Interfacing capillary gel microfluidic chips with infrared laser desorption mass spectrometry
We report on the fabrication and performance of a gel microfluidic chip interfaced to laser desorption/ionization (LDI) mass spectrometry with a time-of-flight mass analyzer. The chip was fabricated from poly(methylmethacrylate) with a poly(dimethyl siloxane) cover. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis was performed in the channel of the microfluidic chip. After electrophoresis, the cover was removed and either the PDMS chip or the PMMA cover was mounted in a modified MALDI ion source for analysis. Ions were formed by irradiating the channel with 2.95 μm radiation from a pulsed optical parametric oscillator (OPO), which is coincident with IR absorption by N-H and O-H stretch of the gel components. No matrix was added. The microfluidic chip design allowed a decrease in the volume of material required for analysis over conventional gel slabs, thus enabling improvement in the detection limit to a pmol level, a three orders of magnitude improvement over previous studies in which desorption was achieved from an excised section of a conventional gel. © 2006 American Society for Mass Spectrometry.
Publication Source (Journal or Book title)
Journal of the American Society for Mass Spectrometry
Xu, Y., Little, M., & Murray, K. (2006). Interfacing capillary gel microfluidic chips with infrared laser desorption mass spectrometry. Journal of the American Society for Mass Spectrometry, 17 (3), 469-474. https://doi.org/10.1016/j.jasms.2005.12.003