Paper-based test film material is widely used in a variety of test instruments for different applications. The enzyme activity test paper sheet is one of the most popularly used test papers. Here we present a novel fabrication of paper-based enzyme activity test paper without cationic resin added in.
View Article and Find Full Text PDFPolymeric membrane sensors based on molecular imprinted polymers (MIPs) have been attractive analytical tools for detecting organic species. However, the MIPs in electrochemical sensors developed so far are usually prepared by polymerization of pre-polymers and non-covalent adsorption on the surface of the working electrode. Meanwhile, the MIPs in the electrochemical sensors developed are typically made of a non-conductive polymer film.
View Article and Find Full Text PDFSpectrochim Acta A Mol Biomol Spectrosc
March 2024
Perfluorobutanesulfonyl fluoride (PBSF) has been used in the manufacture of fluorochemicals. Since PBSF is not biodegradable, the predicted environmental levels of PBSF are also expected to rise over time. In recent years, there has been a rise in the levels of PBSF in humans.
View Article and Find Full Text PDFThe main purpose of this paper was to systematically evaluate the effect of lignin, which was fractioned by green solvents into different molecular weights and used as polyol in the production of polyurethane foams (PUF). The results indicated that the foams prepared with the lower molecular weight lignin had uniform and complete pore structure and improved the mechanical strength. However, the higher molecular weight fraction lignin improved the density and thermal stability of the foam more significantly at the expense of inferior mechanical strength and pore structure deficiency.
View Article and Find Full Text PDFCurrently, the pharmaceutical and personal care products (PPCPs) have posed great challenge to advanced oxidation techniques (AOTs). In this study, we decorated sponge iron (s-Fe) with Cu and Pd (s-Fe-Cu-Pd) and further optimized the synthesis parameters with a response surface method (RSM) to rapidly degrade diclofenac sodium (DCF). Under the RSM-optimized conditions of Fe: Cu: Pd = 100: 4.
View Article and Find Full Text PDFSpectrochim Acta A Mol Biomol Spectrosc
April 2023
Chlorogenic acid(CGA) is the common active phenolic acid in Chinese medicinal materials such as honeysuckle and eucommia. It is a class of small molecules with multiple activities such as antioxidant, inhibiting cancer cells, lowering blood sugar and lowering blood pressure. In this paper, UV-vis spectroscopy, fluorescence spectroscopy, circular dichroism, molecular dynamics simulation and cyclic voltammetry (CV) electrochemical analysis were used to investigate the mechanism about interaction between CGA and BSA.
View Article and Find Full Text PDFHere, we report a novel aptasensor based on decahedral silver nanoparticles (AgNPs) enhanced fluorescence polarization (FP) for detecting PCB-77. Using aptamer modified AgNPs hybridized with DNA sequence labeled fluorescent group as an analytical probe, polychlorinated biphenyls (PCB-77) could be detected with high sensitivity and selectivity. The linear range of determination was 0.
View Article and Find Full Text PDFThe molecular weight is one of the most important factors influencing the utilization of industrial lignin obtained from chemical pulping process. In this paper, a facile operative green solvent system was successfully developed for molecular weight-controllable fractionation of industrial alkali lignin (IAL) at room temperature. The results showed that through adjusting the ratio of water, ethanol and γ-Valerolactone (GVL), the industrial lignin was fractionated into six levels with molecular weight stepwise controllable from low to high.
View Article and Find Full Text PDFDespite the alleviation of particulate matter (PM), the ambient ozone (O) concentration is continuously increasing in Hunan province where the investigation of O pollution has been rarely reported. Accordingly, the spatio-temporal evolution of O pollution was first analyzed based on hourly air quality data observed by national monitoring stations from 2015 to 2020 over 14 cities in Hunan province. Afterwards, the combination of meteorological data from the European Center for Medium-range Weather Forecast (ECMWF) and the generalized additive model (GAM) was applied to investigate the driving factors of the O long-term trend during this period.
View Article and Find Full Text PDFEnzymatic hydrolysis is a method to generate biofuel from biomass, and autohydrolysis is a popular method to pretreat biomass prior to enzymatic hydrolysis. The primary aim of the present study was to determine the role of lignin produced in the autohydrolysis process on the enzymatic hydrolysis of biomass. The HSQC and P NMR analyses confirmed that β-O-4 of lignin was reduced, while β-5, β-β, and S/G-ratio of lignin were increased with intensifying the hydrolysis intensity.
View Article and Find Full Text PDFAptamer-functionalized nanoparticles have been widely studied as targeted probes in biomedical applications for targeted therapy and imaging. The rigidity of the nanoparticle could stabilized the spatial structure of the aptamer, ensuring the selectivity and affinity for target recognition in the complex environment. The main aim of this article study was to explore the effect of the spatial structure of aptamer in the interaction between aptamer nanoprobes and receptors.
View Article and Find Full Text PDFKlebsiella pneumoniae carbapenemase 2 (KPC-2) is a serine β-lactamase that can hydrolyze almost all β-lactam antibiotics. The drug resistant problem of bacteria expressing carbapenemases is currently a global problem, therefore, rapid and specific detection of pathogenic bacteria is urgent. In order to obtain an aptamer that can specifically recognize bacteria expressing KPC-2, we have established a method called Precision-SELEX.
View Article and Find Full Text PDFAn analytical method for screening aptamers for different recognition sites in lactoferrin (Lac) molecules has been developed based on Surface Plasmon Resonance imaging (SPRi), combined with the cluster classification calculation of a quasi-aptamer library strategy and molecular docking simulation analysis. Using the software simulation, a homology analysis was performed on the selected quasi-aptamer sequences, which could be divided into 8 different families. Based on the principle of biomolecular recognition, a label-free, high-throughput dual immune site screening method was established, in which the nucleic acid aptamers of recognizing ability for lactoferrin molecules were fixed onto the surface of the SPRi sensor chip and could bind to the lactoferrin molecules.
View Article and Find Full Text PDFBackground: Lumbar disc herniation (LDH) places a serious burden on the daily lives and socioeconomics of people. Although the pathogenesis of LDH is complex, genetic factors such as single nucleotide polymorphisms (SNPs) may affect the risk of developing LDH. In the present study, we aimed to elucidate the effect of RAB40C SNPs on the risk of LDH in the Chinese Han population.
View Article and Find Full Text PDFWhen using a combination of pre-extraction and chemical pulping, a high yield of sugar recovery and minimal negative effect on the subsequent pulping step are expected. In this work, the P factor was utilized to investigate the effect of auto-hydrolysis severity on sugar recovery, removal of the main component, and impact on the kraft pulping of acacia wood chips. Using a P factor of 235, 84.
View Article and Find Full Text PDFA highly efficient method for eliminating terminal fixed region interference of aptamer with real-time monitoring of the SELEX process was described by silver decahedra nanoparticles probe (Ag-A-RP(15)) capture and block the terminal fixed region candidates. A microarray chip was developed by immobilization of target protein (lipocalin-1 (LCN-1)) and control proteins (Human serum albumin (HSA), Bovine serum albumin (BSA) and Holo-transferrin) on the biochip surface. The nucleic acid pool was first incubated with target and then captured by hybridization with Ag-A-RP(15).
View Article and Find Full Text PDFPurpose: Circular RNAs (circRNAs) are a class of noncoding RNAs that can regulate gene expression at the post-transcriptional level. The contribution of circRNAs in the regulation of granulosa cells (GCs) functions is not yet clear. The aim of this study was to analyze circRNA expression in adult and neonate ovaries, uncover the biological roles of circ_0002861 (circEGFR) and identify the mechanism by which it modulates follicular development.
View Article and Find Full Text PDFVia the facile ring-opening reaction of epoxy groups with quinine, a novel polymer monolith with quaternary ammonium for reversed-phase/strong anion-exchange mixed-mode has been fabricated for pressurized capillary electrochromatography (pCEC). Optimization on the preparation of quinine-modified monoliths has been investigated, and characteristics including morphology, permeability, mechanical stability, reproducibility, and column performance have been also studied. Active quaternary ammonium groups were conveniently produced to generate cationic action sites and stable anodic electroosmotic flow.
View Article and Find Full Text PDFA highly efficient method for aptamer screening with real-time monitoring of the SELEX process was described by silver decahedra nanoparticles (Ag-NPs) enhanced surface plasmon resonance imaging (SPRI). A microarray chip was developed by immobilization of target protein (Lactoferrin (Lac)) and control proteins (α-lactalbumin (α), β-lactoglobulin (β), casein, and bovine serum albumin (BSA)) on the biochip surface. Ag-NPs were conjugated with an ssDNA library (lib) (Ag-NPs-library) that consisted of a central 40 nt randomized sequence and a 20 nt fixed primer sequence.
View Article and Find Full Text PDFHere we report a novel type of bivalent aptasensor based on silver-enhanced fluorescence polarization (FP) for detection of lactoferrin (Lac) in milk powder with high sensitivity and specificity. The novel two split aptamers were obtained from the aptamer reported in our previous SELEX (systematic evolution of ligands by exponential enrichment) selection, and their minimal structural units were optimized on the basis of their affinity and specificity. Also, dual binding sites of split aptamers were verified.
View Article and Find Full Text PDFWe developed an efficient and fast method based on a protein microarray integrated with a microfluidic chip for the process of SELEX (systematic evolution of ligands by exponential enrichment). Lactoferrin from bovine milk was used as a target protein, while bovine serum albumin (BSA), α-lactalbumin, β-lactoglobulin and casein were used as negative proteins. They were separately dotted and immobilized to prepare the protein microarray and the resulting microarray was further integrated into a microfluidic chip for the SELEX (PMM-SELEX) process.
View Article and Find Full Text PDFPrevious studies have shown that octamer-binding transcription factor 4 (Oct4) plays a significant role in early embryonic development of mammalian animals, and different expression levels induce multi-lineage differentiation which are regulated by DNA methylation. To explore the relationship between the methylation pattern of gene exon 1 and embryonic development, in this work, five different tissues (heart, liver, lung, cerebrum and cerebellum) from three germ layers were chosen from low age (50-60 d) and advanced age (60-70 d) of fetal cattle and the differences between tissues or ages were analyzed, respectively. The result showed that the DNA methylation level of gene exon 1 was significant different (<0.
View Article and Find Full Text PDFJ Anim Sci Biotechnol
December 2015
Background: Identification of genetic variants, including SNPs (Single Nucleotide Polymorphisms), CNVs (Copy Number Variations) and alternative splicing, within functional genes has received increasing attention in animal science research. HGF (Hepatocyte Growth Factor) is a very important growth factor that works as a mitogen or a morphogen during tissue growth, development and regeneration. However, to date, the functions of genetic variants within the bovine HGF gene, particularly their effects on mRNA expression, have not been determined well.
View Article and Find Full Text PDFThe AT motif-binding factor (ATBF1) not only interacts with protein inhibitor of activated signal transducer and activator of transcription 3 (STAT3) (PIAS3) to suppress STAT3 signaling regulating embryo early development and cell differentiation, but is required for early activation of the pituitary specific transcription factor 1 (Pit1) gene (also known as POU1F1) critically affecting mammalian growth and development. The goal of this study was to detect novel nucleotide variations and haplotypes structure of the ATBF1 gene, as well as to test their associations with growth-related traits in goats. Herein, a total of seven novel single nucleotide polymorphisms (SNPs) (SNP 1-7) within this gene were found in two well-known Chinese native goat breeds.
View Article and Find Full Text PDFSomatic cell reprogramming has generated enormous interest, following the first report of generation of induced pluripotent stem cells (iPSCs) from mouse fibroblasts, but the integration of viral transgenes into the genome is unlikely to be accepted. Given these safety considerations, a method for virus-free transient gene expression from suspension-adapted Sf9 insect cells was developed. Here, we expressed transactivator of transcription (TAT)-fused proteins, Sox2, Oct4, Lin28, and Nanog in Sf9 cells using the baculovirus expression vector system (BEVS).
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