Microfluidic performance comparison

We are witnessing a continuous and natural evolution of biological systems, and in a similar manner, our tools, methods and approaches evolve as well. It took almost a century for liquid chromatography and mass spectrometry to reach the performance level that we are enjoying today. In comparison, microfluidics is a relatively new area of research that evolved into analytical instrumentation only during the past 15-20 years. Miniaturization is clearly the very next step that will follow in instrument development and will have to be assimilated in our techniques and practices.6 8 Why will this have to happen Because only miniaturization will enable the reliable handling of trace sample amounts and the implementation of innovative operational principles that are not feasible in the macroscale setting. 

Generally, off-line and on-line analysis approaches from microfluidic devices are complementary. Despite the strengths and weaknesses associated with either approach, a comparison can be made with regard to performance, ease of implementation and the robustness of the approach. Off-line approaches are... 

Li and coworkers described the separation of FITC and FllC-labeled antihuman IgG by zone electrophoresis in a glass microchip. The two compounds were electrokinetically injected into the separation channel for 2 s and separated in less than 12 s. A comparison between the separation performance in capillary and microchip showed that higher efficiency was achieved in the microchip format due to the shorter separation length and the higher electric field that were applied in microfluidic structures. 

Comparisons between devices are complicated by the effect of initial distribution on mixing effectiveness. If initial distributions are significantly different, care must be taken when making any device comparisons, even when the mixing analysis scheme and applied mixing measure are the same. One approach is to characterize the mixing performance of a device for several relevant initial distributions, a practice that has not been standard in the evaluation of microfluidic mixers. 

To date, there has been little work done in attempting to use such metallic alloys as the insert in micro injection-molding. It is the aim of this paper to conduct a brief comparison of the geometrical and surface qualities of a set of microfluidic features that will be fabricated onto silicon and metallic glass inserts. Micro injection-molding using the metallic glass insert with COC and PMMA resins will be subsequently performed. The molded samples will also be analyzed. 

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