Immobilization of oligonucleotides onto a glass support via disulfide bonds: A method for preparation of DNA microarrays

Abstract

The covalent attachment of disulfide-modified oligonucleotides to a mercaptosilane-modified glass surface is described. This method provides an efficient and specific covalent attachment chemistry for immobilization of DNA probes onto a solid support. Glass slides were derivatized with 3- mercaptopropyl silane for attachment of 5-prime disulfide-modified oligonucleotides via disulfide bonds. An attachment density of approximately 3 x 105 oligonucleotides/μm2 was observed. Oligonucleotides attached by this method provided a highly efficient substrate for nucleic acid hybridization and primer extension assays. In addition, we have demonstrated patterning of multiple DNA probes on a glass surface utilizing this attachment chemistry, which allows for array densities of at least 20,000 spots/cm2.