Table 1. The linear equation, range and correlation coefficient of 18 kinds of AAs.

Amino acids	Linear equation	Linear range (µmol/mL)	Correlation coefficient
Asp	y=9.434x-0.141	0.0862-0.862	0.9987
Glu	y=9.033x-0.117	0.0850-0.850	0.9978
Ser	y=13.713x+0.114	0.1152-1.152	0.9992
Gly	y=12.015x-0.099	0.2073-2.073	0.9995
His	y=11.969x+0.094	0.0900-0.900	0.9979
Arg	y=12.432x-0.246	0.1078-1.078	0.9957
Thr	y=12.769x-1.037	0.1576-1.576	0.9968
Ala	y=11.152x-0.106	0.1138-1.138	0.9990
Pro	y=11.476x+0.176	0.1158-1.158	0.9993
Tyr	y=11.180x+0.008	0.0628-0.628	0.9968
Val	y=17.585x+0.013	0.0736-0.736	0.9995
Met	y=11.251x-0.002	0.0625-0.625	0.9997
Cys	y=7.0880x-0.001	0.1169-1.169	0.9999
Iso	y=11.853x+0.014	0.1008-1.008	0.9992
Leu	y=11.639x+0.003	0.0825-0.825	0.9991
Phe	y=17.342x-0.236	0.0642-0.642	0.9999
Trp	y=14.392x-0.072	0.0562-0.562	0.9999
Lys	y=22.350x+0.027	0.0741-0.741	0.9996