A self-contained fiber-optic immunosensor was developed to measure the 16,500-Da protein myoglobin. The sensing element was constructed by entrapment of Cascade Blue-labeled antibody within polyacrylamide gel at the distal face of an optical fiber 300 microns in core diameter. The polyacrylamide gel composition was optimized to allow diffusion of myoglobin but to exclude hemoglobin and higher-m...

Monoclonal antibodies with specificity against the Francisella tularensis outer lipopolysaccharide (LPS) membrane were prepared and characterized using the piezoelectric immunosensor with immobilized LPS antigen from F. tularensis. Signals obtained by the immunosensor were compared with ELISA and similar sensitivity was noticed. Signal of negative controls obtained using the biosensor was below...

In this work, a novel amperometric immunosensor based on multi-walled carbon nanotubes-thionine-chitosan (MWCNTs-THI-CHIT) nanocomposite film as electrode modified material was developed for the detection of chlorpyrifos residues. The nanocomposite film was dropped onto a glassy carbon electrode (GCE), and then the anti-chlorpyrifos monoclonal antibody was covalently immobilized onto the surfac...

An ultrasensitive electrochemical immunosensor for the detection of tumor marker human chorionic gonadotropin (hCG) was developed with a limit of detection as low as 2 pg mL-1 in phosphate buffer. The Platinum nanoparticles (PtNPs) were electrodeposited to modify the gold surface and to increase enlarging the electrochemically active sites, resulting in the facilitation of electron exchange. Cy...

A portable evanescent wave optic fiber immunosensor was developed for detection of 2,4-dichlorophenoxyacetic acid(2,4-D) using a indirect competitive immunoassay. In this paper, hapten conjugates 2,4-D-OVA were immobilized with covalent binding methods. After pre-reacting, 2,4-D-antibody-Cy5.5 in sample specifically recognized the 2,4-D antigens binding sites on surface of the optical fiber pro...

The first electrochemical immunosensor for the determination of fibroblast growth factor receptor 4 (FGFR4) biomarker is reported in this work. The biosensor involves a sandwich configuration with covalent immobilization of a specific capture antibody onto activated carboxylic-modified magnetic microcarriers (HOOC-MBs) and amperometric detection at disposable carbon screen-printed electrodes (S...

In this study, we have developed a label-free immunosensor with the variation of resonance frequency (Δf) of a quartz crystal microbalance (QCM) as readout signal for ultrasensitive detection of Ketamine (KT). An optimized strategy for immobilization of KT antibody on the surface of the QCM chip was implemented via the self-assembly modification of 3-mercaptopropionic acid, and then activated w...

In this work, we fabricated a novel photoelectrochemical immunosensor for assay of DNA methylation, where Bi2S3 nanorods were used as photoelectric conversion material, MBD1 protein (a kind of methyl bonding domain protein) was used as DNA methylation recognizing unit, anti-his tag antibody was used to further inhibit the photocurrent and increase the detection sensitivity. The results demonstr...

This study describes a new strategy toward the development of advanced immunosensors based on chemically functionalized magnetic-core/porous-shell CoFe2O4/Cu2O composite nanoparticles, and the preparation, characterization, and measurement of relevant properties of the immunosensor useful for the detection of hepatitis B surface antigen (HBsAg) in clinical immunoassay. The immunosensor based on...