1.Determination of 9 Amino Acid Endogenous Substances in Morning Urine of Depression Patients by LC-MS/MS
Hongyan SONG ; Jingsheng XIA ; Gangjian JI ; Zhangtao REN ; Xianglin ZHANG ; Fang LIU ; Ling CHEN
China Pharmacy 2020;31(1):91-98
ABSTRACT OBJECTIVE:To establish a method for the determination of 5-hydroxyindole acetic acid(5-HIAA),glutamine, hippurate,pimelate,proline,tryptophan,tyramine,tyrosine and valine in human urine. METHODS:Morning urine samples were collected from depression patients. The sample was extracted with acetonitrile after addition of internal standard cortisone. LC-MS/ MS method was adopted. The determination was performed on XTerra RP18 column with mobile phase consisted of 0.1% acetic acid-water as mobile phase A and 0.1% acetic acid-acetonitrile as mobile phase B(gradient elution). The column temperature was set at 40 ℃,and flow rate was 0.45 mL/min. Electrospray ion source(ESI)was used for quantitative analysis by multiple reaction monitoring (MRM). The precursor/product ion transitions (m/z) were monitored at m/z 192.2→146.1,m/z 147.2→130.0,m/z 180.1→105.1,m/z 161.1→125.2,m/z 116.1→70.2,m/z 205.2→188.2,m/z 138.2→121.1,m/z 182.0→123.0,m/z 118.2→72.1 and m/z 361.2→163.0(+ion-mode)for 5-HIAA,glutamine,hippurate,pimelate,proline,tryptophan,tyramine,tyrosine,valine and cortisone,respectively. RESULTS:The linear range of 5-HIAA,glutamine,pimelate,proline,tyramine and valine were 10.00-3 200 ng/mL(r=0.993 8-0.998 9,n=6). The lower limit of quantification was 10 ng/mL;the linear range of hippurate,tryptophan and tyrosine were 1 600-51 200 ng/mL(r=0.999 2-0.999 7,n=6). The lower limit of quantitation was 1 600 ng/mL. The results of accuracy tests were 86.29%-98.65%(n=6). RSDs of intra-day and inter-day precision tests were no more than 14.65%(n=6)CV of matrix effect were 6.18%-14.37%(n=6). Extraction recovery rates were 86.21%-98.14%(n=6). RE of stability tests were no more than 14.71%(n=3-6). CONCLUSIONS:The method is sensitive,accurate and suitable for the determination of 9 substances in human.