Label-Free Impedimetric Nanoband Sensor for Detection of Both Bovine Viral Diarrhoea Virus (BVDV) and Antibody (BVDAb) in Serum
In veterinary medicine, diagnostic tools enabling early detection of infectious disease in cattle could play a pivotal role in the control and eradication of bovine viral diarrhoea (BVD). Early identification of cattle persistently infected with bovine viral diarrhoea virus (BVDV) is critical for early diagnosis and isolation of the animal from a susceptible herd. The immediate availability of electronic test results to a veterinarian on-farm, would eliminate the need to submit samples to a commercial laboratory thereby improving animal therapeutic outcomes considerably. An impedimetric silicon chip-based biosensor platform, containing six gold nanoband electrodes as six individual sensors, was developed in this study for detection of BVD disease target molecules. Gold nanoband electrodes were first coated with an electrodeposited polymer and then modified with either monoclonal antibodies or Erns protein, for the subsequent detection of BVD virus and antibodies in whole serum, respectively. We demonstrate that the nanoband sensors have sufficient sensitivity and specificity for serological detection of both targets, with a low time-to-result (20 minutes). All serological samples were benchmarked against, and in complete agreement with, gold standard commercial ELISA methods. These initial proof-of-concept findings are of particular significance for potential on-farm point of use applications, where rapid analysis times and specificity are required to permit early diagnostics by veterinarians.