Detection of the cancer-associated T antigen using an Arachis hypogaea agglutinin biosensor

Publication date: Available online 5 June 2019Source: Biosensors and BioelectronicsAuthor(s): MaríaG.H. Rangel, M. Luísa S. SilvaAbstractAn impedimetric biosensor was developed for the selective detection of the cancer-associated T antigen, using the lectin from Arachis hypogaea (peanut agglutinin, PNA) as the recognition element. The increase in the biosensor's impedance after sample incubation was indicative of lectin recognition and complex formation between PNA and glycoproteins containing T antigen. When using asialofetuin as model glycoprotein, a minimum amount of 100 ng of glycoprotein could be detected, generating an increase in impedance of 7.2%. Albumin did not cause interference in the detection of T-carrying glycoproteins up to a concentration of 0.01 mg ml−1.The biosensor was used to evaluate the T-antigen expression in serum samples and was able to discriminate between control samples (of individuals without cancer) and case samples from patients with diverse types of carcinomas (skin, colon, breast, prostate, stomach, kidney, lung, liver and rectum) in which an increase in the expression of T antigen is well-known. The same samples were analyzed with a Vicia villosa agglutinin biosensor that has specificity for the cancer-associated Tn antigen, to compare the expression of both antigens in the diverse carcinomas. The results were different for both biosensors, confirming that the use of different lectins allows to monitor different antigen expression....
Source: Biosensors and Bioelectronics - Category: Biotechnology Source Type: research