Rapid high-throughput detection of diethylstilbestrol by using the arrayed langasite crystal microbalance combined with gold nanoparticles through competitive immunoassay

In this paper, a method for the rapid detection of diethylstilbestrol (DES) using quartz crystal microbalance (QCM) with gold nanoparticles (AuNPs) amplification was developed and this method was used on the arrayed langasite crystal microbalance (LCM) to realize the high-throughput detection of DES. A sensitive membrane which can recognize DES specifically was prepared on the surface of gold electrode through the molecular self-assembly technique. Gold nanoparticles (AuNPs) were coupled with anti-DES antibodies to amplify the signal of QCM. DES was detected through competitive immunoassay. At the same time, five gold electrodes were plated on a single langasite crystal in order to prepare an arrayed LCM sensor. The reliability and efficiency of the arrayed sensor were studied. The QCM sensor exhibits a linear detection range from 16 to 500 ng/mL and a detection limit of 13 ng/mL. The recovery rate of DES in the milk samples was 98.0-104.8%. By using structural analogs, the QCM sensor platform was demonstrated to be specific for the detection of DES. The arrayed LCM sensor was developed successfully and it could detect DES with arrayed method.