A silver-palladium alloy nanoparticle-based electrochemical biosensor for simultaneous detection of ractopamine, clenbuterol and salbutamol

A multiplexed electrochemical biosensor has been developed for fast and sensitive detection of ractopamine (RAC), salbutamol (SAL) and clenbuterol (CLB) based on reduced graphene oxide (rGO) and silver-palladium alloy nanoparticles (AgPd NPs). In this paper, rGO with high conductivity was used as an electrode material to immobilize artificial antigens and amplify electrochemical signal. AgPd NPs are used to label antibodies and generate a strong electrochemical signal in phosphate buffered saline (PBS) without any other substrates. Screen-printed carbon electrode (SPCE) and competition strategy were adopted to achieve simultaneous detection of RAC, SAL and CLB without cross-talk between adjacent electrodes. This method can simultaneously detect RAC, SAL and CLB ranging from 0.01 to 100 ng mL(-1) with detection limits of 1.52 pg mL(-1), 1.44 pg mL(-1) and 1.38 pg mL(-1), respectively. Satisfactory results are achieved in pork sample analysis. The designed strategy provides a promising potential in determination of other biological samples. (C) 2013 Elsevier B.V. All rights reserved.