Flow injection immunosensing of polycyclic aromatic hydrocarbons with a quartz crystal microbalance

A piezoelectric immunosensor has been developed for the detection of variou s polycyclic aromatic hydrocarbons (PAHs). The antigen (benzo[a]pyrene-BSA conjugate, BaP-BSA) was immobilized through thioctic acid on gold coated qu artz crystals, with a basic resonant frequency of 10 MHz. The monoclonal an tibody 10c10 (mAb10c10), which specifically recognizes benzo[a]pyrene (BaP) , was detected through frequency decreases (mass increase due to the immuno reaction). Determination of BaP was performed in the flow injection system by using a competitive pattern, in which BaP reacted with the bound mAb10c1 0 causing frequency increases. A nanomolar level of BaP can be detected wit h this immunosensor. The mAb10c10 modified quartz crystal cross-reacts with pyrene and naphthalene. (C) 1999 Elsevier Science B.V. All rights reserved .