Microcantilever Array Sensors for Biomolecular Detection

Microcantilever based sensors are a new class of extremely sensitive sensor device that is currently being developed for chemical and biological detection. In the work described here, Oligonucleotide probes for DNA and mRNA were immobilized on the gold coated side of silicon microcantilevers via thiol linkers and exposed to complementary and non-complementary sequences using microliter volumes of sample solutions. The surface stress generated by specific recognition between complementary sequences could be monitored as it induced a deflection of the cantilever. The deflection response of up to sixteen cantilevers could be read in parallel using a new optical reader based on an array of laser diodes (VCSELs). As a model system for affinity binding, biotin-streptavidin interaction was also monitored against unspecific streptavidin adsorption