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Aim: A simple, rapid, selective, accurate, and precise UV spectrophotometric method has been developed for the estimation of ethacridine lactate from bulk and pharmaceutical formulation. Materials and Methods: Appropriate aliquot portions of stock standard solution of ethacridine lactate were transferred into five separate 10 ml volumetric flasks, and the volume was adjusted to the mark with double distilled water to obtain concentrations of 0.2, 0.4, 0.6, 0.8, 1.0, and 1.2 µg/ml. The λmax of ethacridine lactate in double distill water was found to be 271 nm with an apparent molar absorptivity of 59.781 x 10³ l/mol cm. The drug follows linearity in the concentration range 2-12 µg/ml with a correlation coefficient value of 0.998. Results: The proposed method was applied to pharmaceutical formulation and % amount of drug estimated 99.71% was found to be in good agreement with the label claim. The accuracy of the method was checked by recovery experiment performed at three different levels, i.e., 80%, 100%, and 120%. The % recovery was found to be in the range 99.26-100.25%. The low values of % RSD are indicative of the accuracy and reproducibility of the method. The precision of the method was studied as intraday, interday variations and repeatability. The % RSD value less than 2 indicates that the method is precise. Ruggedness of the proposed method was studied with the help of two analysts. Conclusion: The results indicated that the method could be used for the routine estimation of ethacridine lactate from tablet formulations. [ABSTRACT FROM AUTHOR]

The antioxidant activities of the methanol extracts from the wood and pericarp of Caesalpinia decapetala (Roth) Alston (Caesalpiniaceae) were assessed in efforts to validate the herb. The antioxidant activity of the plant has been studied using its ability to scavenger DPPH, superoxide radicals, and nitric oxide radical along with its ability to inhibit lipid peroxidation. The antioxidant activity and phenolic content of the pericarp as determined by the DPPH, superoxide radical, nitric oxide radical, total phenols, the flavonoids, and total flavonols were higher than that of the wood. Analysis of plant extracts revealed a high amount of polyphenols and flavonoids suggesting a possible role of these phytoconstituents in the antioxidant property. Moreover, the results were observed in a concentration and dose dependent manner. Studies clearly indicate that the C. decapetala has significant antioxidant activity. [ABSTRACT FROM AUTHOR]

Present work describes the potent antidiabetic fraction from flowers of Cassia auriculata Linn. Hydromethanolic extract along with its ethyl acetate and n-butanol fractions were evaluated for antidiabetic activity in alloxan-induced diabetes in rats. The n-butanol fraction exhibited significant reduction (p<0.001) in blood glucose levels and was also found effective in restoring the blood lipids and proteins to normal level. The activity was found comparable with standard drug phenformin. The hydromethanolic extract and its fractions were subjected to preliminary qualitative chemical investigations which indicated the presence of phenolic compounds, carbohydrates, tannins, steroids and amino acids. [ABSTRACT FROM AUTHOR]

Olmesartan medoxomil (OLME) belongs to a group of angiotensin II receptor blockers used as an antihypertensive agent and is currently being used for prevention of hypertension. This paper describes the validation and development of stability indicating RP-HPLC method for the determination of OLME in the presence of its degradation products generated from forced degradation study and characterization of degradation product (impurity). The assay involved gradient elution of OLME and an LC GC BDS C18 column (250 mmx4.5 mm, 5 μm particle size) was employed for loading the sample. The mobile phase A consisted of 7 ml triethylamine in 1000 ml water (pH adjusted to 3.0 with orthophosphoric acid) and B contained acetonitrile. Quantification was achieved with photodiode array detection at 257 nm. The chromatographic separation was obtained with a retention time of 6.72 min, and the method was linear in the range 50-150 µg/ml. The method was validated according to the ICH guidelines with respect to linearity, precision, accuracy, limit of detection (LOD), limit of quantification (LOQ), specificity and robustness. Impurity found in stressed and stability studies of olmesartan medoxomil in both drug substance and drug product are described. This degradation product is identified as 1-(biphenyl-4-ylmethyl)-1H-imidazole-5-carboxylic acid. An alkaline degradation pathway of Olmesartan Medoxomil, for the formation of this degradation product, has been proposed and the degradation product was characterized. [ABSTRACT FROM AUTHOR]

Forskolin is the first pharmaceutical drug and product derived from a plant to be approved in India by the DCGI in 2006. Forskolin (7beta-acetoxy-8, 13-epoxy-1a, 6β, 9a-trihydroxy-labd-14-en-11-one) is a diterpenoid isolated from plant Coleus forskohlii (Lamiaceae). It is a lipid-soluble compound that can penetrate cell membranes and stimulates the enzyme adenylate cyclase which, in turn, stimulates ciliary epithelium to activate cyclic adenosine monophosphate, which decreases intraocular pressure (IOP) by reducing aqueous humor inflow. The topical application of forskolin is capable of reducing IOP in rabbits, monkeys, and humans. In its drug interactions, forskolin may act synergistically with epinephrine, ephedrine and pseudoephedrine. Whereas the effects of anti-clotting medications like warfarin, clopidogre, aspirin, anoxaparin, etc., may be enhanced by forskolin. Forskolin is contraindicated in the medications for people with ulcers as forskolin may increase acid level. Forskolin has a very good shelf-life of five years. Recently, its Ophthalmic inserts and in situ gels for sustained and delayed-release drug delivery systems were tested in New Zealand Albino Rabbits for its antiglaucoma efficacy. This drug review explains Forskolin as a drug, its antiglaucoma potential and recent findings of forskolin as an antiglaucoma agent. The literature search method used for this review was different databases and search engines like PubMed, International Pharmaceutical Abstracts, Google, Medicinal and Aromatic Plants (MAPA). [ABSTRACT FROM AUTHOR]

Forskolin is the first pharmaceutical drug and product derived from a plant to be approved in India by the DCGI in 2006. Forskolin (7beta-acetoxy-8, 13-epoxy-1a, 6β, 9a-trihydroxy-labd-14-en-11-one) is a diterpenoid isolated from plant Coleus forskohlii (Lamiaceae). It is a lipid-soluble compound that can penetrate cell membranes and stimulates the enzyme adenylate cyclase which, in turn, stimulates ciliary epithelium to activate cyclic adenosine monophosphate, which decreases intraocular pressure (IOP) by reducing aqueous humor inflow. The topical application of forskolin is capable of reducing IOP in rabbits, monkeys, and humans. In its drug interactions, forskolin may act synergistically with epinephrine, ephedrine and pseudoephedrine. Whereas the effects of anti-clotting medications like warfarin, clopidogre, aspirin, anoxaparin, etc., may be enhanced by forskolin. Forskolin is contraindicated in the medications for people with ulcers as forskolin may increase acid level. Forskolin has a very good shelf-life of five years. Recently, its Ophthalmic inserts and in situ gels for sustained and delayed-release drug delivery systems were tested in New Zealand Albino Rabbits for its antiglaucoma efficacy. This drug review explains Forskolin as a drug, its antiglaucoma potential and recent findings of forskolin as an antiglaucoma agent. The literature search method used for this review was different databases and search engines like PubMed, International Pharmaceutical Abstracts, Google, Medicinal and Aromatic Plants (MAPA). [ABSTRACT FROM AUTHOR]

Abelmoschus manihot and Wrightia tinctoria, belonging to the botanical family Malvaceae and Apocynaceae, have been traditionally used by the locals in India for treatment of various ailments. The current study reports the outcome of acute oral toxicity investigation of Abelmoschus manihot and Wrightia tinctoria, on ICR mice. No mortalities or evidence of adverse effects have been observed in ICR mice following acute oral administration at the highest dose of 2500 mg/ kg crude extracts of Abelmoschus manihot and Wrightia tinctoria. This is the first report on the acute oral toxicity of Abelmoschus manihot and Wrightia tinctoria and the findings of this study are in agreement with those of in vitro experiments and thus provide scientific validation on the use of the leaves of Abelmoschus manihot and Wrightia tinctoria. [ABSTRACT FROM AUTHOR]

This paper describes the application of thin-layer chromatography ( TLC) combined with densitometry to simultaneous determination of levofloxacin hemihydrate ( LEV) and ambroxol hydrochloride ( AMB) in bulk and tablets. The separation was achieved on aluminum sheet of silica gel 60 F254 using chloroform: methanol: toluene: ammonia (10: 6: 3: 0.8 v/v/v/v) as mobile phase. Quantification was carried out densitometrically at 245 nm. This system was found to give compact spots for LEV ( Rf value of 0.4) and AMB ( Rf value of 0.7). The calibration curves for LEV and AMB was found to be linear between 9960–16600 ng/spot ( r2 = 0.999) and 600–1000 ng/spot ( r2 = 0.999), respectively. The mean percentage recoveries from tablets for LEV and AMB were 99.45% and 99.58%, respectively. The TLC-densitometry method has many advantages, such as simplicity, reasonable sensitivity, rapidity, and low cost, and it can be successfully used in routine analysis of both these drugs in tablet formulations. [ABSTRACT FROM AUTHOR]

Viscum angulatum Heyne ex DC (Viscaceae) is a leafless hemiparasitic shrub traditionally used in Asian countries for the treatment of hypertension. In the present study, the methanol extract of the whole plant was examined for diuretic activity in rats. The activity was evaluated using parameters such as urine volume after 5, 19, and 24 h and urine sodium, potassium, and chloride concentrations. The extract was further scrutinized for polyphenolic compounds and triterpenoids. The extract demonstrated a significant increase in and dose-dependent effect on urine excretion volume in comparison to the normal group in the tested range of 100–400 mg/kg. The extract demonstrated comparable saluretic and higher natriuretic activity (Na+/K+) compared to the furosemide treated group. However, the Cl−/Na+ + K+ ratio, which indicates carbonic anhydrase mediated activity, remained unaffected. HPLC and quantitative analysis of the extract revealed that polyphenolic compounds and the triterpenoid, oleanolic acid, are the major phytochemicals, and are proposed to be responsible for the observed diuretic effect. Oleanolic acid has been reported to possess diuretic activity with significant potassium loss in rats. In contrast to pure oleanolic acid, the extract demonstrated a valuable potassium-sparing effect. This suggests modulation of the diuretic effect of oleanolic acid by polyphenolics present in the extract. The observed dose-dependent potassium-sparing diuretic effect is a hereto unreported property of this plant. [ABSTRACT FROM AUTHOR]

The purpose of this research is to formulate and evaluate the suitability of pluronic lecithin organogels containing flurbiprofen for topical application. Four formulations were developed using flurbiprofen, lecithin, Pluronic F127, isopropyl palmitate, water, sorbic acid and potassium sorbate were coded as FL1, FL2, FL3 and FL4. All the formulations carried 30% w/w of lecithin phase and 70% w/w of Pluronic phase. The formulated organogels were evaluated for appearance and feel psychorheologically, in vitro diffusion study, drug content, viscosity and pH. Release of flurbiprofen from all formulations was monitored via dialysis membrane-70 and Wistar rat skin as a semipermeable membrane into phosphate buffer saline (0.2 M, pH 7.4) using Keshary-Chien diffusion cell. The viscosities of different formulations were determined by using Brookfield Viscometer at 25°. An attempt has been made to explore the potential of pluronic lecithin organogels for topical delivery of flurbiprofen. [ABSTRACT FROM AUTHOR]

A novel RP-HPLC method was developed and validated for the determination of compounds in an oral solution. The method describes the determination of domperidone along with sodium methylparaben, sodium propylparaben and sodium benzoate in liquid oral formulation. The chromatographic separations were performed using BDS Hypersil 5 µm C18 column and gradient elution (solvent A: phosphate buffer, pH 3.5 and solvent B: methanol) keeping a flow rate of 1.5 mL/min. Detection was done at dual wavelength (232 nm for domperidone and sodium benzoate, and 257 nm for sodium methylparaben and sodium propylparaben). Analysis time was <17 min. The retention times for domperidone, sodium benzoate, sodium methylparaben and sodium propylparaben were found to be 10.0, 6.5, 8.0, and 13.5 min, the calibration curves for domperidone, sodium benzoate, sodium methylparaben and sodium propylparaben were found to be linear in the range of 250-750, 50-150, 50-150, and 5-15 µg/mL, respectively. [ABSTRACT FROM AUTHOR]

A derivative UV spectrophotometric and a reversed phase high-performance liquid chromatographic method for determination of ciprofibrate in tablets was developed. The first-order derivative UV spectrophotometric method 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 C8 column with methanol:water (90:10, 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. [ABSTRACT FROM AUTHOR]

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 (10x10) 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 (Rf = 0.39±0.02) and metoprolol succinate (Rf = 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 r² = 0.9990±0.0013 with respect to peak area in the concentration range 400-1400 ng per spot for amlodipine besylate and r² = 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. [ABSTRACT FROM AUTHOR]

A dissolution method with high performance liquid chromatography (HPLC) analysis was validated for perindopril erbumine and indapamide in combination tablet formulation. The method was validated to meet requirements for a global regulatory filing and this validation included specificity, linearity, accuracy, precision, range, robustness and solution stability studies. The dissolution method, which uses a USP apparatus 1 with basket rotating at 100 rpm, 1000 ml of phosphate buffer, pH 6.8, as the dissolution medium, and reversed-phased HPLC was carried out at 50 °C on a 4.6 mmx250 mmx5 µm cyano column that contained USP packing L1 with acetonitrile:buffer 40:60 (v/v), pH 2.8, as mobile phase. UV detector was set at 225 nm. The method was found to be selective, linear, accurate and precise in the specified ranges. Intra-day and inter--day variability for method was <2% RSD. This method was successfully used for quantification of perindopril erbumine and indapamide combination tablet formulations. [ABSTRACT FROM AUTHOR]

A novel stability-indicating high-performance liquid chromatographic assay method was developed and validated for quantitative determination of ciprofibrate in bulk drugs and in pharmaceutical dosage form in the presence of degradation products. An isocratic, reversed phase HPLC method was developed to separate the drug from the degradation products, using an Ace5-C18 (250 mmx4.6 mm, 5 µm) advanced chromatography column, and methanol and water (90:10 v/v) as a mobile phase. The detection was carried out at a wavelength of 232 nm. The ciprofibrate was subjected to stress conditions of hydrolysis (acid and base), oxidation, photolysis and thermal degradation. Degradation was observed for ciprofibrate in base, in acid and in 30% H2O2. The drug was found to be stable in the other stress conditions attempted. The degradation products were well resolved from the main peak. The percentage recovery of ciprofibrate was from (98.65 to 100.01%) in the pharmaceutical dosage form. The developed method was validated with respect to linearity, accuracy (recovery), precision, system suitability, specificity and robustness. The forced degradation studies prove the stability indicating power of the method. [ABSTRACT FROM AUTHOR]

A stability-indicating RP-TLC/Densitometry method for analysis of Raloxifene hydrochloride both in bulk material and in tablets was developed and validated. Densitometric analysis of Raloxifene hydrochloride was carried out at 311 nm on TLC aluminium plates precoated with silica gel 60RP-18 F254S as the stationary phase and methanol :water : ammonia (95 : 05 : 0.1 v/v) as mobile phase. Raloxifene hydrochloride was well resolved at Rf 0.55 ± 0.02. The linear regression analysis data for the calibration plots showed good linear relationship with r² = 0.9969 ± 0.0015 with respect to peak area in the concentration range 100-600 ng per band. The mean value ± SD of slope and intercept was found to be 15.05 ± 0.44 and 201.9 ± 29.58 with respect to peak area. The limits of detection and quantification were 9.27 ng and 27.10 ng, respectively. Raloxifene hydrochloride was subjected to acid and alkali hydrolysis, oxidation, dry heat, and photodegradation. The drug underwent degradation under basic and oxidation conditions. This indicates that the drug is susceptible to alkali hydrolysis and oxidation. The proposed developed RPTLC/ Densitometry method can be applied for identification and quantitative determination of Raloxifene hydrochloride in bulk material and tablets. [ABSTRACT FROM AUTHOR]

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 (r²>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. [ABSTRACT FROM AUTHOR]

Introduction: Phyllanthus niruri, Andrographis paniculata and Embilica officinalis are most important and high value medicinal plant known for its hepatoprotective activity. Several analytical methods including HPTLC and HPLC are reported for respective phytoconstituents. However, there is no simultaneous estimation of phyllanthin and gallic acid reported. The Objective of present work is to develop and validate HPTLC method for simultaneous determination of phyllanthin and gallic acid in polyherbal hepatoprotective formulation. Method: The method is employed TLC alumina plates precoated with silica gel 60F-254 as a stationary phase and toluene: ethyl acetate: formic acid (5:3.5:0.5 v/v/v) as a mobile phase. The standard markers namely phyllanthin and galic acid were identified in polyherbal formulation containing P.niruri and E.officinalis by Rf value. Densitometric analysis of phyllanthin and gallic acid was carried out at 254nm. Results: The precision of method was confirmed by relative standard deviation (RSD) which was lower than the 2%. This method was found to give proper separation of phyllanthin and gallic acid. The linear regression data for calibration plot shown good relationship with r2=0.998 (phyllanthin) and 0.9991(Gallic acid) in the concentration range 5-9 μg/band. The method was validated for precision, accuracy, sensitivity, and specificity. Conclusion: statistical analysis proves that method is accurate and reproducible. The method is economical and can be employed for routine analysis of marketed polyherbal hepatoprotective formulation containing P.niruri and E.officinalis. [ABSTRACT FROM AUTHOR]

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 x 4.6 mm, 5 µm) column with a mobile phase consisting of methanol: water (60:40 v/v), pH adjusted to 2.8 with orthophosphoric acid and low 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 (r² = 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. [ABSTRACT FROM AUTHOR]

A simple, economic, selective, precise, and stability-indicating high-performance thin-layer chromatographic method for analysis of tamsulosin hydrochloride, both as a bulk drug and in formulations, was developed and validated according to ICH guidelines. The method employed HPTLC aluminiumplates precoated with silica gel 60F-254 as the stationary phase while the solvent system consisted of toluene : methanol : triethylamine (3.5 : 1.2 : 0.2v/v). The systemwas found to give compact spot for drug (Rf value of 0.52 ± 0.02). Densitometric analysis of tamsulosin was carried out in the absorbance mode at 280 nm. The linear regression analysis data for the calibration plots showed good linear relationship, r2 = 0.9982 ± 0.0012, with respect to peak area in the concentration range 400-2400 ng per spot. Themean value ± SD of slope and intercept were 2.6553±0.0173 and 777.7± 74.8with respect to peak area. The method was validated for precision, recovery, and robustness. The limits of detection and quantitation were 20.49 and 62.10 ng per spot, respectively. Tamsulosin was subjected to hydrolysis, oxidation, and thermal degradation which indicate the drug is susceptible to hydrolysis, oxidation, and heat. Statistical analysis proves that themethod is repeatable, selective, and accurate for the estimation of tamsulosin. [ABSTRACT FROM AUTHOR]

A series of nicotinyl 4-oxathieno[2,3-d]pyridine-2-ylmethyl esters, title compounds were synthesized. Compound IIIa was subjected to in vivo antihyperlipidemic activity in Wistar rats. The activity exhibited by synthesized compound was found to be less as compared to that produced by a standard, atorvastatin, administered in the form of suspension in 2% gum acacia. The activity was even lesser than that produced by the lead IIa. [ABSTRACT FROM AUTHOR]

Quinapril hydrochloride and hydrochlorothiazide were simultaneously determined by HPTLC in pharmaceutical formulations. The drugs were separated on silica gel 60 F254 plates using suitable combination of solvents as mobile phase. The validation parameters, tested in accordance with the requirements of ICH guidelines, prove the suitability of methods. [ABSTRACT FROM AUTHOR]

Two new, simple, accurate and economical spectrophotometric methods have been developed for simultaneous estimation of drotaverine hydrochloride and mefenamic acid in two-component tablet formulation. The methods employed are, first derivative spectrophotometry, using zero crossing technique and multicomponent analysis. Both the drugs obey the Beer's law in the concentration range employed for these methods. The results of analysis are validated by statistical evaluation and recovery studies. [ABSTRACT FROM AUTHOR]

A reverse phase high performance liquid chromatography method was developed for simultaneous estimation of paracetamol and valdecoxib in tablet formulation. The separation was achieved by Luna C18 column and methanol: phosphate buffer pH 3.5 (60:40 v/v) as eluent, at a flow rate of 1.0 ml/min. Detection was carried out at 242 nm. Etoricoxib was used as an internal standard. The retention time of PAR and VAL was found to be 3.01 and 8.51 min, respectively. The method was validated for linearity, accuracy and precision. Linearity for paracetamol and valdecoxib were in the range 25-150 µg/ml and 1-6 µg/ml, respectively. The developed method was found to be accurate, precise, and selective for simultaneous estimation of paracetamol and valdecoxib in tablets. [ABSTRACT FROM AUTHOR]

A reverse phase high performance liquid chromatography method was developed for simultaneous estimation of tizanidine HCl and valdecoxib in tablet formulation. The separation was achieved by Luna C18 column and acetonitrile: phosphate buffer pH 3.5 (50:50 v/v) as eluent, at a flow rate of 0.5 ml/min. Detection was carried out at 227 nm. Etoricoxib was used as an internal standard. The retention time of tizanidine and valdecoxib was found to be 4.43 and 16.60 min, respectively. The method was validated for linearity, accuracy and precision. Linearity for tizanidine and valdecoxib were in the range 0.4-2.0 µg/ml and 4-20 µg/ml, respectively. The developed method was found to be accurate, precise and selective for simultaneous estimation of tizanidine and valdecoxib in tablets. [ABSTRACT FROM AUTHOR]

A simple, accurate, economical and reproducible procedure for simultaneous estimation of atorvastatin calcium and ezetimibe in their tablet dosage form has been developed using, Q-absorbance equation. The method involves, the absorbance measurement at 235.5 nm (iso-absorptive point) and 246.0 nm (λmax of atorvastatin calcium), in methanol. Both the drugs, obey Beer-Lambert's law in the concentration range of 5-25 µg/ml. The results of analysis have been validated statistically and by recovery studies. [ABSTRACT FROM AUTHOR]