查看更多>>摘要:As one of the most common and important post-translational modifications, protein N-glycosylation plays essential roles in many biological processes and have long been considered closely correlated with the occurrence and progression of multiple diseases. Systematic characterization of these disease-related protein N-glycosylation is one of the most convenient ways for new diagnostic biomarker and therapeutic drug target discovering. However, the biological samples are extremely complex and the abundance of N-glycoproteins are especially low, which make highly efficient N-glycoprotein/glycopeptide enrichment before mass spectrometry analysis a prerequisite. In this work, a new type of hydrophilic material (GO-pDMAPS) was prepared by in situ growth of linear zwitterionic polymer chains on the surface of GO and it was successfully applied for N-glycopeptide enrichment from human urine. Due to the excellent hydrophilicity and the facilitate interactions between this GO-pDMAPS and the targets, a total of 1426 N-glycosylated sites corresponding to 766 N-glycoproteins as well as 790 N-glycosylation sites corresponding to 470 N-glycoproteins were enriched and identified from urine of healthy subjects and patients with lung adenocarcinoma, respectively. Among which, 27 N-glycoproteins were expressed exclusively and 4 N-glycoproteins were upregulated at least 3 times comparing with the healthy group, demonstrating the tremendous potential of this new hydrophilic material for large scale and in depth N-glycoproteome research.
查看更多>>摘要:As a popular controllable-released carrier, intelligent hydrogels are often used in drug delivery and disease therapeutics. Meanwhile, benefit from the mimic-enzyme activity performance, Fe-N-C nanozymes have been widely used in sensing and analysis. However, the combination of intelligent hydrogels with specific degradability and Fe-N-C nanozymes with enhanced activity in one system to achieve controllable and sensitive detection is rare. Herein, we combine intelligent hydrogel with mimic peroxidase activity enhanced Fe-N-C nanozymes to construct a ratiometric fluorescence probe for sensitive detection of hyaluronidase (HAase). The modification of copper ions has been proved to enhance the mimic enzyme activity of Fe-N-C nanozymes greatly. Cu2+ modified Fe-N-C nanozymes were embedded in hyaluronic acid hydrogel. In the presence of HAase, the HA hydrogel structure was hydrolyzed and released Cu2+-Fe-N-C nanozymes gradually. The released Cu2+-Fe-N-C nanozymes are used to catalyze the hydrogen peroxide system so that o-phenylenediamine is oxidized to orange fluorescent 2, 3-diaminophenolazine (DAP). Due to the electrostatic interaction, the fluorescence resonance energy transfer can occur between the negatively charged copper nanoclusters emitted by 430 nm and the positively charged DAP emitted by 560 nm. The activity of HAase was monitored according to the ratio of fluorescence intensity at 560 nm and 430 nm (F560/F430). The linear range of this method is 0-10.0 U/ml and the detection limit is 0.43 U/mL (S/N = 3). This strategy has been further applied to biological samples successfully.
查看更多>>摘要:A highly sensitive cationic polyfluorinated azobenzene/reduced graphene oxide (C3F7-azo(+)/RGO) nano composite electrochemical sensor for simultaneous detection of dopamine (DA), ascorbic acid (AA) and uric acid (UA) was successfully synthesized using a facile exfoliation/restacking method. The nanocomposite is self assembled from oppositely charged graphene oxide nanosheets (GO) and polyfluorinated azobenzene cations (C3F7-azo(+)), and then obtained by electrochemical reduction. The structure and electrochemical properties were characterized by X-ray diffraction (XRD), energy dispersive spectrometer analysis (EDS), transmission electron microscope (TEM) and scanning electron microscope (SEM). The electrochemical property of C3F7-azo(+)/RGO was characterized by cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), and differential pulse voltammetry (DPV). It can be clearly seen from experimental results that C3F7-azo(+)/RGO-modified electrode (C3F7-azo(+)/RGO/GCE) can detect DA, AA and UA simultaneously, and has good stability and anti interference performance. The detection limits are 65 nM, 8 nM and 11 nM for DA, AA and UA in the ranges 57.28-134.28 mu M, 0.04-6.01 mu M, 9.23-23.45 mu M, respectively.
John, Anto J. U. K.Elkington, PaulEason, Robert W.Sones, Collin L....
8页
查看更多>>摘要:Inflammatory markers including C-reactive protein (CRP) and procalcitonin (PCT) have been shown to be useful biomarkers to improve triage speed and prevent the inappropriate use of antibiotics for infections such as pneumonia. Here, we present a novel and exciting solution to guide the administration of antibiotic treatment via rapid, semi-quantitative and multiplexed detection of CRP and PCT using an advanced lateral flow device (LFD) designed to have multiple parallel flow-paths, produced via the precise laser-based partitioning of the single flow-path of a standard LFD. Each flow-path within this multiplexed LFD has a unique detection capability which permits tailored detection of CRP within a predefined cut-off range (20 mu g/mL -100 mu g/mL) and PCT above a pre-defined threshold (0.5 ng/mL). We demonstrate the use of this LFD in the successful detection of CRP and PCT semi-quantitatively within spiked human serum samples. This multiplexed near-patient assay has potential for development into a rapid triage and treatment of patients with suspected pneumonia.
查看更多>>摘要:Paper-based biosensor is one of the most commonly used platforms for point-of-care testing (POCT). Among these platforms, microfluidic paper-based analytical devices (mu PADs) have the most versatile designs due to the different hydrophobic barrier patterns and layers of the devices. In addition, mu PADs can also be used in com-bination with other biosensor platforms to improve the performance of the device. Simple and convenient methods for fabricating low-cost and design-adjustable hydrophobic barriers on paper are one of the most challenging aspects for creating mu PADs. This work demonstrated a simple technique for using the common polylactic acid (PLA) filament and wax filament to create hydrophobic barriers on paper for mu PADs using a commercialized 3D printer. As a proof of concept, the papers with 3D printed PLA barrier were used in com-bination with a fluidic chip in a prototype biosensor, in which the barrier paper housed four cell-free reactions and the fluidic chip achieved sample delivery to the reactions in the device. Our designed prototype was capable of discriminating dengue virus serotypes based on small nucleotide sequence differences. The proposed com-bination of 3D-printed barrier paper and fluidic chip provides a versatile platform for rapid prototyping of POCT with possible compatibility with various detection systems.
查看更多>>摘要:A facile, universal and highly efficient approach for producing a self-cleaning electrochemical protein-imprinting biosensor based on dual stimuli-responsive memory hydrogels via free-radical polymerisation is described. As confirmed by static contact angle and scanning electron microscopy results, the imprinted hydrogels exhibited reversible conformational changes after being simulated by an external electric field and temperature. By exploring the properties of imprinted hydrogels for sensing applications, the electrochemical protein-imprinting biosensor was originally fabricated on a glassy carbon electrode using the drop-casting method. Because of the trigger gates of the temperature and electric field, the biosensor demonstrated excellent self-cleaning behaviours compared with other corresponding electric-field or thermo-responsive imprinting biosensors. Moreover, the prepared biosensor exhibited satisfactory selectivity, good biocompatibility, comparable limits of detection and linearity ranges as well as acceptable stability toward bovine serum albumin. Consequently, the biosensor was successfully employed to simultaneously enrich, detect and extract bovine serum albumin from complex bio-logical samples; the process was dynamic, controllable and harmless to the template under the dual external stimuli. Thus, the proposed biosensor exhibited considerable potential in controlled drug/chemical delivery and smart sensing for bioanalyses involving dual stimuli-responsive behaviours.