Rapid determination of amino acids in neonatal blood samples based on derivatization with isobutyl chloroformate followed by solid-phase microextraction and gas chromatography/mass spectrometry.
The purpose of this study was to develop a simple, rapid and sensitive analytical method for determination of amino acids in neonatal blood samples. The developed method involves the employment of derivatization and a solid-phase microextraction (SPME) technique together with gas chromatography/mass spectrometry (GC/MS). Amino acids in blood samples were derivatized by a mixture of isobutyl chloroformate, methanol and pyridine, and the N(O,S)-alkoxycarbonyl alkyl esters thus formed were headspace extracted by a SPME fiber. Finally, the extracted analytes on the fiber were desorbed and detected by GC/MS in electron impact (EI) mode. L-Valine, L-leucine, L-isoleucine, L-phenylanaline and L-tyrosine in blood samples were quantitatively analyzed by measurement of the corresponding N(O,S)-alkoxycarbonyl alkyl esters using an external standard method. SPME conditions were optimized, and the method was validated. The method was applied to diagnosis of neonatal phenylkenuria (PKU) and maple syrup urine disease (MSUD) by the analyses of five amino acids in blood samples. The results showed that the proposed method is a potentially powerful tool for simultaneous screening for neonatal PKU and MSUD.
Department of Chemistry, Fudan University, Shanghai 200433, P.R. China.
Chunhui
C
Deng
Ning
N
Li
Xiangmin
X
Zhang
D000596:Amino Acids / Q000097:blood* / Q000737:chemistry*; D005561:Formates / Q000737:chemistry*; D008401:Gas Chromatography-Mass Spectrometry / Q000379:methods*; D006801:Humans; D007231:Infant, Newborn / Q000097:blood*; D008375:Maple Syrup Urine Disease / Q000097:blood / Q000175:diagnosis; D008832:Microchemistry / Q000379:methods; D010661:Phenylketonurias / Q000097:blood / Q000175:diagnosis
D000596:Amino Acids; D005561:Formates; C039311:isobutyl chloroformate