Polyurethane based on polypropylene glycol(PPG) and TDI using 3,3\|dichloride\|4,4\|methylenedianiline(MOCA) as the crosslinker is presented for the first time to fabricate molecular stamps(PU stamps) for the synthesis of DNA microarray with contact procedure. The predictability of the process is achieved by utilizing commercially available starting materials. SEM analysis of the morphology of PU stamps and photoresist motherboard showed that PU elastomer could replicate subtly the motherboards patterns with a high fidelity. It was proved from the contact angle measurement that PU stamps surface has a good affinity with acetonitrile, which guarantee the well\|distribution of DNA monomers on patterned stamps. Laser confocal fluorescence microscopy images of oligonucleotide arrays confirm that polyurethane is an excellent material for molecular stamps.
