Study of ssDNA immobilization and hybridization on gold substrate with quartz crystal microbalance

Abstract

The aim of this study was to apply QCM for the registration of synthetic ssDNA fragments binding to SAM and for DNA hybridization. 5’-aminoalkyl- oligonucleotides were successfully covalently immobilized onto SAM /Au via carboxylate ester linkages, and we observed a reduction in the frequency of 91 Hz. For duplex formation, the oligo-50mer after incubation with 10× ligation buffer was placed on an ssDNA-modified surface, and we observed a reduction in the frequency of 112 Hz. It means that covalently we immobilized 629 ng/cm2 of 5’-amino-alkyl-oligonucleotides. After the duplex formation, the gold-coated quartz mass increased by 776 ng/cm2. Keywords: QCM, ssDNA, DNA sensor