Directive 2002/46/EC of the European Parliament and of the Council of 10 June 2002 on the approximation of the laws of the Member States relating to food supplements. pp. 51–57.

Boldyrev AA, Aldini G, Derave W. Physiology and pathophysiology of carnosine. Physiol Rev. 2013;93(4):1803–45. https://doi.org/10.1152/physrev.00039.2012.

Article  CAS  PubMed  Google Scholar 

Dutka TL, Lamboley CR, McKenna MJ, Murphy RM, Lamb GD. Effects of carnosine on contractile apparatus Ca2+ sensitivity and sarcoplasmic reticulum Ca2+ release in human skeletal muscle fibers. J Appl Physiol. 2012;112(5):728–36. https://doi.org/10.1152/japplphysiol.01331.2011.

Article  CAS  PubMed  Google Scholar 

Hoffman JR, Ratamess NA, Faigenbaum AD, Ross R, Kang J, Stout JR, Wise JA. Short-duration β-alanine supplementation increases training volume and reduces subjective feelings of fatigue in college football players. Nutr Res. 2008;28(1):31–5. https://doi.org/10.1016/j.nutres.2007.11.004.

Article  CAS  PubMed  Google Scholar 

Hoffman JR, Ostfeld, Stout JR, Harris RC, Kaplan Z, Cohen H. β-Alanine supplemented diets enhance behavioral resilience to stress exposure in an animal model of PTSD. Amino Acids. 2015;47(6):1247–1257. https://doi.org/10.1007/s00726-015-1952-y.

Thalacker-Mercer AE, Gheller ME. Benefits and adverse effects of histidine supplementation. J Nutr. 2020;150(Issue Supplement_1):2588S–2592S. https://doi.org/10.1093/jn/nxaa229.

Di Matteo P, Bortolami M, Curulli A, Feroci M, Gullifa G, Materazzi S, Risoluti R, Petrucci R. Phytochemical characterization of malt spent grain by tandem mass spectrometry also coupled with liquid chromatography: bioactive compounds from brewery by-products. Front Biosci (Landmark Ed). 2023; 28(1):3. https://doi.org/10.31083/j.fbl2801003.

Dai Z, Wu Z, Jia S, Wu G. J Chromatogr B. Analysis of amino acid composition in proteins of animal tissues and foods as pre-column o-phthaldialdehyde derivatives by HPLC with fluorescence detection. 2014;964(1):116-127. https://doi.org/10.1016/j.jchromb.2014.03.025.

Aviram LY, McCooeye M, Mester Z. Determination of underivatized amino acids in microsamples of a yeast nutritional supplement by LC-MS following microwave assisted acid hydrolysis. Anal Methods. 2016;8(22):4497–503. https://doi.org/10.1039/C6AY00407E.

Article  CAS  Google Scholar 

Wang LW, Su SF, Zha J, He XL, Fu SY, Wang B, Wang YF, Wang DQ, Yun NN, Chen X, Belobrajdic DP, Terigele, Li XD, Jiang LL, He JF, Liu YB. Effects of dietary oat supplementation on carcass traits, muscle metabolites, amino acid profiles, and its association with meat quality of small-tail Han sheep. Food Chem. 2023;411(15):135456. https://doi.org/10.1016/j.foodchem.2023.135456.

Raimbault A, Dorebska M, West C. A chiral unified chromatography–mass spectrometry method to analyze free amino acids. Anal Bioanal Chem. 2019;411:4909–17. https://doi.org/10.1007/s00216-019-01783-5.

Article  CAS  PubMed  Google Scholar 

Wang Y, Zhao Z, Qin J, Liu H, Liu A, Xu M. Rapid in situ analysis of L-histidine and α-lactose in dietary supplements by fingerprint peaks using terahertz frequency-domain spectroscopy. Talanta. 2020;208: 120469. https://doi.org/10.1016/j.talanta.2019.120469.

Article  CAS  PubMed  Google Scholar 

De Silva M, Opallage PM, Dunn RC. Direct detection of inorganic ions and underivatized amino acids in seconds using high-speed capillary electrophoresis coupled with back-scatter interferometry. Anal Methods. 2021;13(11):1311–434. https://doi.org/10.1039/D0AY02218G.

Article  Google Scholar 

Tůma P, Sommerová B, Koval D, Šiklová M, Koc M. Plasma levels of creatine, 2-aminobutyric acid, acetyl-carnitine and amino acids during fasting measured by counter-current electrophoresis in PAMAPTAC capillary. Microchem J. 2023;1878: 108426. https://doi.org/10.1016/j.microc.2023.108426.

Article  CAS  Google Scholar 

Yu YL, Shi MZ, Zhu SC, Cao J. Rapid stacking of amino acids in soybean and Dendrobium officinale by on-capillary sandwich derivatization in capillary electrophoresis. Food Res Int. 2022;162(Part B);11207. https://doi.org/10.1016/j.foodres.2022.112071.

Costa BMC, Prado AA, Oliveira TC, Bressan LP, Munoz RAA, Batista AD, Silva JAF, Richter EM. Fast methods for simultaneous determination of arginine, ascorbic acid and aspartic acid by capillary electrophoresis. Talanta. 2019;204(June):353–8. https://doi.org/10.1016/j.talanta.2019.06.017.

Article  CAS  PubMed  Google Scholar 

Duong HA, Vu MT, Nguyen TD, Nguyen MH, Mai TD. Determination of 10-hydroxy-2-decenoic acid and free amino acids in royal jelly supplements with purpose-made capillary electrophoresis coupled with contactless conductivity detection. J Food Compost Anal. 2020;87: 103422. https://doi.org/10.1016/j.jfca.2020.103422.

Article  CAS  Google Scholar 

Piestansky J, Matuskova M, Cizmarova I, Olesova D, Mikus P. Determination of branched-chain amino acids in food supplements and human plasma by a CE-MS/MS method with enhanced resolution. Int J Mol Sci. 2021;22(15):8261. https://doi.org/10.1016/j.jfca.2020.103422.

Article  CAS  PubMed  PubMed Central  Google Scholar 

Pormsila W, Krähenbühl S, Hauser PC. Determination of carnitine in food and food supplements by capillary electrophoresis with contactless conductivity detection. Electrophoresis. 2010;31(13):2186–91. https://doi.org/10.1002/elps.200900692.

Article  CAS  PubMed  Google Scholar 

Ribeiro da Silva M, Zaborowska I, Carillo S, Bones J. A rapid, Simple and sensitive microfluidic chip electrophoresis mass spectrometry method for monitoring amino acids in cell culture media. J Chromatogr A. 2021;11651:462336. https://doi.org/10.1016/j.chroma.2021.462336.

Li X, Xiao D, Ou XM, McCullm C, Liu YM. A microchip electrophoresis-mass spectrometric platform for fast separation and identification of enantiomers employing the partial filling technique. J Chromatogr A. 2013;1318:251–6. https://doi.org/10.1016/j.chroma.2013.10.020.

Article  CAS  PubMed  PubMed Central  Google Scholar 

Li X, Xiao D, Sanders T, Tchounwou PB, Liu YM. Fast quantification of amino acids by microchip electrophoresis-mass spectrometry Amino Acid Analysis. Anal Bioanal Chem. 2013;405(25):8131–6. https://doi.org/10.1007/s00216-013-7260-z.

Article  CAS  PubMed  PubMed Central  Google Scholar 

Tůma P. Monitoring of biologically active substances in clinical samples by capillary and microchip electrophoresis with contactless conductivity detection: a review. Anal Chim Acta. 2022;1225: 340161. https://doi.org/10.1016/j.aca.2022.340161.

Article  CAS  PubMed  Google Scholar 

Tanyanyiwa J, Abad-Villar EM, Fernández-Abedul MT, Costa-García A, Hoffmann W, Guber AE, Herrmann D, Gerlach A, Gottschlich N, Hauser PC. High-voltage contactless conductivity-detection for lab-on-chip devices using external electrodes on the holder. Analyst. 2003;128(8):1019–22. https://doi.org/10.1039/b304469f.

Article  CAS  Google Scholar 

J. Tanyanyiwa, Abad-Villar EM, Hauser PC. Contactless conductivity detection of selected organic ions in on-chip electrophoresis. Electrophoresis. 2004;25(6):903–908. https://doi.org/10.1002/elps.200305732.

Abad-Villar EM, Hauser PC. Determination of biochemical species on electrophoresis chips with an external contactless. Electrophoresis. 2005;26(19):3609–14. https://doi.org/10.1002/elps.200500149.

Article  CAS  PubMed  Google Scholar 

Li O, Tong Y, Chen Z, Liu C, Zhao S, Mo J. A glass / PDMS hybrid microfluidic chip embedded with integrated electrodes for contactless conductivity detection. Chromatographia. 2008;68(11):1039–44. https://doi.org/10.1365/s10337-008-0808-y.

Article  CAS  Google Scholar 

Xu Y, Liang J, Liu H, Hu X, Wen Z, Wu Y, Cao M. Characterization of a capacitance-coupled contactless conductivity detection system with sidewall electrodes on a low-voltage-driven electrophoresis microchip. Anal Bioanal Chem. 2010;397(4):1583–93. https://doi.org/10.1007/s00216-010-3675-y.

Article  CAS  PubMed  Google Scholar 

Tu P, Samcová E. Determination of 1-methylhistidine and 3-methylhistidine by capillary and chip electrophoresis with contactless. Electrophoresis. 2007;28(13):2174–80. https://doi.org/10.1002/elps.200600697.

Article  CAS  Google Scholar 

Sydes D, Kler PA, Zipfl P, Lutz D, Bouwes H, Huhn C. Chemical on-chip intermediate potential measurements for the control of electromigration in multi-channel networks in case of time-dependent potential changes. Sens Actuators B Chem. 2017;240:330–7. https://doi.org/10.1002/elps.200500149.

Article  CAS  Google Scholar 

Pukleš I, Páger C, Sakač N, Šarkanj B, Matasović, Samardžić M, Budetić M, Marković D, Jozanović M. Electrophoretic determination of L-carnosine in health supplements using an integrated lab-on-a-chip platform with contactless conductivity detection. Int J Mol Sci. 2023;24:14705. https://doi.org/10.3390/ijms241914705.

Jiang X, Xia Z, Wei W, Gou Q. Direct UV detection of underivatized amino acids using capillary electrophoresis with online sweeping enrichment. J Sep Sci. 2009;32(11):1927–33. https://doi.org/10.1002/jssc.200900013.

Article  CAS  PubMed  Google Scholar 

Rita Steed – Manual of analysis of amino acids by HPLC. Agilent Technologies. 2010; Inc 800–227–9770.

Tůma P, Opekar F, Dlouhý P. Capillary and microchip electrophoresis with contactless conductivity detection for analysis of foodstuffs and beverages. Food Chem. 2022;375: 131858. https://doi.org/10.1016/j.foodchem.2021.131858.

Article  CAS  PubMed  Google Scholar 

Adımcılar V, Öztekin N, Erim FB. A direct and sensitive analysis method for biogenic amines in dairy products by capillary electrophoresis coupled with contactless conductivity detection. Food Anal Methods. 2018;11(4):374–1379. https://doi.org/10.1007/s12161-017-1122-9.

Article  Google Scholar 

Hirokawa T, Okamoto H, Gosyo Y, Tsuda T, Timerbaev AR. Simultaneous monitoring of inorganic cations, amines and amino acids in human sweat by capillary electrophoresis. Anal Chim Acta. 2007;581(1):83–8. https://doi.org/10.1016/j.aca.2006.07.077.

Article  CAS  PubMed  Google Scholar 

Gag B, Sttidrf M, Kenndle E. Peak broadening in capillary zone electrophoresis. Elecrrophoresis. 1997;18:2123–33. https://doi.org/10.1002/elps.1150181203.

Article  Google Scholar 

Gong M, Wehmeyer KR, Stalcup AM, Limbach PA, Heineman WR. Study of injection bias in a simple hydrodynamic injection in microchip capillary electrophoresis. Electrophoresis. 2007;28(10):1564–71. https://doi.org/10.1002/elps.200600616.

Article  CAS  PubMed  PubMed Central  Google Scholar 

Gratzfeld-Huesgen A. Sensitive and reliable amino acid analysis in protein hydrolysates using the Agilent 1100 Series HPLC. Technical Note by Agilent Technologies. 1999; Publication Number 5968–5658E.

Syad AN, Shunmugiah KP, Kasi PD. Seaweeds as nutritional supplements: analysis of nutritional profile, physicochemical properties and proximate composition of G. acerosa and S. wightii. Biomedicine & Preventive Nutrition. 2013;3(2):139–144.

Baxter JH, Johns PW. Determination of free arginine, glutamine, and β-alanine in nutritional products and dietary supplements. Food Anal Methods. 2012;5:821–7.

Article  Google Scholar 

Raimbault A, Dorebska M, West C. A chiral unified chromatography-mass spectrometry method to analyze free amino acids. Anal Bioanal Chem. 2019;411(19):4909–17.

Article  CAS  PubMed  Google Scholar 

Duong HA, Vu MT, Nguyen TD, Nguyen MH, Mai TD. Determination of 10-hydroxy-2-decenoic acid and free amino acids in royal jelly supplements with purpose-made capillary electrophoresis coupled with contactless conductivity detection. J Food Compos Anal. 2020;87(3): 103422.

Article  CAS