AlanineLysine
ArginineMethionine
AsparaginePhenylalanine
Aspartic acidProline
CystineSerine
Glutamic acidTryptophan
GlutamineTyrosine
GlycineValine
IsoleucineThreonine
Leucine

Amino acids can be found in biological fluids and have key roles in many biological processes, such as protein synthesis, neurotransmission, and the regulation of metabolic pathways. Characteristically, branched-chain amino acids (BCAAs) (valine (Val), leucine (Leu), and isoleucine (Ile)) are involved in protein synthesis, while tyrosine (Tyr) and Phenylalanine (Phe) are intermediate metabolites in the biosynthesis of catecholamines. Also, γ-aminobutyric acid (GABA), glutamic acid (Glu), and taurine (Tau), act as neurotransmitters that modulate transmission in the synaptic cleft. It has been shown that alterations in levels of amino acids in biological fluids are related to many types of diseases such as diabetes, liver disease, kidney disease and different types of cancers. Therefore, there is a great need for the development of analytical methods that can detect these changes in levels of amino acids in biological samples (e.g. plasma, urine, and sweat) which subsequently could be used as biomarkers for early diagnosis and elucidation of mechanisms of diseases.

Our HILIC-MS/MS method covers all major amino acid providing unsurpassed sensitivity, specificity, wide dynamic range, robustness, and reproducibility. The method has been applied in a number of studies and matrices (CSF, blood, various other biological fluids and extracts).

Virgiliou, C., Sampsonidis, I., Gika, H.G., Raikos, N., Theodoridis, G.A. Development and validation of a HILIC-MS/MS multitargeted method for metabolomics applications (2015) Electrophoresis, 36 (18), pp. 2215-2225.