We are developing next-generation assays for biofuels research using microfluidic technologies to provide significant improvement over conventional platforms in throughput, sensitivity, multiplexing and speed of analysis. To develop these microscale assays we utilize technologies covering a wide spectrum of complexity based on the requirements of the assays. For example, using off-the-shelf components we have developed a microtiter plate-based assay for screening cellulases against heterogeneous substrates. This approach relies on in-situ biomass regeneration in micro-volumes to volumetrically meter biomass (sub-mg loading) and also precisely control the amount of residual IL for screening activities of novel IL-tolerant cellulases. We have also developed more sophisticated platforms for screening of lignocellulolytic enzymes using microfluidic chip for electrophoretic analysis of glycans. These chips are being used to screen genetically-engineered enzymes, assess performance of pretreatment processes, and for discovering cellulase activities in microbial communities. We are also developing high throughput microchips to perform combinatorial DNA assembly for optimization of biofuel synthesis pathways