Accurate determination of dopamine (DA) and uric acid (UA) in biological samples is crucial in diagnosing neurodegenerative disorders and gout, respectively. Here we report a highly sensitive and inexpensive, flexible screen-printed sensor for determining DA and UA in sweat samples. Beta-cyclodextrin-based (βCD) composite gel with reduced graphene oxide (rGO) was synthesized by self-polymerization of βCD at an optimum ratio of "good" and "poor solvent".
View Article and Find Full Text PDFWhite spot syndrome virus (WSSV) is a significant threat to the aquaculture sector, causing mortality among crabs and shrimps. Currently available diagnostic tests for WSSV are not rapid or cost-effective, and a new detection method is therefore needed. This study demonstrates the development of a biosensor by functionalization of magnetosomes with VP28-specific antibodies to detect WSSV in seafood.
View Article and Find Full Text PDFAlthough the recent advancement in wearable biosensors provides continuous, noninvasive assessment of physiologically relevant chemical markers from human sweat, several bottlenecks still exist for its practical use. There were challenges in developing a multiplexed biosensing system with rapid microfluidic sampling and transport properties, as well as its integration with a portable potentiostat for improved interference-free data collection. Here, we introduce a clean-room free fabrication of wearable microfluidic sensors, using a screen-printed carbon master, for the electrochemical monitoring of sweat biomarkers during exercise activities.
View Article and Find Full Text PDFListeriosis through contaminated food is one of the leading causes of premature deaths in pregnant women and new born babies. Here, the authors have developed a magnetosomes-based biosensor for the rapid, sensitive, specific and cost-effective detection of from food sample. Magnetosomes were extracted from RJS1 and then directly bound to anti-Listeriolysin antibody (0.
View Article and Find Full Text PDFMater Sci Eng C Mater Biol Appl
September 2020
Epidemic Salmonellosis contracted through the consumption of contaminated food substances is a global concern. Thus, simple and effective diagnostic methods are needed. Magnetosome-based biosensors are gaining attention because of their promising features.
View Article and Find Full Text PDFA method for the amperometric determination of Myo-inositol is presented. Nanostructured copper sulfide material was synthesized by solvothermal method and utilized as sensor matrix. The physico-chemical analysis using XRD, Raman, FE-SEM, TEM, and XPS confirmed the formation of CuS material.
View Article and Find Full Text PDFColloids Surf B Biointerfaces
October 2018
In this work, we report a methodology for the quantification of Homocysteine (HcySH) at neutral pH (pH-7.0) using Au nanoparticles incorporated reduced graphene oxide (AuNP/rGO/GCE) modified glassy carbon electrode. The modified electrode was characterized using SEM and XRD techniques.
View Article and Find Full Text PDFMater Sci Eng C Mater Biol Appl
December 2016
Herein, we report a simple, facile and reproducible non-enzymatic hydrogen peroxide (H2O2) sensor using electrochemically reduced graphene oxide (ERGO) modified glassy carbon electrode (GCE). The modified electrode was characterized by Fourier transform infrared (FT-IR), UV-Visible, scanning electron microscopy (SEM) and atomic force microscopy (AFM) techniques. Cyclic voltammetric (CV) analysis revealed that ERGO/GCE exhibited virtuous charge transfer properties for a standard redox systems and showed excellent performance towards electroreduction of H2O2.
View Article and Find Full Text PDFWe report a novel seedless Hg(2+)-induced synthetic approach for the preparation of gold nanostructures. This protocol is demonstrated for the highly selective and sensitive naked eye detection of Hg(2+) based on the high affinity metallophilic Hg(2+)-Au(+) interaction. The response time upon exposure to Hg(2+) is almost instantaneous.
View Article and Find Full Text PDFPt colloid and Pt-Pd colloid, pristine polyaniline, polyaniline/Pt nanocomposite and polyaniline/Pt-Pd nanocomposite were synthesized by simple chemical method. They were characterized by UV-Vis, FT-IR, XRD, TGA, SEM, HR-SEM and HR-TEM with EDAX techniques. The results proved that there is a strong interaction between metal nanoparticles (Pt-Pd) and polyaniline chains.
View Article and Find Full Text PDFThis article describes the investigation of direct electron transfer (DET) between glucose oxidase (GOD) and the electrode materials in an enzyme-catalyzed reaction for the development of improved bioelectrocatalytic system. The GOD pedestal electrochemical reaction takes place by means of DET in a tailored Vulcan carbon paste electrode surfaces with GOD and chitosan (CS), allowing efficient electron transfer between the electrode and enzyme. The key understanding of the stability, biocatalytic activity, selectivity, and redox properties of these enzyme-based glucose biosensors is studied without using any reagents, and the properties are characterized using electrochemical techniques like cyclic voltammogram, amperometry, and electrochemical impedance spectroscopy.
View Article and Find Full Text PDFIn this work, the determination of cadmium has been attempted using an indium film electrode in the presence of bromide ions as an additive, for the first time. The electrode was prepared in situ on a glassy carbon substrate and employed in combination with square wave anodic stripping voltammetry. The purpose of having bromide ions is to enhance the analytical value of cadmium detection.
View Article and Find Full Text PDFColloids Surf B Biointerfaces
March 2013
Polyaniline, polyaniline/Ag-Pt nanocomposite and bimetal (Ag-Pt) colloidal solution were chemically synthesized and characterized by UV-vis, XRD, FT-IR, TGA, HRSEM with EDAX and HRTEM techniques. The results reveal that there was a strong interaction between Ag-Pt nanocomposite and polyaniline chains. This interaction makes only small changes in the backbone chain of polyaniline/Ag-Pt nanocomposite when compared with polyaniline.
View Article and Find Full Text PDFHerein, we report a one-pot synthesis of highly stable Au nanoparticles (AuNPs) using 3,4-ethylenedioxythiophene (EDOT) as a reductant and polystyrene sulfonate (PSS-) as a dopant for PEDOT and particle stabilizer. The synthesis demonstrated in this work entails the reduction of HAuCl4 using EDOT in the presence of PSS-. The formation of AuNPs with concomitant EDOT oxidation is followed by UV-vis spectroscopy at various time intervals.
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