ELECTROSPRAY AND NANOSPRAY IONIZATION OF DISCRETE SAMPLES IN DROPLET FORMAT
摘要
<p>Droplets or plugs within multiphase microfluidic systems have rapidly gained interest as a way to manipulate samples and chemical reactions on the femtoliter to microliter scale. Chemical analysis of the plugs remains a challenge. It has been discovered that nanoliter plugs of sample separated by air or oil can be analyzed by electrospray ionization mass spectrometry when pumped directly into a fused silica nanospray emitter nozzle. Using leu-enkephalin in methanol and 1% acetic acid in water (50:50 v:v) as a model sample, we found carry-over between plugs was <0.1% and relative standard deviation of signal for a series of plugs was 3%. Detection limits were 1 nM. Sample analysis rates of 0.8 Hz were achieved by pumping 13 nL samples separated by 3 mm long air gaps in a 75 mum inner diameter tube. Analysis rates were limited by the scan time of the ion trap mass spectrometer. The system provides a robust, rapid, and information-rich method for chemical analysis of sample in segmented flow systems.</p>
申请公布号
EP2443432(A2)
申请公布日期
2012.04.25
申请号
EP20100790290
申请日期
2010.06.18
申请人
THE REGENTS OF THE UNIVERSITY OF MICHIGAN OFFICE OF TECHNOLOGY TRANSFER;NEW OBJECTIVE, INC.;MILESTONE DEVELOPMENT SERVICES
发明人
KENNEDY, ROBERT;PEI, JIAN;LI, QIANG;LEE, MIKE, S.;VALASKOVIC, GARY, A.