Biosensors by means of the laser induced forward transfer technique

This work presents the direct laser printing of thiol-modified oligonucleotides onto the surface of 3-glycidoxypropyltrimethoxysilane (GOPTS)-functionalized ultra-thin Low temperature oxide (LTO)/Si membranes for the fabrication of a label-free capacitive biosensor. During the hybridization of the target oligonucleotides with their immobilized complementary strands, various interaction forces develop, which contribute toward the deflection of the ultrathin LTO membranes, resulting in a capacitance shift. A number of different parameters were investigated for the laser printing conditions of the oligonucleotides that in turn affect the maximum deflection of the membranes and therefore the capacitance variation.