A rapid magnetic particle-based enzyme immunoassay for human cytomegalovirus glycoprotein B quantification

Abstract Human cytomegalovirus (HCMV) is a herpes virus that can cause severe infections. Still, the available methods for its diagnostic have the main disadvantage of requiring long time to be performed. In this work, a simple magnetic particle-based enzyme immunoassay (mpEIA) for the quantification of glycoprotein B of Human cytomegalovirus (gB-HCMV) in urine samples is proposed. The immunosensor scheme is based on the analyte protein gB-HCMV sandwiched between a primary monoclonal antibody, (MBs-PrG-mAb1), and a secondary anti-gB-HCMV antibody labelled with Horseradish peroxidase (Ab2-HRP) to allow spectrophotometric detection. The mpEIA analytical performance was tested in urine samples, showing a linear dependence between gB-HCMV concentration and the absorbance signal at 450 nm in a range of concentrations from 90 to 700 pg mL −1 . The calculated detection limits for gB-HCMV were 90 ± 2 pg mL −1 and the RSD was about 6.7% in urine samples. The immunosensor showed good selectivity against other viruses from Herpesviridae family, namely varicella zoster and Epstein Barr viruses. The recoveries of spiked human urine samples at 0.30–0.50 ng mL −1 concentration levels of gB-HCMV ranged between 91 to 105%. The proposed mpEIA method was validated following the guidelines of the European Medicines Agency (EMEA-2014), and allows rapid, successful and easy quantification of gB-HCMV in urine samples.