The small and simple benzothiazole nucleus is present in compounds involved in research aimed at evaluating new products that possess interesting biological activities, such as antitumor, antimicrobial, anthelmintic, antileishmanial, anticonvulsant and antiinflammatory. The present review focuses on the benzothiazoles with potential activities that are now in development.

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A simple, selective, rapid, precise and economical reverse phase HPLC method has been developed for the simultaneous estimation of paracetamol and aceclofenac from pharmaceutical dosage forms. The method was carried out on a Hichrom C18 (25 cm×4.6 mm i.d., 5 µ) column with a mobile phase consisting of acetonitrile:20 mM phosphate buffer (pH 5.0) (60:40 v/v) at a flow rate of 0.8 ml/min. Detection was carried out at 265 nm. Etoricoxib was used as an internal standard. The retention time of paracetamol, aceclofenac and etoricoxib was 4.75, 6.44 and 8.83 min, respectively. The developed method was validated in terms of accuracy, precision, linearity, limit of detection, limit of quantitation and solution stability. The proposed method can be used for the estimation of these drugs in combined dosage forms.

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The aim of this study was to prepare, using taste masked granules, rapidly disintegrating tablets of chlorpheniramine maleate, a bitter drug. The taste masked granules were prepared using aminoalkyl methacrylate copolymers (Eudragit E-100) by the extrusion method. In vitro release profile obtained at pH 6.8 indicate that perceivable amount of drug will not be released in saliva while high percent release (more than 80% in 30 min) would be obtained at acidic pH 1.2 of the stomach. These taste masked granules were directly compressed into tablets using sodium starch glycolate as a super-disintegrant. The prepared tablets containing the taste masked granules having sufficient strength of 3.5 kg/cm were evaluated for taste by both spectrophotometric method and through panel testing. Panel testing data collected from 20 healthy volunteers indicate successful formulation of oral fast disintegrating tablets which had good taste and disintegrated in the oral cavity within 30s.

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A new reversed-phase high performance liquid chromatography method was developed and validated for the simultaneous determination of losartan potassium and atenolol in tablets. The separation was achieved on Supelcosil ODS analytical column (25×0.46 cm, i.d., 5 µm) using acetonitrile and 25 mM potassium dihydrogen phosphate (45:55 v/v, pH 3.00±0.05) as mobile phase at a flow rate of 1.2 ml/min. Detection was carried out using a UV detector at 227 nm. The method was validated. The developed and validated method was successfully applied for the quantitative analysis of Losar beta® tablets. The total chromatographic analysis time per sample was about 6 min with atenolol, chlorzoxazone (internal standard) and losartan eluting at retention times of about 2.72, 4.89 and 5.61 min, respectively. The standard curves were linear over the concentration ranges, 1 to 10 µg/ml for losartan potassium and atenolol. The values obtained of LODs were 0.029 and 0.062 µg/ml and LOQs were 0.078 and 0.187 µg/ml for losartan potassium and atenolol, respectively. The proposed method is fast, accurate and precise for the determination of losartan potassium and atenolol for routine quality control of tablets containing these two drugs.

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The effects of methanol extract of Phyllanthus amarus on different phases of inflammation were examined. Investigations were performed using different phlogistic agents-induced paw edema, carrageenan-induced air-pouch inflammation and cotton pellet granuloma in rats. Methanol extract of Phyllanthus amarus significantly inhibited carrageenan, bradykinin, serotonin and prostaglandin E1-induced paw edema, but failed to inhibit the histamine-induced paw edema. Maximum inhibition was observed in prostaglandin E1-induced paw edema. In carrageenan air-pouch model, methanol extract of Phyllanthus amarus significantly reduced the volume of exudate and migration of neutrophils and monocytes. The extract significantly decreased formation of granuloma tissue in chronic inflammation model. The present study revealed that methanol extract of Phyllanthus amarus inhibits all the phases of inflammation.

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A floating drug delivery system of piroxicam in the form of microspheres was prepared using an enteric polymer and emulsification solvent-evaporation method. The microspheres remained buoyant continuously over the surface of acidic media containing surfactant for a period of 8-12 h in vitro . Differential scanning calorimetry and X-ray diffraction studies showed that drug incorporated in the outer shell of the polymer was completely amorphous. Scanning electron micrographs indicated that the microsphere is perfect sphere with an internal hollow cavity enclosed by a rigid shell of polymer. The micromeritic properties of microspheres were found to be much improved compared with original drug crystals. The in vitro drug release behavior of the floating microspheres was characterized as an enteric property. Polymer being soluble above pH 7.0, the drug release rates from microspheres changed dramatically above and below pH 7.0. At intestinal pH the drug release was faster and continuous as compared to the amount released at gastric pH.

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The 2-arylsubstituted benzothiazole derivatives were synthesized by refluxing o-aminothiophenol with substituted benzoic acids in the presence of polyphosphoric acid at 220°. 2-Mercaptothiazole was used along with thionyl chloride to get the carbothioates. The physical and spectral data such as mp, Rf, IR, NMR was obtained for the synthesized compounds and the structures were confirmed. The screening for antitumour activity was done as per the National Cancer Institute drug screening strategy 3 compounds were found to be significantly cytotoxic as compared to [2-(3-bromo-4-aminophenyl) benzothiazole] against the human cervical cancer cell lines.

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Different types of in situ gelling systems of indomethacin, in sodium alginate vehicle, were prepared and evaluated for their pharmaceutical properties including viscosity, sterility and drug content uniformity. The gelling efficacy of the prepared systems was evaluated by using an in house fabricated gelation cell. The in vitro release kinetics of the prepared systems was determined in simulated tear. The gelling time and the nature of the gel formed were dependent on the concentration of sodium alginate present in the systems. The drug release from these systems was extended up to 8 h and predominately followed zero-order kinetics.

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Major challenge for tablet manufacture comes from the powder characteristics of the materials to be compressed. This in turn poses a challenge in achieving greater productivity and better quality product especially on the new generation high-speed machines. Advancement in directly compressible materials has come in the form of co-processed spray dried materials. The present work evaluates and characterizes two spray dried co-processed materials, one comprising of microcrystalline cellulose, colloidal silicon dioxide and cross povidone and the other composed of microcrystalline cellulose, colloidal silicon dioxide and sodium starch glycollate. Prototype tablet formulations were developed with these co-processed materials using actives such as diclofenac sodium, iron polymaltose complex and amoxycillin trihydrate. Their performance was compared vis-à-vis conventionally processed tablet formulations as well as with leading marketed brands. This study revealed that the co-processed materials have excellent flow properties, high compressibility, render low disintegration time to tablets and have better binding properties. These materials can be a good substitute for inert granules, which are normally used in tablet manufacturing.

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The objective of the present work was to develop stomach specific delivery systems for amoxicillin and metronidazole using chitosan and poly(acrylic acid) hydrogels. Chitosan and poly(acrylic acid) hydrogels were prepared with different composition of copolymers. The hydrogels were evaluated for swelling studies, mucoadhesive studies, in vitro drug release, scanning electron microscopic and FTIR analysis. The effect of chitosan and poly (acrylic acid) on swelling and in vitro drug release was carried out. The n value calculated was <0.5 for all the formulations containing amoxicillin and metronidazole indicating Fickian diffusion mechanism. The hydrogels with chitosan and poly (acrylic acid) ratio of 0.25:1 showed greater mucoadhesive property, maximum swelling and complete release of drugs, hence can be used for stomach specific delivery of drugs.

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A pH-sensitive tablet in capsule system intended to approximate the chronobiology of nocturnal asthma is proposed for site specific release to the colon. The system comprising of Eudragit S-100 coated minitablets was designed for chronotherapeutic delivery of theophylline in view to specifically target the nocturnal peak symptoms of asthma. The drug-loaded core minitablets were produced by wet granulation procedure using alcoholic solution of PVP K 30 as a binder. Different coat weights of Eudragit S-100 were applied to the drug loaded core minitablets in a conventional coating pan to produce the pH sensitive minitablets. SEM revealed a distinct continuous acrylic coat free from cracks or pores. In vitro dissolution studies performed following pH progression method demonstrated that the drug release from the coated minitablets depended on the coat weights applied and pH of the dissolution media. The studies showed that a coat weight of 10% weight gain was sufficient to impart an excellent gastro resistant property to the tablets for effective release of the drug at higher pH values.

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A modified Pulsincap dosage form of metronidazole was developed to target drug release in the colon. Bodies of hard gelatin capsules were treated with formaldehyde keeping the caps as such. Metronidazole pellets prepared by extrusion-spheronization method were incorporated into these specialized capsule shells and plugged with polymers guar gum, hydroxypropylmethylcellulose 10K, carboxymethylcellulose sodium and sodium alginate separately at concentrations 20 mg, 30 mg and 40 mg. The filled capsules were completely coated with 5% cellulose acetate phthalate to prevent variable gastric emptying. All the formulations were assayed to determine drug content and the ability of the modified Pulsincap to provide colon-specific drug delivery was assessed by in vitro drug release studies in buffer pH 1.2 for 2 h, pH 7.4 (simulated intestinal fluid) for 3 h and pH 6.8 (stimulated colonic fluid) for 7 h. The results indicated that significant drug release occurred only after 5 h from the start of experiment. Thus, metronidazole could be successfully colon targeted by the use of the modified Pulsincap, thereby reducing systemic side effects.

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Antiaging therapy, a recent medical discipline, aims high quality of health for people in second half of their lives. Advocates of antiaging therapy claim that it is now possible to slow or reverse aging through medical and scientific interventions. Preventive measures make up an important part of antiaging program. Careful adherence to nutrition, hormonal and cell based therapies, genetic manipulations, other medications and supplements can increase one's chances of living a healthy life.

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Seed oils of Gynandropsis gynandra, Impatiens balsamina, Celastrus paniculata, Embelia ribes and Mucuna pruriens were investigated for their anthelmintic property against Pheritima posthuma . Three concentrations (10, 50 and 100 mg/ml) of each oil were studied in a bioassay, which involved the determination of time of paralysis and time of death of the worm. All the oils exhibited moderate to significant anthelmintic activity. Embelia ribes showed the best anthelmintic activity in both the parameters. Piperazine citrate (10 mg/ml) was included in the assay as standard reference drug.

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A simple, rapid, precise and accurate gas liquid chromatographic method was developed for the determination of ethanol in marketed preparation of abhayarishta using flame ionization detector. The separation was performed employing carbowax 20 M stainless steel column using nitrogen as a carrier gas at optimized conditions. The column was maintained at 90°, while injection port and detector were maintained at 110°. The system suitability parameters were studied throughout the study. The method has been applied successfully for the assay of ethanol in abhayarishta . The recovery values were found to be in the range of 98.14-104.54% with RSD values less then 0.800%. The proposed method can be used for the determination of generated ethanol content in abhayarishta preparation.

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Simple and reproducible HPTLC method was developed for the separation and quantitation of simvastatin, pravastatin sodium and rosuvastatin calcium, cholesterol lowering agents in pharmaceutical dosage forms. The stationary phase used was precoated silica gel 60F ₂₅₄ . The mobile phase used was a mixture of chloroform:methanol:toluene (6:2:2, v/v/v). The method has been completely validated and proved to be rugged. Calibration curves were linear over the studied ranges with correlation coefficients grater than 0.999. All the drugs were extracted from the respective tablets using methanol. The percentage recoveries ranged from 100 to 101 for simvastatin, 98 to 101 for pravastatin sodium and 98 to 102 for rosuvastatin calcium. The LOD for simvastatin, pravastatin sodium and rosuvastatin calcium were found to be 15, 9 and 8 ng/spot, respectively and LOQ were 200 ng/spot for simvastatin and 100 ng/spot for pravastatin sodium and rosuvastatin calcium. The method can be useful in the quality control of bulk manufacturing and tablet dosage forms.

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Quantitative analysis of poorly water-soluble drugs involves use of various organic solvents. Major drawbacks of organic solvents include high cost, volatility and toxicity. Safety of analyzer is affected by toxicity of the solvent used. Sodium benzoate is one of the widely used hydrotropic agents and has demonstrated the enhancement in aqueous solubilities of a large number of poorly water-soluble drugs. In the present investigation 2 M sodium benzoate solution has been used as hydrotropic solubilizing agent for three poorly water-soluble, non-steroidal antiinflammatory drugs ibuprofen, flurbiprofen and naproxen. There were more than 80, 110 and 120 fold enhancements in the solubilities of ibuprofen, flurbiprofen and naproxen, respectively in 2 M sodium benzoate solution as compared to solubilities in distilled water. Therefore, 2 M sodium benzoate solution was employed to solubilize these drugs to carryout their titrimetric analyses. These drugs have been analyzed successfully in basic drug samples and in solid dosage forms. Proposed method is new, simple, economic, safe, rapid, accurate and reproducible. The results of analysis obtained by the proposed methods compared well with those obtained by corresponding pharmacopoeial methods. Recovery studies and statistical data proved the accuracy, reproducibility and the precision of the proposed methods. Presence of sodium benzoate did not interfere in analysis.

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The present study aims to present a representative view of the existing situation of availability and price variation, by comparing data about brand availability, and difference in pricing between various brands of 20 drugs under six therapeutic categories. The project involved collecting data from 10 retail outlets from the city area, 10 outlets from town area and 15 retail outlets from the rural area spread over a time span of 6 months. The drug categories studied were analgesics, antibiotics, drugs acting on cardiovascular and central nervous system, drugs acting on gastrointestinal tract and steroids. Data analysis showed that as compared to data on national availability of different brands, the number of brands available in the town, city and rural segments in general, are less. In all sectors, town, city and rural areas, almost equal number of brands is found to be available, with a slightly higher availability in the cities. Price difference between different brands (single drug or drug combinations) varies up to an extent of 881% (in case of amlodipine) on the higher side, and the lowest being 7% (in case of doxycycline). Out of all brands studied, it was observed that the highest priced brand was the most sold brand in cases of 5 products (single drug/combinations), and the lowest priced brand was the most sold in case of 2 products. It emerged that prices of drug molecules including those under National Essential Drug List, increased during 1996-2004 to a certain extent. It was noted, that % increment of price of drugs under Drug Price Control Order was less than those of drugs not under the purview of Drug Price Control Order. The difference in price between various brands of the same drug is too wide.

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A simple, fast, precise and accurate liquid chromatographic method was developed for the simultaneous estimation of paracetamol and domperidone in combined dosage forms. This combination is used for antiemetic and pain associated with gastrointestinal disorders. Drugs are chromatographed on a reverse phase Kromasil C18 column using a mobile phase, 20 mM phosphate buffer (pH 7.0±0.1) and acetonitrile in the ratio of 60:40%v/v. Diclofenac potassium was used as an internal standard. The retention time of paracetamol, domperidone, and diclofenac potassium was 2.94, 8.30, 5.67 min, respectively. The validation of the proposed method was also carried out. The method was found to be linear (r>0.99), precise (%RSD: 0.49% for paracetamol and 0.89% for domperidone), accurate (overall average recovery yields: paracetamol 99.1% and domperidone 98.36%) and selective. Due to its simplicity and accuracy the proposed method can be used for routine quality control analysis of these drugs in combined dosage form.

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Two simple, accurate, fast and economical methods have been developed for the quantitative estimation of aceclofenac and indapamide from their respective tablet formulation using Folin-Ciocalteu reagent. Aceclofenac forms a blue colored chromogen with the reagent, which shows absorbance maxima at 642.6 nm and linearity in the concentration range of 80-160 µg/ml of drug. Indapamide forms a green colored chromogen with the reagent, which shows absorbance maxima at 783.2 nm and linearity in the concentration range of 2-12 µg/ml of drug. The results of analysis for both the methods were validated statistically and by recovery studies.

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A reverse phase high performance liquid chromatographic method to determine aspirin and clopidogrel in combined dosage form is proposed. The chromatographic resolution of aspirin and clopidogrel was obtained in a mobile phase consisting of 0.1% v/v triethylamine (pH 4.0):acetonitrile in the ratio 25:75% (v/v) in an isocratic elution. A detection wavelength of 225 nm and flow rate of 1 ml/min was used in the study. Nimesulide (20 µg/ml) was used as an internal standard. The system suitability procedures as precision, accuracy, LOD, LOQ, number of theoretical plates and tailing factor were studied.

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A rapid, simple, accurate and precise UV Spectrophotometric method using simultaneous equation was developed for the simultaneous determination of amlodipine besylate and atorvastatin calcium in a binary mixture. In the proposed method, the signals were measured at 238.2 and 246.6 nm corresponding to the absorbance maxima of amlodipine besylate and atorvastatin calcium in methanol, respectively. Linearity was observed in the concentration range of 5-30 µg/ml for both the drugs. Concentration of each drug was obtained by using the absorptivity values calculated for both the drugs at two wavelengths, 238.2 and 246.6 nm and solving the simultaneous equations. The method was validated statistically and recovery study was performed to confirm the accuracy of the method. Laboratory prepared synthetic mixture was successfully analyzed using the developed method.

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In the present study, interpenetrating polymeric network hydrogels of glipizide were prepared using gelatin and methacrylic acid. Methacrylic acid was polymerized using potassium persulfate. Methacrylic acid was crosslinked with methylene bisacrylamide and gelatin was crosslinked using glutaraldehyde. Four formulations were prepared by varying the concentrations of methacrylic acid, methylene bisacrylamide and glutaraldehyde. The amounts of gelatin and potassium persulfate were kept constant in all the formulations. The interpenetrating polymeric network hydrogels were characterized by fourier transform infrared analysis, differential scanning calorimetry and evaluated for swelling and deswelling properties, drug loading and in vitro drug release. All the formulations showed no interaction between drug and polymer as confirmed by fourier transform infrared analysis and differential scanning calorimetric studies. The interpenetrating polymeric network hydrogels swelled only in alkaline pH and swelling was minimal in acidic pH. It was found that as the concentration of cross-linking agents is increased, there is a decrease in swelling and, as the concentration of methacrylic acid is increased, there is an increase in swelling. The release data shows that, as the concentration of methacrylic acid was increased, swelling increased resulting in increased release of the drug.

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In the present investigation mefenamic acid prodrug of β-cyclodextrins was synthesized. The primary hydroxy group of β-cyclodextrins was used to block the acid group. The synthesis involved a series of protection and deprotection reaction. The ester was evaluated for stability in simulated gastric and intestinal fluid. The hydrolysis of cyclodextrin conjugate in colon is confirmed by the hydrolysis kinetics studies in rat faecal material. The ester was also evaluated for ulcerogenicity. Results of these studies established the primary aim of masking the ulcerogenic potential of free drug, by using 12-fold dose of the normal dose of mefenamic acid and equivalent doses of the ester.

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Pharmacogenomics deals with the interactions of individual genetic constitution with drug therapy. It is very likely that pharmacogenetic tests will make up a significant proportion of total molecular biology testing in future. Therefore, this article emphasizes the applications of pharmacogenomics, and computational genome analysis in drug therapy.

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The present paper describes two simple, accurate, rapid, precise and economical procedures for simultaneous estimation of chlordiazepoxide and trifluoperazine hydrochloride in combined tablet dosage formulations. The first meth¬od is based on the multicomponent mode of analysis of the instrument used; the second method is developed on simultaneous equations. The Shimadzu 1700 pharmaspec UV/Vis spectrophotometer with a matched pair of 10 mm quartz cells was used for experimental purpose. Both the drugs obeyed Beer's law in the concentration range employed for the analysis. For all these methods 0.1 M HCl was used as a solvent. In this solvent system chlordiazepoxide showed maximum absorbance at a wavelength of 245 nm and trifluoperazine hydrochloride showed maximum absorbance at a wavelength of 255.5 nm. The results of analysis were validated statistically and by recovery studies.

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Present investigation describes statistically the influence of viscosity of hydroxypropyl methylcellulose and types of filler on dipyridamole release from floating matrix tablets using 3 ² full factorial design. Tablets were prepared using direct compression technique. Tablets were evaluated for in vitro floating ability and drug release study using USP 24 types II paddle apparatus using 0.1 N HCl (pH 1.2) at rotation of 100 rpm and temperature of 37±0.5°. Multiple regression analysis was performed for dependent variables studied and to evaluate contribution of factors with their levels two way ANOVA was performed followed by Tukey test. Polynomial equations and response surface plots were generated for all dependent variables. It was observed that both the factors had significant influence on all dependent variable studied (p<0.05). It was observed that as viscosity of polymer increases the release rate constant was decreased. Release rate obtained was highest when microcrystalline cellulose was employed as filler followed by dicalcium phosphate and lactose. Mechanism of drug release was anomalous types and depends upon viscosity of polymer and types of filler used. Microcrystalline cellulose gave release mechanism nearer to diffusion mechanism while dicalcium phosphate and lactose gave anomalous release. It was observed that both the factors had significant contribution on all dependent variables studied. A major controlling factor for kinetics of drug release was viscosity of polymer and it can be modified by incorporation of different types of filler. In initial phase of drug release viscosity of polymer and types of filler both governs the drug release while in later phase only the viscosity of polymer predominates.

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Arylamines on diazotization and further treatment with dicyandiamide yielded aryldicyandiamide (1a-d), which on addition with aminoxy compound (2) gave corresponding biguanides (3a-d). Cycloaddition of biguanide with ethylchloroacetate furnished 2,4,6-trisubstituted-s-triazines (4a-d). Subsequent treatment of these compounds with N-hydroxyphthalimide or N-hydroxysuccinimide in presence of triethylamine gave final compounds (5a-h). IR, ¹ H NMR and mass spectra were used to confirm their structure. Compounds (5a-h) were screened for antibacterial ( Escherichia coli, Proteus vulgaris, Klebsiella pneumoniae, Pseudomonas aureus and Staphylococcus aureus ) and antifungal ( Candida albicans and Aspergillus fumigatus ) activities. Antibacterial activity revealed that compounds 5a, 5b, 5c, 5g showed comparable activity against bacteria P. vulgaris, P. aureus, where rest of the compounds showed weak activity against all the pathogenic bacteria. The fungicidal data indicated that compound 5d possess high level activity and rest of the compounds showed comparable to the standard.

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Xanthine oxidase activity containing fractions from rat, mouse, rabbit and guinea pig livers were obtained by heat treatment and ammonium sulfate precipitation. Xanthine oxidase activity was observed in rat and mouse liver fractions, while xanthine oxidase activity was absent in rabbit and guinea pig liver fractions. Enzyme kinetic parameters, K_m and V_max, were determined for the conversion of xanthine to uric acid by rat and mouse live fractions, by both spectrophotometric and HPLC methods. The Km values obtained by either method for both animal liver fractions were in the range of 5.32-13.8 µM.

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Two simple and sensitive visible spectrophotometric methods (A and B) have been developed for the quantitative estimation of nitazoxanide, in bulk drug and pharmaceutical dosage forms. Methods were based on the formation of reddish yellow coloured and green coloured chromogens, which were measured at 544 nm and 715 nm, respectively. The results obtained with the proposed methods are in good agreement with the labelled amounts when tablet dosage forms were analysed.

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A simple, precise, fast and selective HPLC method has been developed for the simultaneous estimation of lamivudine, zidovudine and nevirapine from tablets by external standard method. The analytes were resolved by using mobile phase of 50:50 mixture of methanol:buffer (0.1 M ammonium acetate in 0.5% glacial acetic acid) on an Inertsil ODS 3V (250 × 4.6 mm, 5 µ) column as a stationary phase and UV 270 nm as detection wavelength.

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A simple, precise, accurate and rapid high performance thin layer chromatographic method has been developed and validated for the determination of cefuroxime axetil in dosage form. The stationary phase used was precoated silica gel 60F ₂₅₄ . The mobile phase used was a mixture of chloroform:methanol:toluene (4:2:2 v/v). The detection of spot was carried out at 290 nm. The method was validated in terms of linearity, accuracy, precision and specificity. The calibration curve was found to be linear between 300 to 800 ng/spot for cefuroxime axetil. The limit of detection and the limit of quantification for the cefuroxime axetil were found to be 50 ng/spot and 100 ng/spot. The proposed method can be successfully used to determine the drug content of marketed formulation.

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Semi-interpenetrating polymer networks of poly(vinyl alcohol) and poly(methacrylic acid) were prepared by free radical polymerization of methacrylic acid in presence of poly(vinyl alcohol) using N,N-methylenebisacrylamide as cross linking agent. The dynamic swelling behavior of the semi-interpenetrating polymer networks was studied to determine the water transport mechanism. The effect of cross linking agent and methacrylic acid concentration on the swelling and insulin release characteristics were evaluated. Swelling ratio and water diffusion coefficients were used to characterize the water uptake process. Swelling rates correlated well with the polymer composition, the slowest rate of water uptake was observed in hydrogel samples containing large quantities of N,N-methylenebisacrylamide and maximum swelling was observed with hydrogels containing higher methacrylic acid content. The mechanism of water transport in these semi-interpenetrating polymer network hydrogels was significantly affected by the pH of the swelling medium. At pH 2.0 mechanism was Fickian (diffusion controlled) and became case II (relaxation controlled) at pH 7.4. Insulin was incorporated by active loading technique and the insulin incorporated in the semi-interpenetrating polymer network hydrogels was in the range of 28-35%. The formulations showed decreased insulin release in pH 2.0, while complete release was observed in pH 7.4 pH buffer. The diffusion coefficient of insulin through the hydrogels was in the range of 3.84×10 ^-6 to 5.59×10 ^-6 cm ² /min in pH 2.0 buffer and in pH 7.4 buffer it was in the range of 7.55×10 ^-6 to 21.636×10 ^-6 cm ² /min.

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A new simple, sensitive and precise high performance thin layer chromatographic method has been developed for estimation of paracetamol and valdecoxib simultaneously from a combined dosage form. In this method pre coated silica gel 60 GF ₂₅₄ TLC plate was used as stationary phase and the chromatogram was developed using chloroform: isopropyl alcohol: glacial acetic acid (9.5:1:0.2 v/v/v) as mobile phase. Paracetamol and valdecoxib showed Rf values 0.14±0.01 and 0.51±0.03, respectively. The plate was scanned and quantified at 250 nm using Camag TLC Scanner. The linear concentration was 2.5 to 12.5 µg/spot for paracetamol and 0.1 to 0.5 µg/spot for valdecoxib. The %RSD of intra day variation was 0.18±0.01 for paracetamol and 0.24±0.01 for valdecoxib. For inter day variation the %RSD was 0.03±0.005 and 0.1±0.02 for paracetamol and valdecoxib, respectively.

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Broad range of structurally diverse alkylphenols has been found to be considerably potential estrogenic agents in combating estrogen-linked pathologies, but their mechanism of action in mimicking responses of endogenous hormones is still to be understood. The present work explores pharmacophore signals of some varied alkylphenols and predicts estrogenic activities through generated linear relations implementing theoretical molecular modeling techniques. The binding affinity to estrogen receptor of alkylphenols has been modeled investigating large data set of whole molecular and atomic descriptors. Univariate and multivariate relationships were estimated using correlation analysis and statistical significance of the generated relations assessed. The predictive ability of the generated models was further verified using 'Leave-One-Out' cross validation. The relationships with molecular properties could be developed with a maximum correlation exceeding 94%, with explained variance as high as 87% and cross-validated variances >0.8. It was inferred that increased molecular bulk, enhanced molecular ionization potential, presence of electron donating groups in para position and branched chain terminal atoms might have influence on binding affinity to the receptor.

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The ring opening of phthalimide derivatives viz N-cyclopentylphthalimide (1a), N-benzylphthalimide (1b), N-prop-2-ynylphthalimide (1c), 1-phthloylamino-3-[4-(2-methoxyphenyl)-piperizin-1-yl]-propane(1d) and 1-phthloylamino-4-[4-(2-methoxyphenyl)-piperizin-1-yl]-butane (1e) was accomplished using benzylamine in dimethylformamide (DMF) at room temperature to afford the corresponding carboxamides: benzamido-cyclopentane-2-(N-benzyl)-carboxamide (3a) benzamido-1-phenylmethylene-2-(N-benzyl)-carboxamide (3b) and 3-benzamido-prop-2-yne-2-(N-benzyl)- carboxamide (3c) and were unequivocally characterized by infrared, nuclear magnetic resonance, mass spectrometer and elemental analyses. The products obtained were screened for antiinflammatory and analgesic properties using carrageenan-induced rat paw oedema assay and acetic acid-induced writhing test, respectively. The most active compound was 3b for the antiinflammatory activity assay and for the analgesic activity test the most active compound was 3a. The activities were dose-dependent. All the compounds tested showed better analgesic activity than acetylsalicylic acid.

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Antimitotic activity of new synthetic analogues benzyl (4), cyclohexyl (5) and 1,4-ethylenedioxy cyclohexyl (6) of β-apopicropodophyllin has been determined by onion root tip method. Analogues 4,5 and 6 synthesised in the present work showed strong to moderate antimitotic activity. They might bind to the critical cells either through hydrophobic forces or acylation is not clearly known but inhibits mitosis in the critical cells.

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Effects of high doses of vitamin A on the biochemical parameters of the adrenal gland of 10 d to 40 d old Swiss albino mice were studied by measuring total protein and cholesterol content, acid phosphatase and alkaline phosphatase enzyme levels. The animals were divided into four different age groups for both control and test groups. Control groups did not show any significant change in total protein amount, cholesterol content, acid phosphatase and alkaline phosphatase during the entire period of study. Total protein and cholesterol content of test groups decreased significantly at higher dose levels of vitamin A. Acid phosphatase and alkaline phosphatase contents were elevated at each dose level. The result of this study revealed that vitamin A is responsible for stimulation of adrenal gland activity through increased corticoid synthesis and membrane permeability.

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Starting chloropropane derivative (2) was prepared by the reaction of 2-methyl-8-hydroxyquinoline (1) with 1- bromo-3-chloropropane in presence of a base. Various new 1-(2-methyl-8-quinolyloxy)-3-propylamines (3a-3j) have been synthesized by the condensation of 1-(2-methyl-8-quinolyloxy)-3-chloropropane (2) with different amines. Compounds were screened for the possible central nervous system depressant activities. Some of them showed moderate central nervous system depressant activity.

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Two simple, rapid, accurate and economical methods have been developed for the estimation of valdecoxib and tizanidine HCl in the mixture. Valdecoxib has an absorbance maximum at 243 nm and tizanidine HCl has two absorbance maxima at 228 nm and 320 nm in methanol:0.1 M HCl (1:1) mixture. The linearity was observed in the concentration range 5-30 µg/ml for valdecoxib and 2-20 µg/ml for tizanidine. First method is based on the simultaneous equations and second method is based on Q absorbance ratio. Absorbances at 243 nm and 228 nm were selected for simultaneous equations method. Absorbance at isoabsorptive point 280.4 nm and at 243 nm, the λ_max of valdecoxib were selected for absorbance ratio method. These methods were validated statistically. The recovery studies confirmed the accuracy of the proposed methods.

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Stability studies of some novel dual action fluoroquinolonyl-3'-penicillin amides (1a-e) in aqueous DMF (1:1) solution has been carried out in presence of Cu (ic) or Hg (ic) ions and their degradation rate was monitored by UV/Vis spectrophotometric method. The results thus obtained indicate that ciprofloxacin moiety offered greater stability to the β-lactam moiety of the hybrid (1d or 1e) than norfloxacin (1a or 1b) in the presence of heavy metal ion degradation; whereas the degradation pattern of β-lactam moiety in the hybrids under investigation (1a-e) was found to be in agreement with the previously reported heavy metal ion degradation profile of the penicillins.

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A simple analytical method for the estimation of tegaserod maleate has been developed to analyze the drug in bulk and in tablet formulation. The method is based on difference spectroscopy and is quite simple, rapid, inexpensive and sensitive. The Beer's law range was followed in the concentration range of 1-30 µg/ml of tegaserod maleate. The molar absorptivity was 1.7920×10 ⁴ l/mole/ cm. The method does not require any separation of soluble excipients as they do not interfere in the estimation.

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