Microfluidics-based electrospray ionization enhances the intrasource separation of lipid classes and extends identification of individual molecular species through multi-dimensional mass spectrometry: development of an automated high-throughput platform for shotgun lipidomics
Article first published online: 3 JUN 2008
Copyright © 2008 John Wiley & Sons, Ltd.
Rapid Communications in Mass Spectrometry
Volume 22, Issue 13, pages 2115–2124, 15 July 2008
How to Cite
Han, X., Yang, K. and Gross, R. W. (2008), Microfluidics-based electrospray ionization enhances the intrasource separation of lipid classes and extends identification of individual molecular species through multi-dimensional mass spectrometry: development of an automated high-throughput platform for shotgun lipidomics. Rapid Commun. Mass Spectrom., 22: 2115–2124. doi: 10.1002/rcm.3595
- Issue published online: 3 JUN 2008
- Article first published online: 3 JUN 2008
- Manuscript Accepted: 1 MAY 2008
- Manuscript Revised: 22 APR 2008
- Manuscript Received: 28 FEB 2008
- National Institutes of Health. Grant Number: P01 HL57278
- National Institute on Aging and National Institute for Diabetes and Digestive Diseases. Grant Number: R01 AG31675
Herein, we exploit the use of microfluidics and optimized Taylor cones for improved intrasource separation/selective ionization of lipid classes during electrospray ionization. Increased differential ionization of multiple phospholipid classes was achieved through microfluidics with chip-based ionization resulting in substantial enhancement of intrasource separation/selective ionization of phospholipid classes in comparison to the conventional ion source. For example, using myocardial lipid extracts, 3-fold improvements in intrasource separation/selective ionization of myocardial phospholipid classes were routinely realized in the negative-ion mode in the absence of LiOH or other basic modifiers in the infused sample solutions. Importantly, the relative ratios of ions corresponding to individual molecular species in each lipid class to a selected internal standard from myocardial extracts were nearly identical between the chip-based interface and the syringe-pump-driven capillary interface. Therefore, quantitation of individual lipid molecular species directly from biological extracts through comparisons with internal standards in each lipid class was readily accomplished with an accuracy and dynamic range nearly identical to those documented using the well-established direct syringe-pump-driven capillary interface. Collectively, the use of microfluidics and robotic sample handling substantially enhances intrasource separation of lipids in comparison to routine capillary interfaces and greatly facilitates the use of multi-dimensional mass spectrometry using shotgun lipidomics, thereby providing an automated and high-throughput platform for global analyses of cellular lipidomes. Copyright © 2008 John Wiley & Sons, Ltd.