Optical Fiber Immunosensor Based on a Poly(pyrrole−benzophenone) Film for the Detection of Antibodies to Viral Antigen

Abstract

We describe herein a newly developed optical microbiosensor for the diagnosis of hepatitis C virus (HCV) by using a novel photoimmobilization methodology based on a photoactivable electrogenerated polymer film deposited upon surface-conductive fiber optics, which are then used to link a biological receptor to the fiber tip through light mediation. This fiber-optic electroconductive surface modification is done by the deposition of a thin layer of indium tin oxide on the silica surface of the fiber optics. Monomers are then electropolymerized onto the conductive metal oxide surface; thereafter, the fibers are immersed in a solution containing HCV-E2 envelope protein antigen and illuminated with UV light (wavelength approximately 345 nm). As a result of the photochemical reaction, a thin layer of the antigen becomes covalently bound to the benzophenone-modified surface. The photochemically modified fiber optics were tested as immunosensors for the detection of anti-E2 protein antibody analyte that was measured through chemiluminescence reaction. The biosensor was tested for sensitivity, specificity, and overall practicality. Our results suggest that the detection of anti-E2 antibodies with this microbiosensor may enhance significantly HCV serological standard testing especially among patients during dialysis, which were diagnosed as HCV negative, by standard immunological tests, but were known to carry the virus. If transformed into an easy to use procedure, this assay might be used in the future as an important clinical tool for HCV screening in blood banks.

Chemiluminescence Platforms in Immunoassay and DNA Analyses

“…The photochemically modified fiber optics was tested as an immunosensor for the detection of the anti-E2 protein antibody. 37 In addition, the inactivated Ebola virus was immobilized to the tip of an optical fiber by using a photoelectrochemical method. 38 Finally, by using the HPR-H2O2-luminol CL reaction, the fiber-optic immunosensor could sensitively detect a low titer of 1:960000 and 1:1000000 for subtypes in Zaire and Sudan, respectively.…”

A localized surface plasmon resonance based immunosensor for the detection of casein in milk

“…For the optimization of anti-casein antibody concentrations, the absorbance intensity increments of LSPR signals were measured in a series of anti-casein antibody dilutions (3,5,10,20,40, and 60 mg/mL) using 100 mg/mL of target casein. As shown in Fig.…”

“…Optical [2][3][4], piezoelectric [5], and electrochemical [6,7] immunosensors in connection with microfluidic systems [8] have successfully been applied to monitor antigen-antibody binding reactions. In recent years, immunosensors based on surface plasmon resonance (SPR) were developed for the measurement of antigens, which could bind to antibodies immobilized on the biosensor surface [9][10][11].…”

Local detection of enzymatic ion generation with polycrystalline silicon interdigitated electrodes and its application to biosensing

“…Enzymes are one of the most commonly used labels in biosensing. They can be easily conjugated to biomolecules via different cross linkers and well known chemical procedures, and the reactions they catalyze can be detected either optically 6,7 or electrochemically. [8][9][10][11] In this letter, a biosensing principle is presented and tested.…”