Chengwu Li | PubMed Health

PubMed2005

Magnetically actuated micromixing on an array-pattern microfluidic chip for immunoassay of human thyrotropin.

A novel array-pattern ring microfluidic chip has been designed and fabricated with ITO glass, and a low-cost, easy-to-use active magnetic mixer is developed. The mixer consists of externally driven magnetic stir plates and ferromagnetic microneedles as active mobile stirrers in the microchannel. Mixing performance in the microfluidic chip has been experimentally characterized by chemiluminescence immunoassay of human thyrotropin (TSH) and compared with tube-based chemiluminescence immunoassay. The mixing method proposed in this study can be readily applied to integrated microfluidic systems, such as micro-total-analysis systems, lab-on-a-chip, and so on.

Equipment Design↗

PubMed2003

Fabrication and characterization of poly(methyl methacrylate) microchannels by in situ polymerization with a novel metal template.

A stainless steel template for the fabrication of plastic microfluidic devices has been developed by photolithography and chemical etching technique. The preparation process of the template is simple, rapid, and low-cost. The cross sectional profiles of raised microchannels on the template are trapezoidal. The surface roughness of the templates was controlled down to 190 nm. The template can be used repeatedly to generate devices reproducibly. The microfluidic devices of poly(methyl methacrylate) (PMMA) were fabricated by in situ polymerization using the templates. The reproducibility of the fabricated microchannel is high and the relative standard deviation is 0.7% by the in situ polymerization approach. Some physical properties of the polymerized microchannels were characterized including the transparency, the thermal deformation temperature, and the dimensional information. Current monitoring was used to evaluate the electroosmotic flow within the microchannels under the electric field strength of 300 V/cm.

Equipment Design↗