The Infona portal uses cookies, i.e. strings of text saved by a browser on the user's device. The portal can access those files and use them to remember the user's data, such as their chosen settings (screen view, interface language, etc.), or their login data. By using the Infona portal the user accepts automatic saving and using this information for portal operation purposes. More information on the subject can be found in the Privacy Policy and Terms of Service. By closing this window the user confirms that they have read the information on cookie usage, and they accept the privacy policy and the way cookies are used by the portal. You can change the cookie settings in your browser.
Detection of specific biomarkers in cell membranes is critical for cell biology and disease theranostics. Here we develop a versatile terminal protection assay strategy for wash-free quantification and imaging of cell surface proteins using small molecule-linked DNA with programmable signal sequences. DNA probes are designed to link to a small molecule ligand at 3′ end for specific recognition of...
5′-Polynucleotide kinase (PNK) is a crucial enzyme that catalyzes the phosphorylation of nucleic acid with 5′-OH termini and this phosphorylation reaction has been involved in many important cellular activities. The evaluation of PNK activity has received an increasing attention due to the significance of PNK. Here, the polydopamine nanospheres (PDANS) could adsorb single-stranded DNA (ssDNA) through...
The aim of the present work was to develop a rapid and interference-free method based on liquid chromatography-mass spectrometry (LC-MS) for the simultaneous determination of nine B-group vitamins in various energy drinks. A smart and green strategy that modeled the three-way data array of LC-MS with second-order calibration methods based on alternating trilinear decomposition (ATLD) and alternating...
When using circular dichroism (CD) spectroscopy for quantitative analysis, the samples to be analyzed must be free of light-absorbing interferences. However, in real-world samples, the presence of background absorbers is practically unavoidable. The difference in the matrices between the real-world samples to be analyzed and the standard samples (on which either univariate or multivariate calibration...
GC-MS urinary metabolomic analysis coupled with chemometrics is used to detect inborn errors of metabolism (IEMs), which are genetic disorders causing severe mental and physical debility and even sudden infant death. Orthogonal partial least squares discriminant analysis (OPLS-DA) is an efficient multivariate statistical method that conducts data analysis of metabolite profiling. However, performance...
A turn-on fluorescent probe (Naphsulf-O) for hydrazine was developed by protecting the hydroxy group of the fluorophore 6-acetyl-2-hydroxynaphthalene via O-4-nitrobenzenesulfonylation, where 4-nitrobenzene was used as a fluorescence quenching moiety as well as an electrophile. Upon nucleophilic aromatic substitution (NAS) reaction of hydrazine toward the probe, the protecting group was removed and...
Most of the proteins locate more than one organelle in a cell. Unmixing the localization patterns of proteins is critical for understanding the protein functions and other vital cellular processes. Herein, non-linear machine learning technique is proposed for the first time upon protein pattern unmixing. Variable-weighted support vector machine (VW-SVM) is a demonstrated robust modeling technique...
The study of spatial distribution characteristics of the adsorbed compounds for absorbent materials has significant importance in understanding the behaviors of aerosols while they migrating in the absorbent materials. Herein, for the first time, desorption corona beam ionization–mass spectrometry (DCBI–MS) has proposed for direct in-situ analysis of adsorbed aerosol for absorbent materials. DCBI...
DNA sequences with guanine repeats can be induced to form G-quartets that adopt G-quadruplex structures in the presence of thioflavin T (ThT). ThT plays a dual role of inducing DNA sequences to fold into quadruplex structures and of sensing the change by its remarkable fluorescence enhancement. ThT binding to the DNA sequences with guanine repeats showed highly specific fluorescence enhancement compared...
A novel intrinsic fluorescence method for the direct determination of l-phenylalanine, l-tyrosine, and l-tryptophan in human plasma is presented. By using fluorescence excitation–emission–pH–sample data array in combination with four-way calibration method based on the quadrilinear component model, the proposed approach successfully achieved quantitative analysis of the aromatic amino acids in human...
This work presents a novel approach for simultaneous determination of butylated hydroxyanisole (BHA) and propyl gallate (PG) in a very interfering environment by combining the sensitivity of molecular fluorescence and the selectivity of the second-order calibration method. The excitation–emission fluorescence matrix data are processed by applying the second-order calibration method based on the self-weighted...
Rapid, sensitive and quantitative assays for peptide hydrolysis enzymes are of paramount importance for drug development and in the diagnosis of disease. Here, we proposed a novel biosensor for sensitive and selective active screening of peptidases. This strategy relies on the proteolysis-mediated protection of gold nanoparticles (AuNPs) that were decorated with biotin-labeled substrate peptides and...
A new and facile strategy using double-stranded DNA-copper nanoparticles (dsDNA-Cu NPs) as fluorescence reporters for the highly sensitive and selective detection of l-histidine was demonstrated. In the dsDNA-Cu NPs-based sensing system, the fluorescence was quenched considerably upon the addition of l-histidine. Under the optimized experimental conditions, the probe exhibits excellent performance...
In this work, with the purpose of developing an effective and inexpensive method, excitation–emission matrix fluorescence data and second-order calibration method based on the self-weighted alternating trilinear decomposition (SWATLD) algorithm were combined for simultaneous determination of 2-naphthoxyacetic acid (NOA) and 1-naphthaleneacetic acid methyl ester (NAAME) in environmental samples, i...
Activity screening of DNA base excision repair (BER) enzymes is a crucial step for understanding numerous fundamental biochemical processes. A novel label-free homogeneous technique is developed for visualized uracil-DNA glycosylase (UDG) activity assay using gold nanoparticles (AuNPs). This strategy relies on the enzyme-catalyzed assembly of AuNPs decorated with DNA probes. In the presence of endonuclease...
As a greedy search algorithm, classification and regression tree (CART) is easily relapsing into overfitting while modeling microarray gene expression data. A straightforward solution is to filter irrelevant genes via identifying significant ones. Considering some significant genes with multi-modal expression patterns exhibiting systematic difference in within-class samples are difficult to be identified...
A novel strategy that combines the second-order calibration method based on the trilinear decomposition algorithms with high performance liquid chromatography with diode array detector (HPLC-DAD) was developed to mathematically separate the overlapped peaks and to quantify quinolones in honey samples. The HPLC-DAD data were obtained within a short time in isocratic mode. The developed method could...
A rapid non-separative spectrofluorometric method based on the second-order calibration of excitation–emission matrix (EEM) fluorescence was proposed for the determination of napropamide (NAP) in soil, river sediment, and wastewater as well as river water samples. With 0.10molL −1 sodium citrate–hydrochloric acid (HCl) buffer solution of pH 2.2, the system of NAP has a large increase in fluorescence...
A highly sensitive electrochemical immunosensor based on combination of chitosan (CHIT) and coral-shaped AuNPs (C-AuNPs) to form an immobilization matrix has been developed using human IgG as a model analyte. The inorganic–organic hybrid film with abundant adsorbing sites and large surface area can reserve the biocompatibility of the biomaterials which greatly increase loading amounts of assembling,...
Representing a compound by a numerous structural descriptors becomes common in quantitative structure–activity relationship (QSAR) studies. As every descriptor carries molecular structure information more or less, it seems more advisable to investigate all the possible descriptor vectors rather than traditional variable selection when building a QSAR model. Based on particle swarm optimization (PSO)...
Set the date range to filter the displayed results. You can set a starting date, ending date or both. You can enter the dates manually or choose them from the calendar.