spectroscopy (SERS) using β-cyclodextrin functionalized silver nanoparticles (β-CD-AgNPs) as substrate. The unique spatial size and hydrophilicity of β-CD on the surface of AgNPs could selectively capture the target molecule (NFX) through some weak interactions, including hydrogen-bond interaction, electrostatic interaction, etc. The interactions were characterized by the UV–Vis absorption spectroscopy, fluorescence spectroscopy, Zeta potential and DLS. The Raman signal of NFX is largely enhanced when anchored by β-CD on the surface of AgNPs due to SERS effect. Through a series of experiments and analysis, the limit of detection (LOD) in standard solution and spiked milk were calculated to be 3.214 pmol/L and 5.327 nmol/L. The correlation coefficients (R2) were 0.986 and 0.984, respectively. For milk sample determination of NFX, the recovery was 101.29% to 104.00% with the relative standard deviation (RSD) from 2.986% to 9.136%. To sum up, this developed SERS strategy is sensitive and specific to detect NFX in milk, it has practical application value and prospects. [ABSTRACT FROM AUTHOR]
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- 2022
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40. A sensitive method for detecting sodium thiocyanate using AgNPs and MIL-101(Fe) combined as SERS substrate.
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Wang, Zirui, Ma, Chaoqun, Wu, Yamin, Gu, Jiao, Zhu, Chun, Li, Lei, Gao, Hui, Yang, Zichen, Li, Xiaolin, Wei, Yitao, Wang, Guoyu, Guo, Senqi, and Chen, Guoqing
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SERS spectroscopy , *METAL-organic frameworks , *SODIUM , *MILK - Abstract
Sodium thiocyanate (NaSCN) is normally used as a kind of food preservative in daily life, but using excessive NaSCN in milk would cause the low absorption of iodine in human body, and then would make the normal secretion of thyroid hormone disorder. In this study, we developed a method combines AgNPs and MIL-101(Fe) which is a kind of Metal organic frameworks materials as a kind of composite Surface Enhanced Raman Scattering (SERS) substrate and achieved the determination of NaSCN in spiked milk. The characteristic peak of NaSCN at 2110 cm−1 showed obvious SERS enhancement and has good linearity with the concentration of NaSCN in milk. Through the simple and rapid detection, the limit of detection in water and milk was calculated as 18.5 μg/L and 96.3 μg/L with the correlation coefficient of 0.991 and 0.988 respectively. This work provides a new method to detect NaSCN in milk and expands the application of SERS in food detection. [ABSTRACT FROM AUTHOR]
- Published
- 2021
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