Background: Developing functional foods by utilizing plants can often lead to compromised sensory properties. Thus this study investigates the combination of plants to produce synergistic effects and to incorporate these plant powders into a pasta formulation without affecting its sensory acceptance. Six common Brunei medicinal plants were evaluated for their in vitro antioxidant activity determined by 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity (IC ), ferric reducing antioxidant power (FRAP) assay and 2,2'-azino-bis(3-ethylbenziazoline-6-sulfonic acid) (ABTS) radical scavenging assay.
View Article and Find Full Text PDFThis work reports on the first electrochemiluminescence (ECL) immunosensor employing a novel nanostructured composite of titanium dioxide (TiO) and gold nanourchins (AuNU) to detect protein allergen Ovomucoid (Ovm) found in eggs. TiO and AuNU were dispersed in Nafion and drop-casted onto SPGE with Tris(2,2'-bipyridyl)-ruthenium (II) ([Ru(bpy)]) and tri-n-propylamine (TPrA) served as strong luminophore/co-reactant pairs as a source of ECL signals. The linear range, limit of detection, reproducibility and practical applications of the sensor were assessed.
View Article and Find Full Text PDFBiosensor technology is experiencing an unprecedented momentum that is driven by rapid advances in material science for utilization in various fields, and is constantly evolving to develop fast, simple and sensitive sensors. Here, we present a comprehensive and concise review on electrochemiluminescent (ECL) nanomaterial-based aptasensors including challenges and applications. ECL aptasensor combines the merits of a biosensor, selectivity of an aptamer, and sensitivity of ECL to construct sensitive and selective sensors.
View Article and Find Full Text PDFIn this study, a direct and label-free immunosensor was designed and constructed by modifying the screen-printed electrode with graphene nanoplatelets (GNPs) for the detection of the cardiac troponin T (cTnT). Firstly, GNPs were drop-casted onto carbon working electrode. Monoclonal cTnT antibodies were then immobilized on the GNPs via physical adsorption; finally, BSA was introduced to block non-specific binding sites.
View Article and Find Full Text PDFIn this work, a nanocomposite of gold nanoparticles (AuNPs), carbon nano-onions (CNOs), single-walled carbon nanotubes (SWCNTs) and chitosan (CS) (AuNPs/CNOs/SWCNTs/CS) was prepared for the development of highly sensitive electrochemical immunosensor for the detection of carcinoembryonic antigen (CEA), clinical tumor marker. Firstly, layer-by-layer fabrication of the CEA-immunosensors was studied using cyclic voltammetry (CV) and square wave voltammetry (SWV). By combining the advantages of large surface area and electronic properties of AuNPs, CNOs, SWCNTs, and film forming properties of CS, AuNPs/CNOs/SWCNTs/CS-nanocomposite-modified glassy carbon electrode showed a 200% increase in effective surface area and electronic conductivity.
View Article and Find Full Text PDFRecently, there has been a growing concern of consumers on the authenticity of food ingredients including adulteration with porcine and/or its derivatives. Therefore, this work reports on the development of a novel, simple, sensitive and rapid luminol-based electrochemiluminescence (ECL) technique for Sus scrofa (Porcine) DNA detection. Porcine DNA was firstly amplified using loop-mediated isothermal amplification (LAMP) method and subsequently added to luminol solution for further ECL analysis for quantification.
View Article and Find Full Text PDFA label free electrochemical immunosensor for sensitive detection of porcine serum albumin (PSA) is reported in this work. The immunosensor was constructed by first electrochemically reducing 4-carboxyphenyl diazonium salt, which had been electrochemically generated in situ, to a stable 4-carboxyphenyl layer on carbon nanofiber-modified screen printed electrode. Antibodies were covalently attached onto the electrode using carbodiimide chemistry between the carboxylic groups of the 4-carboxyphenyl layer and amine groups of the antibody.
View Article and Find Full Text PDFA carbon nanofiber-based label free electrochemical immunosensor for sensitive detection of recombinant bovine somatotropin (rbST) was developed. In this immunosensor design, a mild site-directed antibody immobilization via interaction of boronic acid and oligosaccharide moiety found on Fc region of an antibody was performed to preserve the biological activity of antibody and improve the sensor's sensitivity. Electrochemical characterization of the immunosensor fabrication was carried out by differential pulse voltammetry (DPV) in Fe(CN)6(3-)/Fe(CN)6(4-) probe.
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