A versatile multi-platform biochip surface attachment chemistry

A versatile DNA spotting and immobilization method for covalent attachment of amino-modified probe oligonucleotides in microarray format at glass, native silicon dioxide and CVD silicon nitride substrates is reported. Optimal probe spot printing and attachment buffers are identified for each substrate. Relative areal densities of immobilized probes as measured by epi-fluorescence microscopy vary with substrate type reflecting differences in surface morphology and chemistry. Target oligonucleotide hybridization occurs at glass and nitride supported probe microarrays in an efficient and reproducible manner with excellent measured fluorescence signal-to-background.