Simultaneous Determination of 3 Kinds of Trace Organic Acids in Febuxostat by Headspace GC with Pre-column Derivatization

OBJECTIVE:To establish a method for the content determination of 3 kinds of trace organic acids in febuxostat,such as trifluoroacetic acid,formic acid and acetic acid.METHODS:GC method was adopted.The pre-column derivatization of organic acids was conducted with the mixture of methanol and H2SO4.Then the content of organic acid in 5 batches of samples were determined by headspace GC.The separation was performed on Supelcowax-10 capillary column with FID as the detector.The injection temperature was 160 ℃,the detector temperature was 260 ℃,with temperature programming.N2 was used as carrier gas and split ratio was 10:1.Vial equilibration temperature was 60 ℃ with equilibration time of 60 min.RESULTS:The baseline resolution was achieved between the derivatives of three organic acids.The linear ranges were 4.190～605.3 μg·mL-1,3.586～672.5 μg· mL-1,3.773～667.4 μg·mL-1(r≥0.999 0).The detective limits were 1.25,1.07 and 1.13 μg·mL-1 respectively.No organic acid was found in 5 batches of samples.CONCLUSION:The method is accurate and rapid,and can be used for effective separation and content determination of 3 trace organic acids in febuxostat.