Determination of Five Residual Organic Solvents in Thymalfasin by GC

OBJECTIVE To develop a GC method for the determination of five residual organic solvents in thymalfasin. METHODS The five residual organic solvents were determined by GC with FID detector, on DB-624 capillary GC column, with n-butyl alcohol as internal standard. RESULTS The five residual organic solvents were completely separated (R>2.0), and theoretical plate numbers were all above 10 000. Thymalfasin sample had no interference with the detection of the five residual organic solvents. The method had a good linearity and the liner range of methanol, acetonitrile, dichloromethane, pyridine and DMF were 30-480 μg·mL^-1(r=0.999 8), 4.1-65.6 μg·mL^-1(r=0.999 9), 6.0-96 μg·mL^-1(r=0.999 2), 2.0-32.0 μg·mL^-1(r=0.999 3), 8.8-141 μg·mL^-1(r=0.999 9), respectively. The recoveries (n=9) of above five organic solvents were 99.6%, 100.8%, 99.8%, 100.8%, 99.0%, respectively. CONCLUSION The method is simple, sensitive, and accurate with good durability. It can be used for the determination of the five residual organic solvents in thymalfasin.