Attachment of DNA to microfabricated arrays with self-assembled monolayer

A novel approach of fabricating sub-10-μm patterns on silicon surfaces by electron beam (EB) lithography for attachment of oligonucleotides was described. The shape of the microfabricated arrays was observed to be regular by optical microscopy. An octadecyltrimethoxysilane (ODS) monolayer was deposited on the regions outside the patterned areas to minimize the nonspecific binding of biomolecules. Cy 5-labeled target DNA was hybridized to both complementary and noncomplementary oligonucleotides that were covalently anchored to micropatterns. As a result, the micropatterns where specific binding occurred show strong signals, whereas no signals are observed in the case of nonspecific binding. These data indicate that miniature micro- and nano-arrays will find applications in biochips and biosensors.