Monitoring Enzymatic Reactions in Real Time Using Venturi Easy Ambient Sonic-Spray Ionization Mass Spectrometry
2016 (English)In: Analytical Chemistry, ISSN 0003-2700, E-ISSN 1520-6882, Vol. 88, no 12, 6195-6198 p.Article in journal (Refereed) PublishedText
We developed a technique to monitor spatially confined surface reactions with mass spectrometry under ambient conditions, without the need for voltage or organic solvents. Fused-silica capillaries immersed in an aqueous solution, positioned in close proximity to each other and the functionalized surface, created a laminar flow junction with a resulting reaction volume of similar to 5 pL. The setup was operated with a syringe pump, delivering reagents to the surface through a fused silica capillary. The other fused-silica capillary was connected to a Venturi easy ambient sonic-spray ionization source, sampling the resulting analytes at a slightly higher flow rate compared to the feeding capillary. The combined effects of the inflow and outflow maintains a chemical microenvironment, where the rate of advective transport overcomes diffusion. We show proof-of-concept where acetylcholinesterase was immobilized on an organosiloxane polymer through electrostatic interactions. The hydrolysis of acetylcholine by acetylcholinesterase into choline was monitored in real-time for a range of acetylcholine concentrations, fused-silica capillary geometries, and operating flow rates. Higher reaction rates and conversion yields were observed with increasing acetylcholine concentrations, as would be expected.
Place, publisher, year, edition, pages
2016. Vol. 88, no 12, 6195-6198 p.
IdentifiersURN: urn:nbn:se:uu:diva-299893DOI: 10.1021/acs.analchem.6b01246ISI: 000378470200019PubMedID: 27249533OAI: oai:DiVA.org:uu-299893DiVA: diva2:950384
FunderSwedish Research Council, 2015-00406