Fluorescence-monitored zero dead-volume nanoLC-microESI-QIT-TOF MS for analysis of fluorescently tagged glycosphingolipids.

An analysis of the glycan processing event is of particular importance to understand the nontemplate dependent synthetic mechanism of the multiple glycosylation reactions taking place in the Golgi apparatus in connection with the post-translational modification of biomolecules. In our efforts to address the issue, we constructed an analysis platform using nano-liquid chromatography (LC), which also worked as a spray tip, with an optical-fiber-based blue (470 nm) light emitting diode (LED)-induced fluorescence (520 nm) detector coupled with a microelectrospray ionization (ESI)-quadrupole ion trap (QIT)-time of flight (TOF) mass spectrometer (MS). This system was designed to enable both quantitative and qualitative analyses of fluorescently tagged molecules such as BODIPY-tagged lactosylceramide.

Sequential enzymatic glycosyltransfer reactions on a microfluidic device: Synthesis of a glycosaminoglycan linkage region tetrasaccharide.

A microfluidic chip carrying three reaction chambers was designed and constructed to examine sequential multiple enzymatic reactions. The synthesis of oligosaccharides in living cells is carried out in the Golgi apparatus where multiple enzymes such as glycosidase and glycosyltransferases act on a variety of substrates to generate glycoconjugates that include glycolipids and glycoproteins. The regulatory mechanism of the process however remains unknown.

On-line determination of trace sulfur dioxide in air by integrated microchip coupled with fluorescence detection.

A microchip-based method was developed for on-line determination of trace sulfur dioxide (SO(2)) in air. Gaseous SO(2), which diffused through the porous glass materials on the microchip, was absorbed into an absorption solution of triethanolamine (TEA) as sulfite ions and reacted with N-(9-acridinyl)maleimide (NAM), which was used as a fluorescent reagent. The fluorescence of NAM-sulfite in micro-fluidic channel was detected.