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Perfluoroalkyl substances (PFASs) are emerging contaminants capable of harming human health, primarily via ingesting aquatic products. The current study monitored a survey of 23 PFASs in 1049 aquatic products from the coasts of the Yellow-Bohai Sea in China to comprehensively investigate the concentrations and distributions of PFASs. PFOA, PFOS, PFNA, PFOSA, and PFUdA were more predominantly and frequently detected than other PFASs in all samples, dominating PFAS patterns in aquatic products. The mean levels of ∑PFASs in different species followed the order: marine shellfish > marine crustaceans > fish > cephalopods > sea cucumber. Profiles of PFASs differ between species, suggesting species-specific accumulation plays a role. Various aquatic species are potential environmental bioindicators that signal individual PFAS contamination. For instance, clams can act as a potential PFOA bioindicator. High ∑PFAS levels in some sites (such as Binzhou, Dongying, Cangzhou, and Weifang) could be attributed to industrial activities involving fluoropolymer manufacture. The differences between PFAS concentrations and profiles in aquatic products across the study regions have been proposed as PFAS fingerprints of the Yellow-Bohai Sea coasts. Analyses of principal components and Spearman correlations indicated that the precursor biodegradation possibly contribute to C 8 –C 10 PFCAs in the study samples. This study reported a wide presence of PFASs in different species of aquatic products across the Yellow-Bohai Sea coasts. The potential health risks that PFASs pose in certain species (such as marine shellfish and marine crustaceans) should not be neglected. [Display omitted] • PFOA, PFOS, PFOSA, PFNA and PFUdA dominated PFAS patterns in aquatic products. • Different species of aquatic products have peculiar profiles. • Potential bioindicators that signal individual PFAS pollution were observed. • Region differences across Yellow-Bohai Sea coasts were proposed as PFAS fingerprints. [ABSTRACT FROM AUTHOR]

Biocompatible polymers, such as poly(ethylene glycol) (PEG), are of great significance in the development of bio-interfaces and biosensors, as they possess excellent biocompatibility and are easy for modification. A novel highly biocompatible polymer composite was synthesized herein through electrochemical polymerization of the conducting polymer poly(3,4-ethylenedioxythiophene) (PEDOT) and a PEG derivative, 4-arm PEG terminated with thiol groups. The electrodeposited conducting polymer composite of PEG doped PEDOT (PEDOT/PEG) exhibited flake-like nanostructure, large surface area and outstanding stability. In order to further immobilize antibodies, gold nanoparticles (AuNPs) were introduced to the PEDOT/PEG composite surface through their unique interaction with the thiol groups. AuNPs modified PEDOT/PEG provided a desirable support for the immobilization of various biomolecules such as antibodies for alpha fetoprotein (AFP), a vital tumor biomarker for liver cancer. The fabricated AFP biosensor demonstrated favorable selectivity, high sensitivity, and ultralow detection limit. Furthermore, owing to the presence of PEG polymers that are highly hydrophilic, such AuNPs/PEDOT/PEG based AFP biosensor also exhibited good anti-fouling ability, and it was capable of assaying target AFP in 10% (V/V) human serum samples, indicating highly feasible potential for clinical diagnosis. [ABSTRACT FROM AUTHOR]

Abstract: The flowers of Trollius species, named Jin Lianhua in Chinese, are widely used traditional Chinese herbs with vital biological activity that has been used for several decades in China to treat upper respiratory infections, pharyngitis, tonsillitis, and bronchitis. We developed a rapid and reliable method for simultaneous quantitative analysis of 19 flavonoids in trollflowers by using high-performance liquid chromatography (HPLC). Chromatography was performed on Inertsil ODS-3 C18 column, with gradient elution methanol–acetonitrile–water with 0.02% (v/v) formic acid. Content determination was used to evaluate the quality of commercial trollflowers from different regions in China, while three Trollius species (Trollius chinensis Bunge, Trollius ledebouri Reichb, Trollius buddae Schipcz) were explicitly distinguished by using hierarchical clustering analysis. The linearity, precision, accuracy, limit of detection, and limit of quantification were validated for the quantification method, which proved sensitive, accurate and reproducible indicating that the proposed approach was applicable for the routine analysis and quality control of trollflowers. [Copyright &y& Elsevier]

A rationally designed multifunctional polydopamine (PDA)-coated metal-organic frameworks (MOFs) biosensors for detection of miRNA-122 with Zn2+-triggered aggregation-induced enhancement (AIE) and synergistic chem-photothermal therapy in vitro was developed for the first time. Further, it was successfully used for enhanced fluorescence imaging of miRNA-122 in living cells. The pH-responsive MOFs structure was decomposed under the influence of acidic environment, and a large amount of free Zn2+ was released as the trigger agent for AIE signal amplification, realizing the ultra-sensitive detection of miRNA-122 and the accurate discrimination of the cells with different expression levels of miRNA-122, with the detection limit as low as 12.5 pM. Meanwhile, ZIF-8 nanoparticles with high loading rate can effectively deliver therapeutic drugs to achieve responsive release. In addition, the modification of versatile PDA-coating provides the biosensor with a faster drug release capability and photothermal conversion performance, demonstrating its superior synergistic chem-photothermal therapy performance. It is expected to play an important role in the integration of cancer diagnosis and synergistic therapy. A rationally designed multifunctional polydopamine (PDA) -coated metal-organic frameworks (MOFs) biosensors for detection of miRNA-122 with Zn2+-triggered aggregation-induced enhancement (AIE) and synergistic chem-photothermal therapy in vitro was developed for the first time. AIE-induced signal amplification ensured ultra-high detection sensitivity and successfully discriminated cells with different levels of miRNA-122 expression. More importantly, the introduction of PDA coating led to excellent photothermal conversion efficiency, enabling the developed multifunctional PDA-coated MOFs biosensor to achieve synergetic cancer chem-photothermal therapy. [Display omitted] • A rationally designed multifunctional PDA-coated MOFs biosensors for detection of miRNA-122 was developed. • The developed biosensor was based on Zn2+-triggered AIE and discriminated cells with different levels of miRNA-122. • The biosensor showed ultra-high sensitivity and excellent selectivity to miRNA-122, with a detection limit as low as 12.5 pM. • The biosensor provides an intelligent and rational strategy for cancer diagnosis and synergistic chem-photothermal therapy. [ABSTRACT FROM AUTHOR]

Biosensors have tremendous revolutionary potential for the precise location and rapid detection of biomarkers for human disease. However, the minimization of nonspecific protein adsorption interactions and surface contamination is critical for their application in complex media. We report herein, the antifouling interface was constructed by electrochemical copolymerization of poly (3,4-ethylenedloxythlophene) (PEDOT) and glycyrrhiza polysaccharide (GPS). Hydrophilic PEDOT/GPS can reduce the interference and nonspecific adsorption of biological protein macromolecules, which has been verified by electrochemical and fluorescent characterization. Gold nanoparticles (AuNPs) were subsequently modified onto PEDOT/GPS surface to attach biomacromolecules containing thiol groups. MicroRNA, the promising biomarker of a large numbers of genetic diseases, was used as the testing model. Due to the robust antifouling capability of PEDOT/GPS as well as high biocompatibility of GPS/AuNPs, the fabricated biosensor based on PEDOT/GPS/AuNPs demonstrated excellent sensing performance, such as a wide detection range (0.01 nM–10 nM), a low detection limit (300 fM) and high reproducibility, showing great potential of medical applications. Glycyrrhiza polysaccharide (GPS) and poly (3,4-ethylenedloxythlophene) (PEDOT) was constructed by electrochemical copolymerization. Hydrophilic PEDOT/GPS can reduce the interference and nonspecific adsorption of biological protein macromolecules. The biosensor based on PEDOT/GPS/AuNPs demonstrated excellent sensing performance, such as wide detection range, low detection limit and high reproducibility. Image 1 • Conducting polymer PEDOT/GPS was prepared by a simple electrochemical way. • The PEDOT/GPS demonstrated good conductivity and antifouling property. • The low fouling, label-free biosensor based on PEDOT/GPS has been constructed for MicroRNA. • The biosensor based on PEDOT/GPS/AuNPs has shown excellent sensing performances. [ABSTRACT FROM AUTHOR]

Conducting polymer polyaniline (PANI) nanowire arrays were electrochemically in situ synthesized on the surface of glassy carbon electrodes, which were modified with self-assembled multi-walled carbon nanotubes (CNTs) networks. The ordered PANI nanowire arrays and CNTs networks were integrated to create 3D nanostructured PANI/CNTs composites. Owing to their unique microstructure and conductivity, the PANI/CNTs nanocomposite exhibited excellent electrical properties such as remarkable supercapacitor performance and catalytic activity toward nitrite electrochemical reduction. It was found that the PANI/CNTs nanocomposite was capable of delivering high specific capacitance and showed excellent cycling stability. Moreover, it could be utilized as an electrochemical sensor for the detection of nitrite, with an outstanding sensitivity, low detection limit (6.1 μM, a signal to noise ratio of 3) and a fast response time of less than 5 s. [ABSTRACT FROM AUTHOR]

To study the interactions between natural compounds and deoxyribonucleic acid (DNA), a method has been established combining a high-performance liquid chromatography–diode array detector–multi-stage mass spectrometer with a fluorescence detector (HPLC–DAD–MS n –FLD). The FLD was used to monitor fluorescence intensity of the ethidium bromide–DNA (EB–DNA) complex when a compound separated by HPLC was introduced. This novel method was used to simultaneously obtain the HPLC fingerprint, UV spectra, MS n fragments and DNA-binding activity profile of various components in Folium Citri Reticulatae . As a result, 35 compounds were identified, of which 25 were found in the extract of Folium Citri Reticulatae for the first time, and 33 compounds showed DNA-binding activities, with the most active being feruloylhexaric and p -coumaroylhexaric acids. In addition, the precision, stability and reproducibility of this method were validated by two positive controls, quercetin and hesperidin. This new on-line method is accurate, precise and reliable for further high-throughput screening of DNA-binding compounds from food samples and other complex matrices. [ABSTRACT FROM AUTHOR]

[Display omitted] In this present study, a series of novel (E)-2-benzylidene- N -(3-cyano-4,5,6,7-tetrahydrobenzo[ b ]thiophen-2-yl)hydrazine-1-carboxamide derivatives against α-glucosidase were designed and synthesized, and their biological activities were evaluated in vitro and in vivo. Most of the designed analogues exhibited better inhibitory activity than the marketed acarbose, especially the most potent compound 7 with an IC 50 value of 9.26 ± 1.84 μM. The direct binding of 7 and 8 with α-glucosidase was confirmed by fluorescence quenching experiments, and the kinetic and molecular docking studies revealed that 7 and 8 inhibited α-glucosidase in a non-competitive manner. Cytotoxicity bioassay indicated compounds 7 and 8 were non-toxic towards LO2 and HepG2 at 100 μM. Furthermore, both compounds were demonstrated to have in vivo hypoglycemic activity by reducing the blood glucose levels in sucrose-treated rats. [ABSTRACT FROM AUTHOR]

[Display omitted] • An organic-inorganic hybrid nanomaterial (MGO@CD-CA-HA) has been constructed for synergistic photochemical therapy. • MGO@CD-CA-HA revealed satisfactory multiple-targeted features for hepatocellular carcinoma. • The camptothecin (CPT) loaded on MGO@CD-CA-HA exhibits NIR-triggered release behavior. • MGO@CD-CA-HA/CPT provides a significant inhibitory effect for the liver cancer cells in vitro and in vivo. Synergistic photochemical therapy with high performance and weak side effects is of great importance in hepatocellular carcinoma (HCC) treatment, therefore ingenious construct of nano-based therapy agents with accurate drug delivery and high photothermal conversion efficiency is of critical to the cancer therapy. Herein, an organic-inorganic hybrid nanomaterial (MGO@CD-CA-HA) has been constructed successfully by coating the β-cyclodextrin-cholic acid-hyaluronic acid polymer (CD-CA-HA) onto the Fe 3 O 4 -graphene oxide (MGO). The MGO@CD-CA-HA revealed satisfactory multiple-targeted features including the cholic acid supplied hepatic-target, CD44-receptor target of hyaluronic acid and magnetic target of Fe 3 O 4. Meanwhile, the hydrophobic antitumor drug camptothecin (CPT) was easily loaded by MGO@CD-CA-HA to form the MGO@CD-CA-HA/CPT nanocomposite, and the maximum theoretical adsorption capacity can reach 847.4 mg/g. Based on the facile photothermal response of MGO, the near-infrared radiation (808 nm) induced local hyperthermia was directly generated the apoptosis of tumor cells while triggered the release of CPT. Comparing with other kinds of cancer cells and normal hepatocyte cells, this PCT system provides a significant inhibitory effect for the liver cancer cells in vitro. Furthermore, the synergistic photochemical therapy presented the strong antitumor effect (the tumor inhibition rate > 90 %) in vivo. Thus, this study provided a promising multiple-targeted nanocarrier for chemo-photothermal combination therapy of liver cancer. [ABSTRACT FROM AUTHOR]

By using alkyl polyglycoside (APG) as foaming agent and natural gas as gas phase, the natural gas foam system was prepared, and the influence of alkyl chain length, metal cation valence and concentration, and polymer types on the foam stability was studied. By completely observing the volume and time required for the foam drainage liquid under different conditions, a foam drainage kinetics model was established. The drainage rate constant, the maximum drainage rate and its occurrence time during the foam drainage process can be acquired by derivation of the fitting function. The Arrhenius equation was adopted to fit the drainage rate constant at different temperature, and the drainage activation energy is obtained. The drainage process of foam was further analyzed from the perspective of kinetics. Moreover, the changes in geometric geometrics such as bubble number, particle size distribution frequency and the average diameter of the bubble in the decay process under different conditions was counted. According to the mathematical relationship between the average diameter and time, the Ostwald ripening rate and gas molecule diffusion constant are calculated. Finally, through the investigation of the interface properties and the micromorphology of the solution, the reasons for the above rules are explained. The research shows that: 1) the increase of the alkyl chain length of APG within a certain range (8–10.9) is beneficial to the improvement of the foam stability, and the continuous increase of chain length (10.9–12) is adverse to the foam stability, 2) the increase in the salinity of prepared water and the metal ions valence enhances the foam stability to a certain extent, 3) DG is more stable to APG foam than XG and KYPAM-6s. This study enriches the stability rules of APG foam with natural gas as the gas phase under different conditions, and provides ideas and methods for quantitatively analyzing the foam decay process from the perspectives of kinetics and statistics, which provides theoretical support for the application of natural gas foam in enhance oil recovery. • Establishment of mathematical model of CH 4 foam drainage kinetics. • Deeply studies of decay process of CH 4 foam associated with statistical method. • Explanation of the decay rule of CH 4 foam by the foam interface properties. • Enriched the stability rules of CH 4 foam under different conditions. [ABSTRACT FROM AUTHOR]