A Piezoelectric Biosensor For DNA Hybridisation Detection

Abstract

In this paper the realisation of a piezoelectric biosensor for DNA hybridisation detection is reported. A biotinylated 25-mer, was immobilised on a (strept)avidin coated piezoelectric crystal; avidin was covalently bound to the thiol/dextran modified gold surface of the crystal. Hybridisation of the probe with a complementary sequence was detected. The device was able to distinguish among targets of different lengths. Many cycles of measurements could be performed on the same crystal surface regenerating the single strand with HCl (ImM). No signal was detected when the probe reacted with a non complementary sequence. The same experiments were performed immobilising the biotinylated DNA probe on the gold surface coated with avidin by adsorption and the results were compared.

Key Words:

• piezoelectric biosensors
• DNA
• hybridisation