Developing immunosensing platforms capable of simultaneously detecting multiple cancer markers is crucial for clinical diagnosis and biomedical research. Here, we introduce a novel dual-mode electrochemical biosensing assay platform capable of detecting two gastric cancer biomarkers: pepsinogen I (PG I) and pepsinogen II (PG II). Methylene blue (MB) and Prussian blue (PB) were used as dual signal sources to label PG I and PG II, respectively.
View Article and Find Full Text PDFGastric cancer (GC) is a common malignant tumour of the digestive tract with a high mortality rate worldwide. However, many patients delay treatment due to the avoidance of the costly and painful procedure of gastroscopy. Therefore, an early convenient screening method is essential to improve the survival rate of GC patients.
View Article and Find Full Text PDFBackground: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is a highly infectious and concealed virus that causes pneumonia, severe acute respiratory syndrome, and even death. Although the epidemic has been controlled since the development of vaccines and quarantine measures, many people are still infected, particularly in third-world countries. Several methods have been developed for detection of SARS-CoV-2, but owing to its price and efficiency, the immune strip could be a better method for the third-world countries.
View Article and Find Full Text PDFUsing gold and magnetic nanoparticles co-decorated reduced graphene oxide-tetraethylenepentamine (rGO-TEPA/Au-MNPs) as the magnetic platform for capturing the primary antibody (Ab), separation and preconcentration of immunocomplex, a novel homogeneous electrochemical immunosensor was successfully developed. The newly prepared magnetic rGO-TEPA/Au-MNPs, compared with MNPs, exhibited better stability and enhanced electrical conductivity attributed to rGO-TEPA, and showed higher biorecognition efficiency due to AuNPs. In addition, Au@PtNPs were prepared and modified with secondary antibody (Ab) as an efficient signal probe for signal readout.
View Article and Find Full Text PDFIn this article, a highly sensitive label-free immunosensor based on a graphene oxide (GO)/FeO/Prussian blue (PB) nanocomposite modified electrode was developed for the determination of human hepatitis B surface antigen (HBsAg). In this electrochemical immunoassay system, PB was used as a redox probe, while GO/FeO/PB nanocomposites and AuNPs were prepared and coated on screen-printed electrodes to enhance the detection sensitivity and to immobilize the hepatitis B surface antibody (HBsAb). The immunosensor was fabricated based on the principle that the decrease in peak currents of PB is proportional to the concentration of HBsAg captured on the modified immunosensor.
View Article and Find Full Text PDFA novel 3D paper-based microfluidic screen-printed electrode (SPE) composed of two layers was constructed by photolithography and screen-printing technology. Aldehyde functionalized hydrophilic zone of the counter and reference electrodes layer was prepared for glucose oxidase immobilization. Highly conductive prussian blue deposited reduced graphene oxide-tetraethylene pentamine (rGO-TEPA/PB) modified paper working electrode layer can be used as an electrochemical sensitive membrane for quantitative detection of hydrogen peroxide (HO), which was the enzyme-catalyzed reaction product.
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