Tablet dosage forms flow analysis

El-gizawy reported the analysis of diloxanide furoate in its dosage forms by a HPLC method [40]. Furazol tablets containing 200 mg of metronidazole and 250 mg of diloxanide furoate were treated with 50 mL of methanol, sonicated for 10 minutes, and diluted to 100 mL with methanol. A portion of the resulting solution was centrifuged, and a 20 pL portion of the clear supernatant solution diluted to 10 mL with the mobile phase. This process yielded a final analyte concentration equivalent to 5 pg/mL. 20 pL aliquots of the solution were annualized by HPLC using a stainless steel column (10 cm x 4.6 mm) packed with Cyclobond I. The mobile phase consisted of 13 7 0.05 M phosphate buffer (pH 7) methanol (flow rate of 1 mL/min), and detection was performed at 254 nm. 

Panderi and Parissi-Poulou developed a microbore liquid chromatographic method for the simultaneous determination of benazepril hydrochloride and hydrochlorothiazide in pharmaceutical dosage forms [30]. The use of a BDS C-18 microbore analytical column was found to result in substantial reduction in solvent consumption and in increased sensitivity. The mobile phase consisted of a mixture of 25 mM sodium dihydrogen phosphate buffer (pH 4.8) and acetonitrile (11 9 v/v), pumped at a flow rate of 0.4 mL/min. Detection was effected at 250 nm using an ultraviolet absorbance detector. The intra- and inter-day relative standard deviation values were less than 1.25% (n = 5), while the relative percentage error was less than 0.9% (n = 5). The detection limits obtained according to the IUPAC definition were 0.88 and 0.58 pg/mL for benazepril hydrochloride and hydrochlorothiazide, respectively. The method was applied to the quality control of commercial tablets and content uniformity test, and proved to be suitable for rapid and reliable analysis. 

---