| Novel methods of polymer microchip fabrication have been developed using hot embossing techniques. An epoxy resin has been used to clone hot embossing stamps made from a master with either positive or negative relief structures. The epoxy stamps are inexpensive, and capable of reproducing structures of various shapes, and sizes measuring less than 1mum. The epoxy structures can be embossed into poly(methylmethacrylate) (PMMA) without any loss of feature integrity after fifty embossing cycles.;A second, low temperature solvent bonding protocol was developed to allow enzymes to be patterned on the PMMA surface prior to bonding. Two methods of enzyme immobilization were used, and the performance of each was investigated according to the longevity of the enzyme microreactor and the length of microchannel used for enzyme immobilization. The efficiency of the immobilized enzyme was characterized according the digested protein sequence coverage and the number of missed cleavages.;After microstructures are embossed, a cover plate must be bonded to the polymer substrate to complete the microfluidic chip. Novel methods of surface modification have been developed, including acid hydrolysis, aminolysis and plasma modification of PMMA, and the effects of each on bond strength have been studied. Solvent systems have also been designed to soften the surface of PMMA during bonding while maintaining microchannel integrity. The solvent bonding system significantly increased the bond strengths for both unmodified and modified PMMA. |
