Renewable amperometric immunosensor based on paraffin–graphite–transferrin antiserum biocomposite for transferrin assay

Abstract

A renewable electrochemical immunosensor was developed for the determination of transferrin in human serum. It is based on a paraffin-graphite-transferrin antiserum biocomposite, which needs no additional curing. A competitive binding assay was used to determine transferrin in human serum with the aid of transferrin labeled with horseradish peroxidase. The assay conditions were optimized, including the loading of transferrin antiserum in the biocomposite, the amount of labeled transferrin in the incubation solution, incubation time and temperature. Serum samples were analyzed and the results demonstrate that the concentration range of determination with this system meets the demands of clinical analysis. The surface of the immunosensor can be regenerated by simply polishing to obtain a fresh immunocomposite ready to be used in a new competitive assay.

Silica Sol-gel Amperometric Immunosensor for Schistosoma Japonicum Antibody Assay

“…12 The methodology employed in the preparation of silica sol-gel was similar to the one reported by Pankaratov and Lev. 22 Sol-gel was obtained by mixing 0.8 ml of tetramethoxysilane, 0.5 ml of ethanol, 0.5 ml of water and 0.2 ml of 0.01 M HCl.…”

“…In an incubation procedure of competitive binding immunoassay, 12 the SjAb from the analytical sample and the HRP-SjAb added would compete binding on the electrode surface. The amount of HRP-SjAb bound on the electrode surface after incubation would be reversibly proportional to the amount of SjAb in the analytical sample.…”

“…A key step in developing a biosensor is the immobilization of the sensing agent. 9 Methacrylate, 10 epoxy, 11 and paraffin 12 have been used as the matrix material to prepare an immunosensor. These materials used for immobilization were mostly organic polymers.…”

Sensitive Electrochemical Detection of Horseradish Peroxidase at Disposable Screen‐Printed Carbon Electrode

“…It is frequently used as secondary detection reagents ( i.e. label) in numerous biotechnological applications, including immunohistochemical analysis [1] and enzyme-linked immunosorbent assays (ELISAs) [2], in-situ hybridization [3], blot analysis [4], immuno [5-7] and DNA biosensors [8]. …”

“…The 3-APZ could undergo a reversible redox reaction (Scheme 2) [28]. Among various techniques used in electrochemical analysis, amperometric method was studied extensively to measure the electrocatalytic current generated by the HRP enzymatic reaction [5-7, 20, 22, 23, Error! Reference source not found.…”