New Advances in Amino Acid Profiling in Biological Samples by Capillary Electrophoresis-Mass Spectrometry

Methods Mol Biol. 2019;2030:327-350. doi: 10.1007/978-1-4939-9639-1_25.

Abstract

Capillary electrophoresis-mass spectrometry (CE-MS) offers a high efficiency microseparation platform for amino acid profiling when analyzing volume-restricted biological samples, such as a dried blood spot punch. Direct analysis of amino acids and their analogs is routinely achieved using strongly acidic buffer conditions under positive-ion mode detection with a coaxial sheath liquid interface for electrospray ionization (ESI). New advances in online sample preconcentration, pre-column chemical derivatization, and/or low flow/sheathless CE-MS interface designs can further improve sensitivity while allowing for resolution of amino acid stereoisomers and labile aminothiols with low nanomolar detection limits. Additionally, multiplexed separations in CE-MS based on serial injection of seven or more samples within a single run greatly boosts sample throughput (<2-3 min/sample) without added infrastructure costs while allowing for stringent quality control and signal batch correction. Accurate prediction of the electromigration behavior of amino acids and their analogs offers a convenient approach for structural elucidation that is complementary to high-resolution MS and MS/MS. Simultaneous analysis of amino acids together with other classes of ionic metabolites by CE-MS allows for comprehensive metabolomic screening as required for new advances in clinical medicine, nutritional sciences, and population health.

Keywords: Amino acids; CE-MS; Capillary electrophoresis; Dried blood spots; Mass spectrometry; Plasma; Serum; Urine.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acids / analysis*
  • Amino Acids / chemistry
  • Dried Blood Spot Testing / instrumentation
  • Dried Blood Spot Testing / methods
  • Electrophoresis, Capillary / instrumentation
  • Electrophoresis, Capillary / methods*
  • Erythrocytes / chemistry
  • Humans
  • Limit of Detection
  • Spectrometry, Mass, Electrospray Ionization / instrumentation
  • Spectrometry, Mass, Electrospray Ionization / methods*
  • Stereoisomerism
  • Urinalysis / instrumentation
  • Urinalysis / methods

Substances

  • Amino Acids