Validation The method of measuring the amount of clindamycin in the liposomal formulation

Clindamycin is prescribed to treat the different infections but in some cases, it does not have any medical effect because of different resistance mechanisms in bacteria. A method to counter the resistant bacteria is to use liposomal formulation. Making liposomal formulation needs to measure the content of injected drug into liposome. In this study, a method was proposed to measure the content of clindamycin in liposomal formulation. Criteria of verification based on ICH Q2B protocol included linearity, accuracy, precision, selectivity, sensitivity of diagnosis and determination limits. Initially, each sample was solved in methanol and 0.1M soda with 8:1 and then intensity of attraction for each sample was measured with 201 nm wavelength by UV spectrophotometer. It was possible to draw the calibration curve for clindamycin in range of 0.2 to 8.1 mg/ml with correlation coefficient of 0.999 by this mechanism. This study showed that liposomal formulation obtained by phospholipid (% 2.6), cholesterol (%0.8) and clindamycin (%0.1) and diluted with methanol for 50 times does not have any attraction in 201 nm. Therefore, it is possible to measure the concentration of clindamycin without molecules forming liposome. The capacity of reproducing clindamycin in range of 0.80 and 0.120 is 80% and 83% respectively. The standard deviation for intra- and inter-day precision is lower than 4% and diagnosis and determination limits are 0.43 and 0.131 mg/ml respectively. The result showed that this method can be suitable to measure the content of clindamycin in liposomal formulation.