A novel immunoassay for residual bovine serum albumin (BSA) in vaccines using laser-induced fluorescence millimeter sensor array detection platform

A highly sensitive and stable sandwich fluorescence immunoassay for the quantitative detection of residual BSA in vaccines based on the labels of the functionalized fluorescent core-shell silica nanoparticles and laser-induced fluorescence millimeter sensor array detection platform has been developed. On a glass slide with low fluorescence background, capture antibody against BSA was immobilized, after BSA was captured, another identify antibody against BSA which was labeled with the new fluorescent silica nanoparticles was used to recognize the BSA. The fluorescence issued from the fluorescent silica nanoparticles was successfully detected by the laser induced fluorescence millimeter sensor assay detection platform which was made by us. This method exhibited high performance with a linear correlation between response and amount of BSA in the range 1.0–100 ng/mL and the detection limit was 0.3 ng/mL (3σ). The relative standard deviation (R.S.D.) was 6.7% at the concentration of 20 ng/mL for 5 parallel measurements of BSA.