Stability-indicating method for simultaneous estimation of olmesartan medoxomile, amlodipine besylate and hydrochlorothiazide by RP-HPLC in tablet dosage form.

A simple, specific, accurate and precise stability-indicating reversed-phase high-performance liquid chromatographic method was developed for simultaneous estimation of olmesartan medoxomile (OLME), amlodipine besylate (AMLO) and hydrochlorothiazide (HCTZ) in tablet dosage form. The method was developed using an RP C18 base deactivated silica column (250 × 4.6 mm, 5 µm) with a mobile phase consisting of triethylamine (pH 3.0) adjusted with orthophosphoric acid (A) and acetonitrile (B), with a timed gradient program of T/%B: 0/30, 7/70, 8/30, 10/30 with a flow rate of 1.4 mL/min. Ultraviolet detection was used at 236 nm. The retention times for OLME, AMLO and HCTZ were found to be 6.72, 4.28 and 2.30, respectively. The proposed method was validated for precision, accuracy, linearity, range, robustness, ruggedness and force degradation study. The calibration curves of OLME, AMLO and HCTZ were linear over the range of 50-150, 12.5-37.5 and 31-93 µg/mL, respectively. The method was found to be sensitive. The limits of detection of OLME, AMLO and HCTZ were determined 0.19, 0.16 and 0.22 µg/mL and limits of quantification of OLME, AMLO and HCTZ were determined 0.57, 0.49 and 0.66, respectively. Forced degradation study was performed according to International Conference on Harmonization guidelines.

Development and Validation of HPTLC Method for Simultaneous Determination of Amlodipine Besylate and Metoprolol Succinate in Bulk and Tablets.

A simple, selective, precise high-performance thin-layer chromatographic method for simultaneous determination of amlodipine besylate and metoprolol succinate in bulk and pharmaceutical combined dosage form was developed and validated. The method employed HPTLC aluminum plates precoated with silica gel 60F-254 (10×10) as the stationary phase. The solvent system consisted of toluene:ethyl acetate:methanol:triethylamine (4:1:1:0.4 v/v/v). The system was found to give a compact spot for amlodipine besylate (R(f) = 0.39±0.02) and metoprolol succinate (R(f) = 0.59±0.02). Densitometric analysis of amlodipine besylate and metoprolol succinate was carried out in the absorbance mode at 254 nm. Linear regression analysis data for the calibration plots showed good linear relationship with r(2) = 0.9990±0.0013 with respect to peak area in the concentration range 400-1400 ng per spot for amlodipine besylate and r(2) = 0.9993±0.0013 with respect to peak area in the concentration range 3800-13300 ng per spot for metoprolol succinate. The method was validated for precision, recovery and robustness. The limits of detection and quantitation were 39.99 and 121.20 ng per spot for amlodipine besylate and 234.31 and 710.03 ng per spot for metoprolol succinate, respectively. Statistical analysis proved that the method is selective, precise and accurate for the estimation of amlodipine and metoprolol.

Quantitative Determination of Ciprofibrate in Tablets by Derivative UV Spectroscopy and RP-HPLC Method.

A derivative UV spectrophotometric and a reversed phase high-performance liquid chromatographic method for the determination of ciprofibrate in tablets was developed. The first-order derivative UV spectrophotometric method was found to be accurate with 100.57±0.97 recovery and precise with a coefficient of variation of 1.44. These results were compared to those obtained by reference methods, zero-order UV spectrophotometric method and a reversed-phase high-performance liquid chromatography method. A reversed-phase C(8) column with methanol:water (90:10, v/v, pH 3.7) mobile phase was used and the detector wavelength was set at 232 nm. Calibration solutions used in HPLC were ranging from 2 to 12 µg/ml. An ANOVA test (P = 0.0226, F = 4.935) showed that the results obtained with the derivative UV spectrophotometric method were comparable to those obtained using reference methods.

Development and validation of zero and first-order derivative area under curve spectrophotometric methods for the determination of entacapone in bulk material and in tablets.

AIM: The aim of this work is to establish two simple, economical, and rapid spectrophotometric methods for the quantification of entacapone in bulk material and in tablets. Further, this study is designed to validate the developed methods as per ICH guidelines. MATERIALS AND METHODS: In Methods I and II, a stock standard solution was prepared by dissolving 10 mg of entacapone in 100 mL of 10% v/v acetonitrile to obtain a concentration of 100 µg/mL. After suitable dilution, 10 µg/mL of entacapone was prepared and scanned in the UV-visible range 500-200 nm; entacapone showed a maximum absorbance at 384.40 nm. In Method I, area under curve (AUC) of the zero-order spectrum was recorded between 348.00 and 410.20 nm. While, in Method II, zero-order spectra were derivatized into first-order, and the AUC was recorded between 386.40 and 460.20 nm. For a linearity study, series of dilutions were prepared from stock solutions. RESULTS: In Method I, and II, entacapone followed linearity in the concentration range of 2-12 µg/mL and 5-30 µg/mL with (r(2)>0.999). The amounts of entacapone estimated by both these methods were found to be 99.24 ± 0.054 and 98.68 ± 1.04, respectively. CONCLUSION: The developed methods are simple, precise, rugged, robust, and economical. Both these methods can be used for routine analysis of entacapone from its tablet formulation.

Development and validation of RP-HPLC method for estimation of ethacridine lactate in bulk and in pharmaceutical formulation.

A new simple, precise, accurate and selective RP-HPLC method has been developed and validated for estimation of Ethacridine lactate in pharmaceutical formulation. The method was carried out on a Qualisil RP C-18 (250 mm × 4.6 mm, 5 µm) column with a mobile phase consisting of methanol: water (60:40 v/v), pH adjusted to 2.8 with ortho-phosphoric acid and flow rate of 1.0 mL/min. Detection was carried out at 271 nm. The retention time for ethacridine lactate was found to be 4.41 min. The ethacridine lactate followed linearity in the concentration range of 2- 12 µg/mL (r(2)= 0.9980). The amount of the drug estimated by proposed method was found to be in good agreement with label claim. The developed method was validated for sensitivity, accuracy, precision, ruggedness and robustness. The LOD and LOQ were found to be 0.11 and 0.33 µg. The proposed method can be used for routine analysis of ethacridine lactate in bulk drug and pharmaceutical formulation.

Stability-indicating HPTLC determination of ambroxol hydrochloride in bulk drug and pharmaceutical dosage form.

A simple, selective, precise, and stability-indicating high-performance thin-layer chromatographic (HPTLC) method for the analysis of ambroxol hydrochloride both as a bulk drug and in formulations was developed and validated. The method employed HPTLC aluminium plates precoated with silica gel 60F-254 as the stationary phase. The solvent system consisted of methanol-triethylamine (4:6 v/v). The system was found to give a compact spot for ambroxol hydrochloride (R(f) value of 0.53 +/- 0.02). Densitometric analysis of ambroxol hydrochloride was carried out in the absorbance mode at 254 nm. The linear regression analysis data for the calibration plots showed good linear relationship with r(2) = 0.9966 +/- 0.0013 with respect to peak area in the concentration range 100-1000 ng/spot. The mean value +/- standard deviation of slope and intercept were 164.85 +/- 0.72 and 1168.3 +/- 8.26 with respect to peak area. The method was validated for precision, recovery, and robustness. The limits of detection and quantitation were 10 and 30 ng/spot, respectively. Ambroxol hydrochloride was subjected to oxidation and thermal degradation. The drug undergoes degradation under oxidation and heat conditions. This indicates that the drug is susceptible to oxidation and heat. Statistical analysis proves that the method is repeatable, selective, and accurate for the estimation of said drug. Stability indicating of new chemical entities is an important part for the drug development of ambroxol hydrochloride and for its estimation in plasma and other biological fluids; the novel Statistical analysis proves that the method is repeatable and selective for the analysis of ambroxol hydrochloride as bulk drug and in pharmaceutical formulations. The proposed developed HPTLC method can be applied for identification and quantitative determination of ambroxol hydrochloride in bulk drug and dosage forms. This work is to determine the purity of the drug available from the various sources by detecting the related impurities.

Incidence of hypertension in Ahmadu Bello University Hospital Kaduna--Nigeria.

The incidence and pattern of hypertension in General Out Patient Department of Ahmadu Nello University Teaching Hospital, Kaduna have been described. Two thousand nine hundred and fifty adult patients with 1,636 males and 1,314 females, aged 20 to 70 years were examined in this study. One hundred and twelve patients (3.79%) with 47 males (2.87%) and 65 females (4.94%) were found to be suffering from hypertension. The incidence in females was significantly more than in males. The mode of presentation of 112 cases with hypertension has been discussed. Thirty four (30.35%) with 14 males and 20 females were asymptomatic. Sixteen (14.28%) with 7 males and 9 females presented with cardiac failure. Contrary to previous opinion this study has shown that hypertension is probably more common in Northern Nigeria than was previously realized. There appears to be ample justification for further and more detailed study of hypertension in the rural and urban communities in this area.