Effect of microwave radiation on redissolving precipitated matter in fluorouracil injection

The effect on the stability of fluorouracil injection of using microwave radiation to redissolve precipitated matter was studied. Fifteen ampuls each of Fluorouracil Injection, USP, containing precipitate were heated to 60 degrees C in a microwave oven and water bath, respectively. The contents of each heated ampul and of 15 control ampuls (unheated, no precipitate) were assayed by high-performance liquid chromatography, and the pH value of each sample was measured. Each test group fell within USP concentration requirements and showed no significant decrease in potency. Among the microwave-heated ampuls, a mean drop of 0.03 pH units was significant (p less than 0.05) but did not affect drug stability or solubility, since all samples remained within the USP pH range of 8.6-9.0. Precipitated matter in fluorouracil injection can be redissolved by heating with microwave radiation without significantly affecting the drug's stability.