Piezoelectric Sensor for Determination of Genetically Modified Soybean Roundup Ready (R) in Samples not Amplified by PCR

Abstract

The chemically modified piezoelectrodes were utilized to develop relativelycheap and easy to use biosensor for determination of genetically modified Roundup Readysoybean (RR soybean). The biosensor relies on the immobilization onto goldpiezoelectrodes of the 21-mer single stranded oligonucleotide (probes) related to5-enolpyruvylshikimate-3-phosphate synthase (EPSPS) gene, which is an active componentof an insert integrated into RR soybean genome. The hybridization reaction between theprobe and the target complementary sequence in solution was monitored. The system wasoptimized using synthetic oligonucleotides, which were applied for EPSPS gene detectionin DNA samples extracted from animal feed containing 30% RR soybean amplified by thePCR and nonamplified by PCR. The detection limit for genomic DNA was in the range of4.7·105 numbers of genom copies contained EPSPS gene in the QCM cell. The propertiessuch as sensitivity and selectivity of piezoelectric senor presented here indicated that it could be applied for the direct determination of genetically modified RR soybean in the samples non-amplified by PCR.