Preparation of DNA chips using polyamine-oligonucleotide conjugates

A convenient and efficient method for three-dimensional immobilizing oligonucleotides on glass was developed using oligonucleotide derivatives bearing a polyamine linker (PA-oligo conjugates). Polyamine (polylysine, poly(lysine, phenylalanine), polyethyleneimine) residues stipulate durable fixation of such conjugates to the glass surface with a high yield (90-95%). A DNA fragment (414-mer) is hybridized specifically to an immobilized oligonucleotide.