Novel surface coatings for antibody attachment to surface plasmon resonance sensors

Abstract

Multiple layers were attached to the gold surface of surface plasmon resonance (SPR) sensor to maximize the antibody loading and the specific signal of an antigen, while minimizing non-specific signal from full serum proteins. A three-fold improvement of the specific signal from myoglobin and a three-fold decrease of non-specific signal from serum were observed using the N-hydroxysuccinimide ester of 16-mercaptohexadecanoic acid (NHS-MHA) compared to the currently commercially available carboxymethylated dextran. Self-assembled monolayers were attached to the gold surface. 2-mercaptoacetic acid, 3-mercaptopropionic acid, 4,4'-dithiodibutyric acid, 11-mercaptoundecanoic acid, and 16-mercaptohexadecanoic acid were investigated. The covalent attachment of the layers was monitored using SPR and GATR-FTIR. Antibodies to human myoglobin were covalently attached to the sensor using EDC / NHS chemistry and detection of 25 ng/mL myoglobin solution was monitored for the specific signal. Exposing the sensors with the layers to full bovine serum, protein concentration of 72 mg/mL, monitored non-specific signal. NHS-MHA was used to quantify proteins cell culture media with limits of detection below 1 ng/mL.