动态pH联接-扫集联用间接紫外法测定复方氨基酸注射液中酸性氨基酸含量

Determination of the acid amino acid in the Compound Amino Acid Injections with dynamic pH junction-sweeping combined with indirect UV detection method

目的检测复方氨基酸注射液中谷氨酸(Glu)和天冬氨酸(Asp)的含量。方法应用动态p H联接-扫集富集法联用间接紫外法。以10 mmol/L三羟甲基氨基甲烷、8 mmol/L苯甲酸和10 mmol/Lβ-环糊精组成的溶液为运行缓冲液(p H 7.5),3 mmol/L H_3PO_4溶液(p H 2.5)为样品基质。采用压力进样,进样压力和时间分别为1.0 psi和53 s。运行电压为12 kV。采用间接紫外检测法,以苯甲酸为紫外探针,检测波长为214 nm。结果复方氨基酸注射液中Glu和Asp的含量均在其标示量的95.9%～104.7%,均在2015年版《中国药典》规定的含量限度(95.0%～105.0%)范围内。结论动态p H联接-扫集联用间接紫外法可用于复方氨基酸注射液中酸性氨基酸的含量测定,所检测的复方氨基酸注射液中Glu和Asp含量符合规定。

Objective To detect the content of glutamic acid （Glu） and aspartic acid （Asp） in the Compound Amino Acid Injections. Methods Dynamic pH junction-sweeping in combination with indirect UV detection method was adopted. The running buffer （pH 7.5） consists of 10 mmol/L Tris, 8 mmol/L benzoic acid and 10 mmol/L β-cyclodextrin. The sample matrix was 3 mmol/L H3PO4 solution （pH 2.5）. Pressure was adopted for sample injection, and the sample injection pressure and time was 1.0 psi and 53 s, respectively. The applied voltage was 12 kV. Indirect UV detection using benzoic acid as UV probe was adopted. And the detection wavelength was set at 214 nm. Results The Glu and Asp in the Compound Amino Acid Injections were 95.9%-104.7% of their labeled amount, and the results agreed with the content limit range （95.0%-105.0%） in Chinese Pharmacopeia （2015 edition）. Conclusion Dynamic pH junction-sweeping combined with indirect UV detection method can be used to determine the content of acid amino acid in Compound Amino Acid Injections. And the contents of Glu and Asp in the Compound Amino Acid Injections are in accordance with the regulations.