A Spray-Atomization Ambient Plasma Ion Source for Coupling Ultra High Performance Liquid Chromatography to Tandem Mass Spectrometry

ADAM KAYLOR; PRABHA DWIVEDI; MARIA E. MONGE; FACUNDO M. FERNÁNDEZ

Atlanta

Conferencia; Georgia Tech Research and Innovation Conference; 2013

Liquid Chromatography coupled to Mass Spectrometry (LC-MS) or tandem Mass Spectrometry (LC-MS/MS) is the mainstay of modern analytical laboratories involved in pharmaceutical development, food safety, forensics, metabolomics, and proteomics. Since the late 80´s, the coupling of liquid phase separations with MS relies on electrospray ionization (ESI). However, ESI is limited in the sense that ionization is suppressed in the presence of many organic solvents and typical buffers needed for better liquid phase separations. Additionally, only polar analytes are ionizable by ESI, limiting the diversity of the chemical inventory that can be successfully transferred to the gas-phase. Direct Analysis in Real Time-Mass Spectrometry (DART-MS) is a new analytical technology that allows for real-time noncontact detection of gases, liquids, and materials on surfaces under ambient conditions with little to no sample preparation. These features make DART-MS well suited for organic reaction monitoring and impurity identification when non-ESI-friendly matrices are present. In this work we present an innovative interface that enables the coupling of LC to MS and MS/MS via spray-atomization followed by DART chemical ionization. The spray-DART interface is characterized using a series of test compounds with varying liquid-phase acid base properties and gas-phase proton affinities. Experimental results showcasing this new type of instrumentation will be presented to demonstrate chemically distinct ion population generated by ESI and spray-DART mechanisms and the advantages of the developed technology for chemically harsh and complex sample analysis.