oxamer, oxford gene technology ltd sandy lane, yarnton, oxford ox5 1pf, uk 1department of biochemistry, university of oxford south parks road, oxford ox1 3qu, uk
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in this paper, we demonstrate in situ synthesis of oligonucleotide probes on poly(dimethylsiloxane) (pdms) microchannels through use of conventional phosphoramidite chemistry. pdms polymer was moulded into a series of microchannels using standard soft lithography (micro-moulding), with dimensions <100 μm. the surface of the pdms was derivatized by exposure to ultraviolet/ozone followed by vapour phase deposition of glycidoxypropyltrimethoxysilane and reaction with poly(ethylene glycol) spacer, resulting in a reactive surface for oligonucleotide coupling. high, reproducible yields were achieved for both 6mer and 21mer probes as assessed by hybridization to fluorescent oligonucleotides. oligonucleotide surface density was comparable with that obtained on glass substrates. these results suggest pdms as a stable and flexible alternative to glass as a suitable substrate in the fabrication and synthesis of dna microarrays.
the uptake of dna microarrays into the academic and commercial arena over the past 10 years has been rapid owing to their usefulness in high-throughput, parallel gene expression, single nucleotide polymorphism analysis and comparative genome hybridization (1 6). further applications of this technology encompass topics such as optimization of antisense oligonucleotides (7), molecular hybridization studies (8,9), mutation identification via gene resequencing (10 12) and analysis of dna protein interactions (13). microarrays are now widely available from a number of companies.
microarrays are fabricated by spotting or ink-jetting cloned dna or pre-synthesized oligonucleotides onto solid surfaces; or they are fabricated through a variety of in situ techniques including ink-jetting, photolithography and novel electrochemistry (14,15). in all cases, the oligonucleotide probes are synthesized using well-established phosphoramidite chemistry (16,17).......