Analysis of amino acids and biogenic amines in biological tissues as their o-phthalaldehyde/ethanethiol/fluorenylmethyl chloroformate derivatives by high-performance liquid chromatography

Advancement in the derivatizations of the amino groups with the o-phthaldehyde-thiol and with the 9-fluorenylmethyloxycarbonyl chloride reagents

“…Before going into details it is worthy of mention that in the literature as model compounds of stability studies (from the beginning and thereafter continuously), glycine, GABA, ␤-alanine, histidine, ornithine and lysine have been selected as the less stable ones: in shortage of knowledge of their intrinsic characteristics, clarified recently [3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18][19]. Since (i) these six AAs provide more than one OPA derivative, (ii) resulting in products of similar high stability as any other AAs: so long as, the total of their FL or UV responses, i.e., the sum of derivatives obtained from the given AA were taken into account in their quantitation.…”

“…The introduction of NAC as SH-group containing alternative was explained mainly in qualitative manner [45]. [13][14][15][16][17][18][19], proved that all of them are significantly more stable than they are generally believed to be: (i) the single derivatives providing 20 AAs [11], as OPA/MPA or OPA/NAC derivatives exhibited <4% degradation, even after 6 h, the OPA/MCE ones after 75 min reaction time, while the OPA/ET derivatives remain stable even after 6 h (ii) The AAs providing more than one derivative (glycine, GABA, ␤-alanine, histidine, ornithine and lysine), evaluating the total of their peaks, are as stable as the single derivative furnishing OPA-AAs [3][4][5][6]18]. …”

“…In order to get answer to these questions in author's laboratory two approaches were followed: stoichiometric investigations were carried out with simultaneous PDA and FL detections [3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18][19] while structure elucidation were confirmed by on line HPLC/PDA/mass spectrometry (MS) applying electro spray ionization (ESI) in the positive mode [7,12,13,15]. The literature contains a variety of contradictory conditions regarding derivatization conditions.…”

“…; () = in parentheses percentages, expressed in the number of the total, given in the last two horizontal line. own experiences [3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18][19] the following questions had to be answered:…”

In Salmonella enterica, Ethanolamine Utilization Is Repressed by 1,2-Propanediol To Prevent Detrimental Mixing of Components of Two Different Bacterial Microcompartments

“…Ethanolamine was determined by HPLC in the W. M. Keck Metabolomics Facility at Iowa State University using the o-phthaldialdehyde (OPA) fluorescence method of amine detection (49,50). Buffer A consisted of 10% methanol-90% sodium phosphate (pH 7.3), and buffer B was 80% methanol-20% sodium phosphate (pH 7.3).…”