Pharmacopoeia Method Research Articles

Antivenom Evaluation by Electrophysiological Analysis.

Scorpion stings on humans are medically relevant because they may contain toxins that specifically target ion channels. During antivenom production, pharmaceutical companies must use a large number of experimental animals to ensure the antivenom’s efficacy according to pharmacopeia methods. Here we present an electrophysiological alternative for the evaluation of horse antivenoms produced against two species of Moroccan scorpions: Buthus mardochei and Androctonus mauretanicus. Human sodium and potassium channels and acetylcholine nicotinic receptors were analyzed by standard patch-clamp techniques. The results showed that the antivenom is capable of reversing ion current disruption caused by the venom application. We propose the use of this in vitro technique for antivenom evaluation as an alternative to using a large number of live animals.

Using the fundamentals of adsorption to understand peak distortion due to strong solvent effect in hydrophilic interaction chromatography

The peak distortion observed in hydrophilic interaction chromatography (HILIC) may be caused by the sample diluent to mobile phase mismatch. The United States Pharmacopeia (USP) method for organic impurities in cetirizine HCl tablets calls for such a mismatch, having a higher concentration of strong solvent in the sample diluent than in the mobile phase. A significant peak deformation is reported for cetirizine (a second-generation antihistamine) when it is purified on a Ethylene Bridged Hybrid (BEH) HILIC column (4.6mm×100mm, 2.5μm particles) using an acetonitrile–water eluent mixture and a sample diluent containing 7% and 9% water (in volume), respectively. The mechanism and physical origin of such peak distortion are related to (1) the diluent-to-eluent excess of water that propagates along the column at a velocity similar to that of the analyte, (2) the significant drop of the Henry's constant of the analyte upon increasing water concentration in the eluent, (3) the sample volume injected, and (4) to the pre-column sample dilution factor that depends on the characteristics of the LC instrument used.This proposed mechanism is validated from the calculation of the concentration profiles of cetirizine and water by using the equilibrium-dispersive (ED) model of chromatography. The observed distortion of cetirizine peaks is successfully predicted from the measurement of (1) the excess adsorption isotherm of water from acetonitrile onto the BEH HILIC adsorbent, (2) the retention factor of cetirizine as a function of the volume fraction (7, 8, and 9%) of water in the mobile phase, and (3) of the pre-column sample dispersion related to the instrument used (HPLC or UHPLC). The results of the calculations enables the user to anticipate the impacts of the diluent-to-eluent mismatch in water content, the injection volume, the analyte retention under infinite dilution, and of the pre-column sample dispersion on the amplitude of peak distortion in HILIC. Appropriate and permitted alterations of the USP method are then suggested based on a sound physico-chemical approach.

Development and evaluation of a PCR-based assay kit for authentication of Zaocys dhumnades in traditional Chinese medicine

We developed a kind of Zaocys dhumnades DNA test kit and it’s indexes including specificity, sensitivity and stability were evaluated and compared with the method recorded in Chinese Pharmacopoeia (2010 edition). The bioinformatics technology was used to design primers, sequencing and blast, in conjunction with PCR technology based on the characteristics of Z. dhumnades cytochrome b (Cyt b) gene. The efficiency of nucleic acid extraction by the kit was done in accordance with Pharmacopoeia method. The kit stability results proved effective after repeated freezing and thawing 20 times. The sensitivity results indicated that the lowest amount detected by the kit was 0. 025 g of each specimen. The specificity test of the kit was 100% specific. All repeatability tests indicated the same results when conducted three times. Compared with the method recorded in Chinese Pharmacopoeia, the PCR-based assay kit by our team developed is accurate, effective in identification of Z. dhumnades, it is simple and fast, demonstrating a broad prospect in quality inspection of Z. dhumnades in the future.

Renewal of an old European Pharmacopoeia method for Terazosin using modeling with mass spectrometric peak tracking

An older method for terazosin was reworked in order to reduce the analysis time from 90min (2×45min) to below 5min. The method in European Pharmacopoeia (Ph.Eur.) investigates the specified impurities separately. The reason of the different methods is that the retention of two impurities is not adequate in reversed phase, not even with 100% water. Therefore ion-pair-chromatography has to be applied and since that two impurities absorb at low UV-wavelength they had to be analyzed by different method than the other specified impurities. In our new method we could improve the retention with pH elevation using a new type of stationary phases available for high pH applications. Also a detection wavelength could be selected that is appropriate for the detection and quantification of all impurities.The method development is the bottleneck of liquid chromatography even today, when more and more fast chromatographic systems are used. Expert knowledge with intelligent programs is available to reduce the time of method development and offer extra information about the robustness of the separation. Design of Experiments (DoE) for simultaneous optimization of gradient time (tG), temperature (T) and ternary eluent composition (tC) requires 12 experiments. A good alternative way to identify a certain peak in different chromatograms is the molecular mass of the compound, due to its high specificity. Liquid Chromatography–Mass Spectrometry (LC–MS) is now a routine technique and increasingly available in laboratories. In our experiment for the resolution- and retention modeling the DryLab4 method development software (Version 4.2) was used. In recent versions of the software the use of (m/z)-MS-data is possible along the UV-peak-area-tracking technology. The modelled and measured chromatograms showed excellent correlations. The average retention time deviations were ca. 0.5s and there was no difference between the predicted and measured Rs,crit −values.

Development of Intramammary Drug Delivery Systems: Novel In Vitro Release Method

The aim of this study was to develop an in vitro release model for intramammary drug delivery system (IMDS) evaluation. This study was the first to establish an in vitro–in vivo correlation with investigation of an IMDS containing lasalocid. Three different methods including the standard United States Pharmacopeia dissolution method with apparatus 2, a modified United States Pharmacopeia method using a dialysis bag, or a specifically designed enhancer cell system, were assessed for the release study. Full cream milk and water were selected as the release media. In vivo evaluation was carried out by administering lasalocid IMDS into the udder of lactating Holstein dairy cows. Milk samples were collected and analyzed at selected time points after treatment. Dissolution data were fitted to various kinetic models. The results indicated that the release rate of lasalocid from IMDS was controlled by factors other than diffusion, which could include the sedimentation of lasalocid to the interface and the wetting of lasalocid particles by water at the interface of oil in the formulation and release media. The results obtained in vivo and in vitro were consistent. The in vitro assessment supports formulation design for early stage development and potentially for in vivo performance analysis.

Analysis of isoquinoline alkaloids using chitosan-assisted liquid-solid extraction followed by microemulsion liquid chromatography employing a sub-2-micron particle stationary phase.

A simple, efficient, and green chitosan-assisted liquid-solid extraction method was developed for the sample preparation of isoquinoline derivative alkaloids followed by microemulsion LC. The optimized mobile phase consisted of 0.8% w/v of ethyl acetate, 1.0% w/v of SDS, 8.0% w/v of n-butanol, 0.1% v/v acetic acid, and 10% v/v ACN. Compared to pharmacopoeia method and organic solvent extraction, this new approach avoided the use of volatile organic solvents, replacing them with relatively small amounts of chitosan. Under the optimum conditions, good linearity (r2 > 0.9980) for all calibration curves and low detection limits between 0.05 and 0.10 μg/mL were achieved. The presented procedure was successfully applied to determine alkaloids in Rhizoma coptidis with satisfactory recoveries (81.3-106.4%).

Development of Conductivity Method as an Alternative to Titration for Hydrolytic Resistance Testing Used for Evaluation of Glass Vials Used in Pharmaceutical Industry.

The quality of glass vials used as primary containers in the pharmaceutical industry is of concern due to recent observations of glass flake-like delamination, or lamellae, under specific storage conditions. The current European Pharmacopoeia method to assess glass vial quality utilizes acid titration of vial extract pools to determine hydrolytic resistance or alkalinity. As an alternative to the European Pharmacopoeia method, the vial extracts were analyzed for conductivity, which directly determines the level of ions that were readily extracted from the vial surfaces. Lower quality glass would have greater surface defects that lead to higher ions extracted and higher conductivity value. The conductivity method was found to be suitable to measure the ions in water extracts and showed strong correlation with alkalinity. The advantage of the conductivity method over the alkalinity method was greater ease, lower volume requirements, stability, and flexibility in analysis.

Influence of dry herbal extracts on pentylenetetrazole-induced seizures in mice: screening results and relationship “chemical composition – pharmacological effect”

Aim. Screening of 48 dry extracts of plants belonging to 18 species of 8 families not studied before on anticonvulsant activity, to analyze the chemical composition for the extracts with proved anti- and proconvulsant activity, and to estimate the connection of the effect of herbal products and their phytochemical composition.Methods. On the model of pentylenetetrazole-induced seizures in mice the influence of 48 dry herbal extracts with varied chemical composition has been investigated. Extracts were standardized by the content of alkaloids, flavonoids and polyphenols according to European Pharmacopoeia methods (HPTLC, HPLC, UPLC, GC-MS).Results. By the integral indicator of efficacy – reduction of the mortality rate – it has been found that 11 of herbal preparations have significant anticonvulsant properties, 10 extracts act as proconvulsants, and the remaining 27 extracts have practically no effect on experimental convulsions. It has been established that there is a relationship between the pharmacological effect of preparations and phytochemical composition of the plant being extracted as well as the host species (for parasitic species – Viscum album) and the degree of polarity of the extracting agents. For the extracts with expressed anti- and proconvulsant features the chemical composition has been investigated.Conclusion. The detailed analysis of relationship between phytochemical composition and influence of the extracts on the experimental seizures has found that anticonvulsant peculiarities of extracts most probably depend on rutin high content, but for the herbal medicines with proved proconvulsant properties the role of individual biologically active compounds has not been defined

Toxic Constituents Index: A Toxicity-Calibrated Quantitative Evaluation Approach for the Precise Toxicity Prediction of the Hypertoxic Phytomedicine-Aconite.

Complex chemical composition is an important reason for restricting herbal quality evaluation. Despite the multi-components determination method significantly promoted the progress of herbal quality evaluation, however, which mainly concerned the total amount of multiple components and ignored the activity variation between each one, and did not accurately reflect the biological activity of botanical medicines. In this manuscript, we proposed a toxicity calibrated contents determination method for hyper toxic aconite, called toxic constituents index (TCI). Initially, we determined the minimum lethal dose value of mesaconitine (MA), aconitine (AC), and hypaconitine (HA), and established the equation TCI = 100 × (0.3387 ×XMA + 0.4778 ×XAC + 0.1835 ×XHA). Then, 10 batches of aconite were selected and their evaluation results of toxic potency (TP), diester diterpenoid alkaloids (DDAs), and TCI were compared. Linear regression analysis result suggested that the relevance between TCI and TP was the highest and the correlation coefficient R was 0.954. Prediction error values study also indicated that the evaluation results of TCI was highly consistent with that of TP. Moreover, TCI and DDAs were both applied to evaluate 14 batches of aconite samples oriented different origins; from the different evaluation results, we found when the proportion of HA was reached 25% in DDAs, the pharmacopeia method could generate false positive results. All these results testified the accuracy and universality of TCI method. We believe that this study method is rather accurate, simple, and easy operation and it will be of great utility in studies of other foods and herbs.

Improvement of powder flowability and hygroscopicity of traditional Chinese medicine extract by surface coating modification technology

To study the improvement of powder flowability and hygroscopicity of traditional Chinese medicine extract by surface coating modification technology. The 1% hydrophobic silica nanoparticles were used as surface modifier, and andrographis extract powder was taken as a model drug. Three different techniques were used for coating model drugs, with angle of repose, compressibility, flat angle and cohesion as the comprehensive evaluation indexes for the powder flowability. The powder particle size and the size distribution were measured by Mastersizer 2000. FEI scanning electron microscope was used to observe the surface morphology and structure of the powder. The percentage of Si element on the powder surface was measured by energy dispersive spectrometer. The hygroscopicity of powder was determined by Chinese pharmacopoeia method. All of the three techniques can improve the flowability of powder extract. In particular, hygroscopicity of extract powder can also be improved by dispersion and then high-speed mixing, which can produce a higher percentage of Si element on the powder surface. The improvement principle may be correlated with a modifier adhered to the powder surface.

Pediatric Dispersible Tablets: a Modular Approach for Rapid Prototyping.

The design of pediatric formulations is challenging. Solid dosage forms for children have to meet the needs of different ages, e.g. high number of dosing increments and strengths. A modular formulation strategy offering the possibility of rapid prototyping was applied. Different tablet compositions and the resulting tablet characteristics were investigated for dispersible tablets using customized analytical methods. Fluid bed granules were blended with extragranular components, and compressed to tablets. Disintegration behavior was studied with a Texture Analyzer and a Tensiometer. Methods for determination of disintegration time and water uptake of tablets were developed with a Texture Analyzer, and a Tensiometer, respectively. Twenty-two different tablet formulations were prepared and analyzed with respect to disintegration time, hardness, friability, and viscosity. Multivariate data analysis revealed a high impact of type and amount of viscosity enhancer on the disintegration behavior of tablets. An optimized formulation was selected with a disintegration time of 24s. Methods providing additional information on the disintegration behavior of dispersible tablets compared to standard pharmacopoeia methods were established. Selecting the right type and level of viscosity enhancer and superdisintegrant was critical for developing pediatric tablets with a disintegration time of less than 30s but still pleasant mouth feel.

Development of a Suitable Dissolution Method for the Combined Tablet Formulation of Atorvastatin and Ezetimibe by RP-LC Method.

Pharmaceutical preparations of ezetimibe and atorvastatin are generally used to regulate the lipid level in blood. It decreases the secondary events for patients with high cholesterol and clinical cardiovascular disease such as non-fatal or fatal heart attack. There is no any pharmacopoeia method available for the dissolution testing recommended by the FDA. Development of dissolution tests method is very critical parameter especially for the pharmaceutical preparations that contain Class II drugs (slightly soluble, good permeable). In the proposed method, the effects of pH and surfactant on the dissolution of poorly water soluble combined drug therapy with a different pKa values in an in vitro environment is investigated. The content of our study was designed to answer these open-ended questions. The optimized test conditions achieved under sink conditions with USP apparatus 2 at a paddle rotation speed of 75 rpm and 900 ml in 0.01 M Acetate buffer (pH= 6.8) containing 0.45% SDS as a dissolution medium. Quantification of dissolution samples were analyzed with a new fully validated RP-LC method with UV detection at 242 nm.

Development of Two Charge-Transfer Complex Spectrophotometric Methods for Determination of Tofisopam in Tablet Dosage Form

Purpose: To develop an easy, fast and sensible spectrophotometric method for determination of tofisopam in tablet dosage form. Methods: Tofisopam as n-electron donor is react with two π-acceptors namely: chloranilic acid (ChA), and 7,7,8,8 tetracyanoquinodimethane (TCNQ) to form charge-transfer complexes. The obtained complexes were tested spectrophotometrically at 520 and 824 nm for ChA and TCNQ, respectively. The optimal conditions affecting the reaction status were surveyed and optimized, and the results compared with Japanese Pharmacopeia method. Results: The calibration curve were obeyed Beer`s low in the ranges 25 – 125 and 30 – 150 μg/mL for ChA and TCNQ, respectively. The lower limit of detection was 8.0 and 10.0 μg/m for ChA and TCNQ, respectively. The slope and intercept of the calibration graphs were 0.0025 and 0.011, and 0.0115 and -0.237 for ChA and TCNQ, respectively Conclusion: The proposed methods have successfully been applied to determination of tofisopam with good accuracy and precision. The methods are accurate as the Japanese pharmacopeial method amd may be applied for routine analysis in quality control laboratories. Keywords: Charge-transfer complex, Tofisopam, Chloranilic acid, Tetracyanoquinodimethane, Spectrophotometry

Toward Biopredictive Dissolution for Enteric Coated Dosage Forms.

The aim of this work was to develop a phosphate buffer based dissolution method for enteric-coated formulations with improved biopredictivity for fasted conditions. Two commercially available enteric-coated aspirin products were used as model formulations (Aspirin Protect 300 mg, and Walgreens Aspirin 325 mg). The disintegration performance of these products in a physiological 8 mM pH 6.5 bicarbonate buffer (representing the conditions in the proximal small intestine) was used as a standard to optimize the employed phosphate buffer molarity. To account for the fact that a pH and buffer molarity gradient exists along the small intestine, the introduction of such a gradient was proposed for products with prolonged lag times (when it leads to a release lower than 75% in the first hour post acid stage) in the proposed buffer. This would allow the method also to predict the performance of later-disintegrating products. Dissolution performance using the accordingly developed method was compared to that observed when using two well-established dissolution methods: the United States Pharmacopeia (USP) method and blank fasted state simulated intestinal fluid (FaSSIF). The resulting dissolution profiles were convoluted using GastroPlus software to obtain predicted pharmacokinetic profiles. A pharmacokinetic study on healthy human volunteers was performed to evaluate the predictions made by the different dissolution setups. The novel method provided the best prediction, by a relatively wide margin, for the difference between the lag times of the two tested formulations, indicating its being able to predict the post gastric emptying onset of drug release with reasonable accuracy. Both the new and the blank FaSSIF methods showed potential for establishing in vitro-in vivo correlation (IVIVC) concerning the prediction of Cmax and AUC0-24 (prediction errors not more than 20%). However, these predictions are strongly affected by the highly variable first pass metabolism necessitating the evaluation of an absorption rate metric that is more independent of the first-pass effect. The Cmax/AUC0-24 ratio was selected for this purpose. Regarding this metric's predictions, the new method provided very good prediction of the two products' performances relative to each other (only 1.05% prediction error in this regard), while its predictions for the individual products' values in absolute terms were borderline, narrowly missing the regulatory 20% prediction error limits (21.51% for Aspirin Protect and 22.58% for Walgreens Aspirin). The blank FaSSIF-based method provided good Cmax/AUC0-24 ratio prediction, in absolute terms, for Aspirin Protect (9.05% prediction error), but its prediction for Walgreens Aspirin (33.97% prediction error) was overwhelmingly poor. Thus it gave practically the same average but much higher maximum prediction errors compared to the new method, and it was strongly overdiscriminating as for predicting their performances relative to one another. The USP method, despite not being overdiscriminating, provided poor predictions of the individual products' Cmax/AUC0-24 ratios. This indicates that, overall, the new method is of improved biopredictivity compared to established methods.

Characterization and determination of isomers in plants using trace matrix solid phase dispersion via ultrahigh performance liquid chromatography coupled with an ultraviolet detector and quadrupole time-of-flight tandem mass spectrometry

Here, a novel β-cyclodextrin (β-CD) based trace matrix solid-phase dispersion (MSPD) method was developed to extract isomers from different honeysuckle samples using ultrahigh performance liquid chromatography. The structures of the analytes were characterized and determined via quadrupole time-of-flight tandem mass spectrometry and nuclear magnetic resonance. Under optimum conditions, 25mg of sample was dispersed with 75mg of β-CD, and 0.5mL of methanol was used as the elution solvent. The proposed method produced a good linearity (r2>0.99) for the isomers, with limits of detection ranging from 1.62 to 3.33ng/mL. The average recovery values that were obtained from analyzing the spiked samples were calculated to be in the range of 87.04–105.20%. Moreover, the trace MSPD method required less reagents and a shorter extraction time in comparison with the traditional pharmacopoeia method and other reported approaches. The developed method was successfully applied for the determination of three real honeysuckle samples that were collected from different cultivated areas.

Dacarbazine.

Dacarbazine is a cell cycle nonspecific antineoplastic alkylating agent used in the treatment of metastatic malignant melanoma. This chapter contains the descriptions of the drug: nomenclature, formulae, chemical structure, elemental composition, and appearance. The uses and applications of dacarbazine and the methods that were used for its preparation are reported. The methods which were used for the physical characterization of the drug are ionization constant, solubility, X-ray powder diffraction pattern, crystal structure, melting point, and differential scanning calorimetry. The profile contains the spectra of the drug: ultraviolet spectrum, vibrational spectrum, nuclear magnetic resonance spectra, and mass spectrum. The compendial methods of analysis for dacarbazine include the United States Pharmacopeia methods, British Pharmacopeia methods, and International Pharmacopeia methods. Other reported methods that are used for the analysis of the drug are high-performance liquid chromatography, high-performance liquid chromatography-mass spectrometry, and polarography. Metabolism, pharmacokinetics, and stability studies on dacarbazine are also included. Reviews of some analytical methods and physicochemical properties of the drug as well as the most important enzymes that are involved in the prodrug activation are provided. Sixty-four references are listed at the end of this monograph.

Comparison of Two Pharmacopoeia Methods for Determining Higher Molecular Weight Proteins in Insulin Glargine

Objective: We compared two pharmacopoeia methods, European Pharmacopoeia (EP) and Indian Pharmacopoeia (IP),with respect to their key char­acteristics for determining higher molecular weight proteins (HMWP) in insulin glargine. These methods differ in the mobile phase composition, number of HPLC columns used and run time. Material and Methods: Testing was carried out exactly as described in the respective pharmaco­poeia methods. Results: Our results indicate that both methods provide insulin glargine peak with comparable symmetry factor. Results obtained with two methods are precise in terms of intra-assay variation; however, inter-assay variation was better with IP method. Also, both methods provide similar results in terms of estimation of HMWP content in insulin glargine. Conclusion: Based on the findings we propose that IP method may replace EP method for determination of HMWP content in insulin glargine which will reduce the analysis time and running cost of the test without compromising with the results. Key words: HMWP, Insulin glargine, Monomer, Pharmacopoeia, Size exclusion HPLC.

In vitro evaluation of the quality control parameters of six brands of sustained release nifedipine tablets

An in vitro evaluation of the quality control parameters of six brands of sustained release nifedipine tablets (coded NIF-A __ NIF-F) was conducted to ascertain their pharmacopoeia compliance. Their respective manufacture and expiry dates, product registration status, country of origin as well as label claim of potency were noted. Total drug contents of respective samples were determined with the high performance liquid chromatography (HPLC). Tablet weight, hardness, disintegration and friability were assessed using the British Pharmacopoeia methods. The dissolution profile was determined using USP Apparatus 2 at 50 rpm and 37±0.5˚C in 900 ml of phosphate buffer for 8 h. A 5 mL of sample was withdrawn at hourly intervals and analyzed using UV spectrophotometer at 275 nm. Results show that physical parameters of the respective brands of nifedipine tablets studied were within pharmacopeia acceptable limits. Total drug content for all the samples fell within the USP requirement of 90- 110 %. The dissolution requirements for nifedipine extended release tablets are specified in the United States Pharmacopoeia. The fraction of drug dissolved using the USP apparatus at 50 rpm is specified for nifedipne ER tablets as 10 – 30 % ( 2- 6 mg) release after 3 hrs; 40 – 65 % ( 8- 13 mg) after 6 hrs. Based on this condition, only brands B and C fulfilled the USP requirement for drug dissolution.Keywords: In vitro, quality control, nifedipine, sustained release, tablet

Comparative studies on biological activity of generic and branded enoxaparin in vivo and vitro.

As per US Food and Drug Administration (FDA) requirement, the study was designed to conduct the fourth and fifth criteria of Abbreviated New Drug Application to demonstrate equivalence of generic and branded Enoxaparin in vivo and vitro.Pharmacodynamic behavior of branded and generic Enoxaparin was compared in a parallel study in rats based upon measurement of anti-FXa and anti-FIIa profiles. Blood samples collected at baseline and at 0.5, 1, 2, 4, 6, 8, 12 and 24 h postsubcutaneous administration of six batches of Lovenox and nine batches of generic Enoxaparin were evaluated for anti-FXa and anti-FIIa using chromogenic substrate method. Anti-FXa, Anti-FIIa, activated partial thromboplastin time (APTT), and Heptest prolongation time were conducted in vitro as per the United States Pharmacopeia method. Pharmacodynamics parameters were obtained including peak effect (anti-FXamax, anti-FIIamax), area under the effect curve (AUEC0-T and AUEC0-∞), Tmax, and T1/2.Pharmacokinetic differences were not observed using anti-FXa or anti-FIIa. No statistically significant differences were observed between branded and generic Enoxaparin either in vitro anti-FXa, anti-FIIa, APTT, or Heptest assay.It can be concluded that they are bioequivalent in anticoagulant activity tested in vivo and vitro.

COMPARATIVE STUDY OF DIFFERENT BRANDS OF RANITIDINE TABLETS IN BANGLADESH

Ranitidine is a H2- receptor blocker, which is widely used for the treatment of peptic ulcer disease. Present was designed to assess the therapeutic properties of different branded ranitidine hydrochloride tablets available in retail pharmacies of Bangladesh. Ranitidine HCl tablets manufactured by five different brands following USP specifications were collected from local retail Pharmacy located in Dhaka. Various parameters such as weight variation, thickness, hardness, disintegration, dissolution, potency etc. were analyzed according to the official (BP/USP8) pharmacopoeia methods to evaluate their quality. The result showed that four brands of Ranitidine HCl tablets complied USP specification of potency and the remaining one was more potent. Four brands showed a good result for weight variation, hardness, disintegration time and dissolution rate. One brand of tablets showed minor deviation in dissolution rate as compared to USP specification. It is evident from the study that most of the brands tested showed good results. Though this study was performed on a limited scale but the data reported here can help the Drug Control Authority to get an idea a