A versatile aptasensor material for lab-on-chip analytical applications
Here, we present a LoC device functionalized with an aptasensor material based on poly 2-(hydroxyethylmethacylate) (PHEMA) brushes, for monitoring the presence of the mycotoxin Ochratoxin A (OTA). OTA has been recognized toxic for different organs and its early detection in food commodities, by using this LoC in the production site, would reduce the risks for human and animal health. The aptamer, having high affinity versus OTA (OTA-aptamer), is immobilized into the PHEMA layer grown within a microfluidic channel. Afterwards, PHEMA is derivatized to immobilize, through the formation of an amide bond. Subsequently, PHEMA is treated with a solution of [Ru(phen)2(dppz)]2+, a DNA intercalating dye, whose fluorescence is poor in aqueous solutions but intense when intercalated into the DNA. The functionalized chip is coupled with amorphous silicon photosensors, which monitor the fluorescent signal.