Separation and determination of carnosine-related peptides using capillary electrophoresis with laser-induced fluorescence detection.
A capillary electrophoresis (CE) method with laser-induced fluorescence (LIF) detection was developed for the separation and detection of carnosine-related peptides (carnosine, anserine, and homocarnosine). A sensitive and fluorogenic regent, 3-(4-carboxybenzoyl) quinoline-2-carboxaldehyde (CBQCA) was selected as a precapillary labeling reagent for imidazole dipeptides to form isoindole derivatives. The optimized molar ratio between CBQCA and peptide was found to be 75:1, and 50 mmol/L borate buffer (pH 9.2) was used for the derivatization in order to achieve good efficiency. Three imidazole dipeptides were baseline-separated within 20 min by using 112 mmol/L sodium borate (pH 10.4-10.8) as running buffer. Concentration detection limits (signal-to-noise ratios) for carnosine, anserine, and homocarnosine were 4.73, 4.37, and 3.94 nmol/L, respectively. This method has been applied to the analysis of human cerebrospinal fluid (CSF) and meat dry powder of pig and sheep. Recoveries were in the range of 82.9-104.8% for homocarnosine in CSF. For carnosine and anserine, the recoveries are 98.3% and 80.2% in meat dry powder of pig and 111.2% and 112.8% in meat dry powder of sheep, respectively.
Huang
Ying
Y
Department of Chemistry, Fuzhou University, Fujian, China.
Duan
Jianping
J
Chen
Hongqing
H
Chen
Min
M
Chen
Guonan
G
D000293:Adolescent; D000328:Adult; D000818:Animals; D000861:Anserine / Q000302:isolation & purification*; D001565:Benzoates; D002336:Carnosine / Q000031:analogs & derivatives* / Q000302:isolation & purification*; D002555:Cerebrospinal Fluid / Q000737:chemistry*; D019075:Electrophoresis, Capillary / Q000379:methods*; D006801:Humans; D007834:Lasers; D008460:Meat / Q000032:analysis; D008875:Middle Aged; D009132:Muscles / Q000737:chemistry; D010455:Peptides / Q000302:isolation & purification*; D011804:Quinolines; D012756:Sheep; D013050:Spectrometry, Fluorescence; D034421:Sus scrofa
D001565:Benzoates; D010455:Peptides; D011804:Quinolines; C069617:3-(4-carboxybenzoyl)-2-quinolinecarboxaldehyde; C005038:homocarnosine; D002336:Carnosine; D000861:Anserine