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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]

Abstract: The study of the interaction between drugs and DNA is an important way to understand the role of drug molecules. A novel online analytical method for this purpose combining high-performance liquid chromatography-diode array detector-electrospray ionization-ion-trap time-of-flight mass spectrometry (HPLC-DAD-ESI-IT-TOF-MS n ) and DNA-ethidium bromide detection with a fluorescence detector (DNA–EB-FLD) was firstly developed, which could rapidly identify the chemical constituents and obtain the profile related to DNA binding activity. This method has been applied for a precise or probable identification of the chemical constituents by ultraviolet (UV) absorption and MS n data analysis, while the DNA binding profile has been characterized by directly measuring the fluorescence intensity of compound-DNA–EB. Using this method, Trollius chinensis Bunge was studied and 18 constituents were identified by MS n data; six of them (4′-methoxy-2″-O-(2‴-methylbutyryl)vitexin,2″-O-(3‴-methoxycaffeoyl)vitexin) and 4′-methoxy-2″-O-(2‴-methylbutyryl)orientin,acacetin-7-O-rutinoside,quercetin-3-O-xylosylglucoside,quercetin-3-O-arabinosylglucoside) were identified for the first time in T. chinensis Bunge, and 16 constituents accounted for its activity of binding to DNA. The established (HPLC-DAD-ESI-IT-TOF-MS n DNA–EB-FLD) system has proved to offer a useful strategy for correlating the chemical profile with the binding to DNA activities of the components without their isolation and purification, and may be used for multicomponent analysis of active substances in other herbs. [Copyright &y& Elsevier]

Atherosclerosis (AS) constitutes a major threat to human health, yet most current therapeutics are hindered in achieving desirable clinical outcomes by low bioavailability or serious side effects. Herein, we constructed an enzyme-responsive and macrophage-targeting drug delivery system (SIM@HA-MSN) which can potentially modulate the microenvironment of the atherosclerotic plaques characterized by excessive inflammation and overexpression of hyaluronidase (HAase) for precise AS treatment. More specifically, mesoporous silica nanoparticles (MSNs) were loaded with a lipid-lowering drug simvastatin (SIM) and further gated with hyaluronic acid (HA) coating, which endowed the nanosystem with HAase responsiveness and targetability to inflammatory macrophages. Our results showed that a high loading efficiency (>20%) and excellent enzyme-responsive release of SIM were simultaneously achieved for the first time by silica-based nanocarriers through formulation optimizations. Moreover, in vitro experiments confirmed that SIM@HA-MSN possessed robust targeting, anti-inflammatory, and anti-foaming effects, along with low cytotoxicity and excellent hemocompatibility. In addition, preliminary animal experiments demonstrated the as-established nanosystem had a long plasma-retention time and good biocompatibility in vivo. Taken together, SIM@HA-MSN with HA playing triple roles including gatekeeping, lesion-targeting, and long-circulating holds great potential for the management of atherosclerosis. [ABSTRACT FROM AUTHOR]

Ultrasensitive and low-fouling microRNA electrochemical biosensors were successfully constructed by introducing thiol-terminated antifouling molecules (peptide sequence, polyethylene glycol, or mercapto alcohol) onto the surface of polyaniline-modified electrodes. For the three kinds of antifouling materials investigated, the newly designed and synthesized peptide exhibited superior antifouling ability to others, and it could effectively reduce the nonspecific adsorption of proteins and even prevent the fouling effect of serum. Compared with microRNA biosensors without antifouling capability, or those modified with polyethylene glycol or mercapto alcohol, the biosensor modified with the designed zwitterionic peptide showed the highest specificity for single-base mismatch, three-base mismatch, and completely complementary microRNAs. Most interestingly, the experimental results indicated that the introduction of antifouling molecules to the sensing interfaces did not significantly change the sensitivity of the biosensor. The strategy of constructing antifouling biosensors based on newly synthesized zwitterionic peptides and conducting polymers can be promisingly extended to the development of other electrochemical sensors and biosensors without encountering biofouling. [ABSTRACT FROM AUTHOR]

An ultrasensitive biosensor for alpha-fetoprotein was developed based on electrochemically synthesized polyaniline (PANI) nanowires, which were functionalized with gold nanoparticles (AuNPs) and polyethylene glycols (PEG). The prepared PEG/AuNPs/PANI composite, combining the electrical conductivity of the AuNPs/PANI with the robust antifouling ability of PEG, offered an ideal substrate for the development of low fouling electrochemical biosensors. Alpha-fetoprotein (AFP), a well-known hepatocellular carcinoma biomarker, was used as a model analyte, and its antibody was immobilized on the PEG/AuNPs/PANI for the construction of the AFP immunosensor. Using the redox current of PANI as the sensing signal, in addition to the good biocompatibility of PEG/AuNPs and the anti-biofouling property of PEG, the developed immunosensor showed improved biosensing performances, such as wide linear range and ultralow detection limit (0.007 pg mL −1 ). More importantly, it is label-free, reagentless and low fouling, making it capable of assaying AFP in real serum samples without suffering from significant interference or biofouling. [ABSTRACT FROM AUTHOR]

Artemether, a natural derivative of artemisinin, serves an antitumor role in numerous types of cancer. However, the role and mechanism of action of artemether in hepatocellular carcinoma (HCC) has remained elusive. The present study aimed to investigate whether artemether is able to inhibit the proliferation, invasion and migration of HCC cells by targeting cytochrome P450 family 2 subfamily J member 2 (CYP2J2). Cell Counting Kit-8 (CCK-8) and colony-formation assays were used to examine cell viability. Wound-healing and Transwell assays were used to evaluate the cell invasion and migration ability. The expression levels of the epithelial-mesenchymal transition-related proteins E-cadherin, N-cadherin and vimentin were detected via western blot analysis. To determine the mechanism of the inhibitory effect of artemether on HCC, CYP2J2 was overexpressed and its expression in cells treated with artemether was confirmed using reverse transcription-quantitative PCR and western blot analysis. The effects of artemether on the viability, proliferation and migration of HCC cells overexpressing CYP2J2 were detected using CCK-8, colony-formation, wound-healing and Transwell assays, respectively. Artemether was demonstrated to exert a significant inhibitory effect on the proliferation, invasion and migration of HCC cells. Furthermore, artemether also inhibited CYP2J2 expression in Hep3B2.1-7 cells and CYP2J2 overexpression reversed the inhibitory effect of artemether on the proliferation, invasion and migration of HCC cells. Overall, these results indicated that artemether may inhibit HCC cell proliferation, invasion and migration via targeting CYP2J2. These findings may provide potential targets for future HCC therapeutics. [ABSTRACT FROM AUTHOR]

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]

Electrochemical CO2 reduction reaction (CO2RR) is eliciting considerable attention in relation to the carbon cycle and carbon neutrality. As for the practical application of CO2RR, the electrocatalyst is a crucial factor, but, even so, designing and synthesizing an excellent catalyst remains a significant challenge. In this paper, the coordination compound of Ni ions and dimethylglyoxime (DMG) was employed as a precursor to modify reduced graphene oxide (rGO) for CO2RR. The textural properties and chemical bonds of as-obtained rGO, N–C–rGO, Ni–rGO, Ni–N–C, and Ni–N–C–rGO materials were investigated in detail, and the role of Ni, N–C, and rGO in the CO2RR were researched and confirmed. Among all the catalysts, the Ni–N–C–rGO showed the optimal catalytic activity and selectivity with a high current density of 10 mA cm−2 and FE(CO)% of 85% at −0.87 V vs. RHE. In addition, there was no obvious decrease in activity for 10 h. Therefore, the Ni–N–C–rGO is a promising catalyst for CO2RR to CO. [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 poly(3,4-ethylenedioxythiophene) (PEDOT) possesses high electrical conductivity but limited catalytic activity, and doping with suitable nanomaterial to fabricate multifunctional electrical substrate is an ideal approach to broaden the application of PEDOT. Herein, Au@graphene (AG) core-shell nanoparticles with high conductivity, catalytic activity and stability, were synthesized and doped into PEDOT to build PEDOT/AG nanocomposite material by a facile electrodeposition method. The PEDOT/AG composite exhibited high conductivity and excellent catalytic activity toward the redox of paracetamol, and owing to the presence of AG nanoparticles, the electrochemical signals and peak profiles of paracetamol at the PEDOT/AG modified electrode were significantly improved. Under optimum conditions, the PEDOT/AG modified electrode exhibited high sensitivity to paracetamol over a wide linear range of concentrations from 0.15 μM to 5.88 mM, with a detection limit of 41 nM (S/N = 3). Furthermore, the fabricated sensor exhibited high selectivity and long-term stability, and was capable of detecting paracetamol in real pharmaceutical samples with satisfying accuracy. [ABSTRACT FROM AUTHOR]

Herein, a novel near-infrared (NIR) light-driven photoelectrochemical (PEC) biosensor based on NaYF 4 :Yb3+, Er3+@Bi 2 MoO 6 @Bi (NYF@BMO@Bi) nanocomposites was elaborately developed to achieve highly sensitive detection of microRNA-155 (miRNA-155). To realize signal enhancement, the coupled plasmonic bismuth (Bi) nanoparticles were constructed as an energy relay to facilitate the transfer of energy from NaYF 4 :Yb3+, Er3+ to Bi 2 MoO 6 , ultimately enabling the efficient separation of electron-hole pairs of Bi 2 MoO 6 under the irradiation of a 980 nm laser. For constructing biosensing system, the initial signal was firstly amplified after the addition of alkaline phosphatase (ALP) in conjunction with the biofunctionalized NYF@BMO@Bi nanocomposites, which could catalyze the conversion of ascorbic acid 2-phosphate into ascorbic acid, and then consumed the photoacoustic holes created on the surface of Bi 2 MoO 6 for the enlarging photocurrent production. Upon addition of target miRNA-155, the cascade signal amplification process was triggered while the ALP-modified DNA sequence was replaced and then followed by the initiation of a simulated biocatalytic precipitation reaction to attenuate the photocurrent response. On account of the NIR-light-driven and cascade amplifications strategy, the as-constructed biosensor was successfully utilized for the accurate determination of miRNA-155 ranging from 1 fM to 0.1 μM with a detection limit of 0.32 fM. We believed that the proposed nanocomposites-based NIR-triggered PEC biosensor could provide a promising platform for effective monitoring other tumor biomarkers in clinical diagnostics. [ABSTRACT FROM AUTHOR]

Oxidative stress plays an important role in pathology, and contributes to a variety of diseases, including inflammation, neurodegenerative diseases, and cancer. Research studies have shown that acetylcholinesterase (AChE) plays a key role in regulating oxidative stress. However, an effective analytical method for real-time monitoring of AChE under oxidative stress is still lacking. Currently, fluorescent probes based on dual sensing mechanisms have attracted great attention by combining and amplifying the advantages of both mechanisms. In this work, two NIR fluorescent probes (SNCN-AE and SNC-AE) that combined ESIPT and ICT processes were designed and synthesized for accurate detection of AChE activity. After the probes reacted with AChE, the strong electron push-pull effect enhanced the ICT process, which further synergized with the ESIPT effect, resulting in a distinct NIR fluorescence signal accompanied by a large Stokes shift. In particular, SNCN-AE showed better detection performance of fast response, good photostability and low cytotoxicity, which was highly suitable for imaging of endogenous AChE in living system. Importantly, SNCN-AE had been successfully applied for monitoring AChE under oxidative stress in PC12 cells and zebrafish model. These excellent properties made probes the promising tools for studying oxidative stress and related diseases. [Display omitted] • NIR fluorescent probes that combined ESIPT and ICT processes were designed for accurate detection of AChE. • Probes showed high sensitivity and good selectivity toward AChE accompanied by a large Stokes shift. • Probe SNCN-AE with good photostability and low cytotoxicity has been applied for imaging of endogenous AChE. • Probe SNCN-AE could monitor AChE levels under oxidative stress in cells and zebrafish model. [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]

Herein, a universal strategy for the construction of highly sensitive and low fouling biosensors was proposed based on antifouling peptides conjugated with recognizing DNA probes. The peptide-DNA conjugate was formed through a reagent-free click reaction between a typical DNA aptamer modified with 5′-dibenzocyclooctyne (DBCO) and the designed antifouling peptide terminated with biotin and the azide group at its two ends. With the assistance of streptavidin (SA), the electrochemical biosensor was constructed via immobilization of the straight peptides and peptide-DNA conjugates in sequence onto the electrode surface modified with electrodeposited poly(3,4-ethylenedioxythiophene) (PEDOT) and gold nanoparticles (AuNPs). The prepared biosensor exhibited excellent antifouling performances in various human bodily fluids such as serum, sweat and urine, with a wide linear response range for CA125 from 0.01 U mL−1 to 1000 U mL−1, and a low limit of detection of 0.003 U mL−1. Combining the advantages of the antifouling peptide and recognizing DNA probe, this sensing strategy was capable of assaying CA125 in undiluted human serum, and it also offered a highly promising way for the development of different antifouling biosensors through the conjugation of antifouling peptides with various DNA probes. [ABSTRACT FROM AUTHOR]

In this work, we fabricated a monodisperse nanocomposite by coating gold nanorods (AuNRs) with a layer of biocompatible, stable carbon, obtaining AuNR@Carbon core-shell nanocapsules, which without any functionalization could be used as a molecule loading material due to its high surface areas. In this system, the AuNR core had a high-absorption cross section for conversion of near-infrared light to heat, which could be explored for local hyperthermia. The carbon shell, which was biocompatible and stable even under concentrated acidic and alkaline conditions, was able to adsorb molecules with π-π interactions or electrostatic interactions. In comparison with AuNR@SiO, AuNR@Carbon nanocapsules demonstrate the following merits: (1) simple and green synthesis method, (2) far more stable with respect to high-temperature stability and (3) larger molecule loading capacity, which indicate great potential in the biomedical applications. [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]

• An TPE based novel signal off ECL sensor was constructed for ALP detection. • Expanded the application of TPE in water phase. • The emitter of TPE-pho has the advantages of simple synthesis, high stability. • The ECL sensor exhibited a low detection limit of 0.037 U/L. The aggregation-induced electrochemiluminescence (ECL) of phosphate-containing tetraphenylethene (TPE) for alkaline phosphatase (ALP) activity detection in aqueous solution was investigated for the first time. By using the triethylamine (TEA) as the coreactant, the aggregation-induced emission (AIE) emitters TPE-pho exhibited a strong anode aggregation state electrochemical luminescence. In the presence of ALP, the phosphoric group was derived from the original conjugated structure by enzymatic lysis leading to a decreasing ECL signal. High selectivity and sensitivity to ALP were showed by this new luminescent material applied in the ECL system. The detection limit in Tris-HCl buffer was found to be 0.037 U/L, and the linear quantitative range was 0.1–6.0 U/L. This method was also tried to be used in the human serum and cell experiments and successfully demonstrated its potential application in clinical analysis of ALP levels in cell and serum. [ABSTRACT FROM AUTHOR]

• Optimizing the photoelectric properties of BiVO 4 by doping elements. • The aza-cope rearrangement reaction between the recognition group and formaldehyde. • The aza-cope rearrangement reaction improved selectivity and speed to formaldehyde. • Via calculations, the limitation of detection is 0.4 μM. A photoelectrochemical (PEC) sensor was designed by connecting an organic recognize group 1-(4-(3-aminopropoxy)phenyl)-N-(4-nitrobenzyl)but-3-en-1-amine (FOP-1) to a modified photoelectric nanomaterial Pt-BiVO 4 nano flowers (NFs) for ultra-sensitive and highly selective detection of formaldehyde (FA). The steric hindrance of the FOP-1 and the strong electron-withdrawing group nitro blocked the transfer of electrons excited to the electrode under illumination, resulting in a decrease in photocurrent. With the addition of FA, it triggered a specific aza-cope remake reaction (2-aza-cope sigmatropic rearrangement), leading to N-(4-nitrobenzyl)but-3-en-1-amin (NBEA) group removed, the steric hindrance weakened, the electron-withdrawing effect decreased, and the photocurrent signal recovered obviously. The entire sensor shows good stability and repeatability, excellent selectivity for FA, its detection limit is 0.4 μM, and the linear range is 1–1000 μM, Moreover, endogenous FA released from live MCF-7 cells and the real mice serum samples were monitored successfully by the PEC sensor, indicating its practicality potential in biological cytology and pathophysiology. [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]

Aptamers are short single-stranded RNA or DNA molecules that can recognize a series of targets with high affinity and specificity. Known as "chemical antibodies", aptamers have many unique merits, including ease of chemical synthesis, high chemical stability, low molecular weight, lack of immunogenicity, and ease of modification and manipulation compared to their protein counterparts. Using aptamers as the recognition groups, fluorescent aptasensors provide exciting opportunities for sensitive detection and quantification of analytes. Herein, we give an overview on the recent development of aptamer-based fluorescent sensors for the detection of cancer biomarkers. Based on various nanostructured sensor designs, we extended our discussions on sensitivity, specificity and the potential applications of aptamer-based fluorescent sensors in early diagnosis, treatment and prognosis of cancers. Schematic illustration of aptamer-based fluorescent sensors for the detection of cancer biomarkers. Unlabelled Image • This review summarize the recent advances of fluorescent aptasensors for the detection of cancer biomarkers. • The detection strategies of various fluorescent aptasensors are discussed. • Future perspectives and possible challenges in this area are outlined. [ABSTRACT FROM AUTHOR]

• A NIR fluorescent probe (Ex545 nm, Em 676 nm) for accurate detection of GLU was reported. • The probe showed a large Stokes shift (131 nm) for specific detection of GLU. • The probe could distinguish GLU-overexpressed cancer cells from normal cells. • The probe was suitable for noninvasive imaging in mice model and excised intestinal. β-Glucuronidase (GLU) plays a vital role in the growth, migration, angiogenesis, and metastasis of tumors. The reliable detection of GLU is an effective approach for early diagnosis of numerous disease such as cholelithiasis and colorectal cancer. In this work, a near-infrared fluorescent probe (DP-GLU) with a large Stokes shift was rationally designed for accurate detection of GLU in living cells and mouse models. DP-GLU was composed of two moieties: dicyanoisophorone as NIR fluorophore and enzyme substrate as GLU recognizable group. Upon reaction with GLU, DP-GLU rapidly displayed a strong emission at 676 nm and the Stokes shift could reach 131 nm. DP-GLU also exhibited high sensitivity toward GLU, and the linearity was fitted in the concentration range of 0−100 μg/L with the detection limit as low as 1.45 × 10−2 μg/L. Furthermore, DP-GLU was used for distinguishing GLU-overexpression tumor cells from normal cells and revealed functions of noninvasive tracking GLU levels in mouse tumor models. Remarkably, DP-GLU was great potential application for cancer imaging in the early diagnoses and therapies of pathologies, which could obtain a comprehensive of the physiological functions of GLU. [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]

• A FRET based ratiometric two-photon fluorescent probe FTR-βgal has been developed. • The probe was applied to detect β-galactosidase with the ratio signal rapid variation. • The probe could distinguish overexpressed β-galactosidase cells from normal cells. • The probe was used for imaging of β-galactosidase in tissues with deep penetration. In vivo measurement of abnormal β-galactosidase (β-gal) in living cells and tissues is urgently required for early diagnosis and treatment of primary ovarian cancer. Herein, a FRET-based ratiometric two-photon fluorescent probe FTR-βgal with a large emission shift, rapid response and low cytotoxicity was developed for sensitively detecting β-gal activity in vivo. FTR-βgal was designed with a naphthalene derivative as the energy donor and a rhodol derivative as the energy acceptor, which provided an efficient FRET strategy. Remarkably, FTR-βgal was successfully applied in TP imaging of β-gal with the ratio signal rapidly transform from 0.15 to 5.9 (∼40-fold) between 540 nm and 450 nm. Furthermore, FTR-βgal was used to visualize β-gal levels in tumor upon tissue penetration of 30–150 μm achieved. Therefore, FTR-βgal was applicable for clinical detection in living cells and tissues as a promising strategy for diagnosis of various associated cancers. [ABSTRACT FROM AUTHOR]

An electrochemical sensor that can resist biofouling even when operated in complex biological medium is developed for the determination of dopamine. It is based on the use of the conducting polymer poly(3,4-ethylenedioxythiophene) (PEDOT) that is doped with the water insoluble ionic liquid (IL), 1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide. A glassy carbon electrode modified with PEDOT/IL is shown to enable accurate determination of dopamine, as a model analyte in the presence of high concentrations of proteins, and resist biological fouling even in native serum. It exhibited a low limit of detection of 33 nM for the detection of dopamine, with a wide linear range from 0.2 to 328 μM (at 0.2 V vs. saturated calomel electrode). The PEDOT/IL modified glassy carbon electrode has a porous microstructure, high electrical conductivity and good stability. The sensor can be used to quantify dopamine in human urine samples with satisfying accuracy. Graphical abstract An antifouling electrochemical sensor capable of detecting target in complex biological samples was developed based on the use of a conducting polymer (PEDOT) that was doped with a water insoluble ionic liquid. [ABSTRACT FROM AUTHOR]