Determination of diclofenac released from suppositories using UV spectrophotometry, spectra derivative spectrophotometry and HPLC.
Spectrophotometric method is often recommended in dissolution testing of not only tablets or capsules but also suppositories. Dissolution rate of diclofenac sodium was studied using a pharmacopoeial flow-through apparatus and pH 7.3 buffer. For two lipophilic suppository bases (Witepsol W-32 and H-19) dissolution rate was overestimated with the spectrophotometric zero-order method in comparison to HPLC method, although the difference was statistically significant only in the case of the Witepsol W-32 basis. On the other hand, first derivative spectrophotometry allowed for elimination of the interference of the suppository lipophilic components dissolved in the buffer medium and no difference was observed between the results of this analysis in comparison with HPLC results.
Sznitowska
Małgorzata
M
Departament of Pharmaceutical Technology, Medical University of Gdańsk, Hallera 107, 80-416 Gdańsk, Poland. msznito@amg.gda.pl
Stokrocka
Małgorzata
M
D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D004008:Diclofenac / Q000737:chemistry*; D012995:Solubility; D013056:Spectrophotometry, Ultraviolet / Q000379:methods*; D013488:Suppositories
D013488:Suppositories; D004008:Diclofenac