hydrochlorothiazide

A simple, accurate and sensitive RP-HPLC method was developed and validated for the determination of candesartan cilexetil and hydrochlorothiazide in tablet dosage form. The separation of the two drugs was achieved on a Reprospher 100 –C l 8 column (250 x 4.6 mm, 5 µm particle size) with UV detection at 260 nm. The mobile phase consists of two solution, solution (1) orthophosphoric acid (pH 2.2) and the solution (2) which is acetonitrile and purified water in the ratio 55: 45 v/v, respectively. The method was validated in terms of linearity, accuracy, precision, specificity, limit of detection, limit of quantitation and robustness. Linearity was observed in the concentration range 10-70µg/ml for hydrochlorothiazide and 12.8 -89.6µg/ml for candesartan cilexetil. The limit of quantitation was found to be 8.58 and 4.6 µg/ml for hydrochlorothiazide and candesartan cilexetil, respectively whereas the limit of detection, was found to be 2.8 and 1.5 µg /ml for hydrochlorothiazide and candesartan cilexetil, respectively. The % recovery range of candesartan cilexetil was 97.84-101.62% and 100.9-101.53% for hydrochlorothiazide. Variation in HPLC conditions (flow rate, column temperature, mobile phase composition, and wavelength) were used to evaluate the robustness of the method. The method proved to be robust and still produces good results.

The present manuscript describe simple, sensitive, rapid, accurate, precise and economical first derivative spectrophotometric method for the simultaneous determination of nebivolol and hydrochlorothiazide in combined tablet dosage form. The derivative spectrophotometric method was based on the determination of both the drugs at their respective zero crossing point (ZCP). The first order derivative spectra were obtained in methanol and the determinations were made at 270.5 nm (ZCP of hydrochlorothiazide) for nebivolol and 282.5 nm (ZCP of nebivolol) for hydrochlorothiazide. The linearity was obtained in the concentration range of 5-100 μg/ml for nebivolol and 2-14 μg/ml for hydrochlorothiazide. The mean recovery was 100.04 + 0.93 and 99.87 + 1.16 for nebivolol and hydrochlorothiazide, respectively. The method was found to be simple, sensitive, accurate and precise and was applicable for the simultaneous determination of nebivolol and hydrochlorothiazide in pharmaceutical tablet dosage form. The results of analysis have been validated statistically and by recovery studies. Key words: Nebivolol, hydrochlorothiazide, recovery, first order derivative spectrophotometric method, tablet, validation.

  The present manuscript describe simple, sensitive, rapid, accurate, precise and economical first derivative spectrophotometric method for the simultaneous determination of nebivolol and hydrochlorothiazide in combined tablet dosage form. The derivative spectrophotometric method was based on the determination of both the drugs at their respective zero crossing point (ZCP). The first order derivative spectra were obtained in methanol and the determinations were made at 270.5 nm (ZCP of hydrochlorothiazide) for nebivolol and 282.5 nm (ZCP of nebivolol) for hydrochlorothiazide. The linearity was obtained in the concentration range of 5-100 μg/ml for nebivolol and 2-14 μg/ml for hydrochlorothiazide. The mean recovery was 100.04 + 0.93 and 99.87 + 1.16 for nebivolol and hydrochlorothiazide, respectively. The method was found to be simple, sensitive, accurate and precise and was applicable for the simultaneous determination of nebivolol and hydrochlorothiazide in pharmaceutical tablet dosage form. The results of analysis have been validated statistically and by recovery studies.     Key words: Nebivolol, hydrochlorothiazide, recovery, first order derivative spectrophotometric method, tablet, validation.