Recent Developments in Ion Mobility Mass Spectrometry for Bioanalysis

Aug 22, 2014
Volume 10, Issue 15

This article reviews recent developments that aim to address the conflicting demands for higher throughput, sensitivity, and selectivity in bioanalysis applications.

Photo Credit: Rafe Swan/Getty Images
Bioanalysis is a key part of a candidate drug's pharmacokinetic and pharmacodynamic characterization. Liquid chromatography coupled with tandem mass spectrometry (LC–MS–MS) has been used widely by pharmaceutical laboratories over the past 30 years to quantify drugs and their metabolites in biological matrices. Numerous advances in instrumentation, technology, methods, and software during this period have led to significant improvements in speed, and sensitivity alone has increased by seven orders of magnitude.1

Analyzing drugs in biological samples has always been challenging as a result of matrix effects or background interference, and researchers have tried to overcome this in the past with various method developments and sample preparation steps. More recently, addressing the issue has been complicated further by the need to increase sample analysis throughput, while at the same time being able to detect compounds at increasingly lower levels.

One approach has been to use ion mobility mass spectrometry (IMS), which combines ion separation techniques with mass spectrometry, including quadrupole or time-of-flight (TOF). IMS has been commonly used for the selective detection of compounds in biological samples.2,3 Ion mobility can operate at atmospheric pressure, unlike mass spectrometry, and this allows the incorporation of atmospheric pressure ionization.3 This enables additional selectivity during sample introduction, but IMS is typically too slow and not sufficiently rugged for quantitative bioanalysis applications.4