Recent scientific and patent literature shows increased interest in academics and industrial research groups regarding the novel dosage forms that can be retained in the stomach for a prolonged and predictable period of time. One of the most feasible approaches for achieving a prolonged and predictable dug delivery profiles in the gastrointestinal tract is to control the gastric residence time, using gastroretentive dosage forms that will provide us with new and important therapeutic options. From the formulation and technological point of view, the floating drug delivery system is considerably easy and logical approach. An attempt has been made in this review article to introduce the readers to the current technological developments in floating drug delivery system.

Prominence of chirality of drugs has been increasingly recognized, and the consequence of using them as racemates or as enantiomers has been frequently discussed in pharmaceutical literature during recent years. This awareness on issues pertinent to chirality in drug design and drug development had increased chiral explorations. This in turn had augmented the need for good chiral analytical tools. Consequently, now a spectrum of enantiospecific analytical methodologies such as physical (includes optical rotation, circular dichroism, nuclear magnetic resonance spectroscopy, infrared spectroscopy, and powder X-ray diffraction), biological (viz. enantiospecific immunoassay and radioreceptor assay) and separation science methods(includes gas chromatography, supercritical fluid chromatography, high performance liquid chromatography and capillary electrophoresis) are available for chiral examination of drugs. In this context, the present article provides a gist of various options available for chiral analysis and examines in detail the direct chiral high performance liquid chromatographic technique, with reference to application in enantiospecific drug analysis.

Psoriasis is an inflammatory papulosquamous skin disease associated with rapid epidermal proliferation, essentially a disorder of the immune system. Genes and immune events play a key role in the pathogenesis of psoriasis. Levels of arachidonic acid and of its metabolites, polyamines, plasminogen activator, calcium binding protein calmodulin, certain interleukins (IL-1, IL-2, IL-6 and IL-8) and growth factors (TNF-α and TGF α) are elevated. Plaque pattern, guttate pattern, local pustular psoriasis, scalp, nails, flexures, palms, napkin psoriasis, erythrodermic psoriasis are the common presentations. Various therapeutic strategies are available for the treatment of this disease. The disadvantages associated with these treatments have made them unsuitable for use. Research is being carried out to study the effectiveness of review vitamin D3 analogue i.e. calcipotriol in the management of psoriasis. This analogue has potent immunological properties and it acts by directly regulating keratinocyte proliferation and differentiation.

Nimesulide, a non-steroidal antiinflammatory drug with very short biological half-life was encapsulated within lipid microspheres by a modified solvent evaporation method with an aim of targeting the drug to the site of inflammation and for controlled release. Physiological lipids such as glyceryl tristearate, cholesterol were used instead of synthetic polymer matrix materials. The prepared lipid microspheres were evaluated with respect to particle size distribution, encapsulation efficiency, in vitro release behaviour and in vivo antiinflammatory activity in rats. Lipid microspheres with a suitable average particle size of 6-7μm could be prepared with this method. The drug was released continuously over 12 days with no burst effect with a maximum release of 74%. The in vivo drug release was investigated in rats, by measuring antiinflammatory activity using cotton pellet granuloma method. A single administration of lipid microspheres showed a better antiinflammatory activity when compared to equivalent multiple administrations of the standard nimesulide solution. The drug concentration was higher in the tissues at the site of inflammation of lipid microspheres treated rats. These results indicated the possibility of drug being released at a controlled rate from lipid microspheres and targeted at the inflamed cells.

Fenofibrate is among the drugs of choice for treatment of hypertriglyceridemia and low levels of high-density lipoprotein. Its metabolite fenofibric acid is responsible for the pharmacodynamic effects of the drug. Two fenofibrate formulations were investigated in 18 healthy, Indian, male volunteers to demonstrate bioequivalence between these formulations. A single dose of 160 mg was given to volunteers in a two way randomized fashion with a wash out period of fourteen days. Blood samples were collected till 96 h following drug administration. Fenofibric acid concentrations were determined using a validated HPLC method using UV detector at wavelength of 287 nm. Additionally in vitro tests were performed using both the formulations to see the dissolution characteristics. The mean peak plasma concentration for the fenofibric acid (Cmax) as 5.52 and 5.35 μg/ml for test and reference formulations. The Cmax was achieved at 3.39 (test formulation) and 3.00 (reference formulation) h. The area under the plasma-concentration-time-curve AUC0-t and AUC0-∞ had mean values of 135.1 and 156.4 μg.h/ml for the test formulation and 124.9 and 139.6 μg.h/ml for reference formulation. The resulting 90% confidence intervals of the parameter ratios were (85.0, 112.1) for Cmax, (8 9.1, 117.5) for AUC0-t and (90.3, 119.4) for AUC0-∞. Though the bioequivalence criteria were met, test formulation showed a little higher value of all the considered pharmacokinetic parameters. Interestingly, this difference correlated well with the observation of more dissolution from the test formulation.

A high performance liquid chromatographic method for the determination of ornidazole in human serum using tinidazole as internal standard is described. Protein precipitation is used for the preparation of sample. Mobile phase consisting of 0.002 M phosphate buffer (pH-4.8), methanol and acetonitrile mixture (70:10:20 v/v/v) was used at the flow rate of 1ml/min on a C18 column. The eluate was monitored using an UV/Vis detector set at 318 nm. Ratio of peak area of analyte to internal standard was used for quantification of serum samples. The absolute recovery was greater than 90% over a concentration range of 1 to 20 0 μg/ml and the limit of quantitation was 0.05 μg/ml. The inter- day relative standard deviation ranged from 1.02 to 3.70 at 1 μg/ml, 0.96 to 3.62 at 2 μg/ml, 3.33 to 5.01 at 10 μg/ml and 1.16 to 5.03 at 20 μg/ml and for intra-day, 1.03, 2.16, 1.95 and 1.23 at 1, 2, 10, 20 μg/ml, respectively. The method was found to be simple, sensitive and could be used in the pharmacokinetic study involving human volunteers.

Reactions carried out under microwave irradiation are found to be faster and the technique is being used in laboratories for a variety of purposes. In order to introduce microwave technique for pharmaceutical chemistry practical, its use in quantitative and qualitative analysis and loss on drying is discussed. Quantitative estimation of amide, ester, and carbonyl compounds was successfully carried out. The percent purity obtained for all the samples was higher than those obtained through conventional methods and the time consumed was also found to be less by the microwave technique. Preparation of nitrate, oxime and hydrazone derivatives of organic molecules was successfully completed in a short duration. Determination of loss on drying was also achieved in a shorter duration. The procedures developed can be used for routine analysis in Pharmaceutical Chemistry laboratories.

Timolol maleate ocuserts were prepared using different polymers such as hydroxypropylmethylcellulose, ethyl cellulose, Eudragit RL100 and Eudragit RS100 at various concentrations. The in vitro release of the drug from the formulations was studied using commercial semi permeable membrane. The physicochemical parameters of ocuserts were evaluated. A zero order release formulation I (drug reservoir with 1.25% hydroxypropylmethylcellulose and 1.25% ethyl cellulose and 2% hydroxypropylmethylcellulose as rate controlling membrane) was subjected to in vivo studies. The expected zero order release for one day was observed in formulation I (drug reservoir with 1.25% hydroxypropylmethylcellulose and 1.25% ethyl cellulose and 2% hydroxypropylmethylcellulose as rate controlling membrane).

The anionic surfactant sodium lauryl sulphate was incorporated in different concentrations (I%, 2% and 3%) to solid dispersions of nalidixic acid prepared using PEG-6000 as a carrier by meltsolvent method. The prepared dispersions were characterized by release studies, X-ray diffraction, infrared spectroscopy and thin layer chromatographic analysis. The effect of aging on the release of nalidixic acid was also studied. An almost instant and complete dissolution was obtained for dispersions with 1% w/w sodium lauryl sulphate than pure drug and dispersions without surfactant. The mechanism for increase in the release rate was also investigated. The results were supported by X-ray diffraction studies, which indicated a significant decrease in crystallinity of drug in all the prepared batches. These suggestions were also supported significantly by Infrared spectroscopy and thin layer chromatographic analysis of the samples. The samples were also found to possess adequate stability.

Mucoadhesive patches for delivery of diclofenac sodium were prepared using polyvinyl alcohol, hydroxyethyl cellulose and chitosan. Swelling and bioadhesive characteristics were determined for both plain and medicated patches. The results showed an increase in radial swelling after addition of diclofenac sodium to the plain formulation. A decrease in residual time observed for polyvinyl alcohol and chitosan containing formulae. High drug release was obtained from polyvinyl alcohol compared to the hydroxyethyl cellulose. Physical characteristics of the studied patches showed promising with good bioadhesion.

The low bioavailability and ocular residence time exhibited by the topical conventional liquid ophthalmic formulations because of spillage by overflow, dilution of drug by tear turn over, nasolacrimal drainage and systemic absorption may be overcome by the use of in situ forming systems that are instilled as liquid drops into the cul-de-sac of the eye, where they transform into a gel or semisolid phase. The present work describes the formulation and evaluation of an ophthalmic delivery system of an antiinflammatory drug, indomethacin for the treatment of uveitis based on the concept o f pH induced in situ gelation. The carbopol solutions which are acidic and less viscous, transform into stiff gels upon increase in pH of eye as the gelling agents and its combination with hydroxypropylmethylcellulose-K15 M, a well known ocular viscosity enhancing agent. The enhanced therapeutic efficacy and sustained release of indomethacin over 8 hour period in vitro make them an excellent candidate for in situ gelling ocular delivery systems.

In the present investigation, the enhancement of dissolution rate of roxithromycin was carried out by preparing solid dispersions using hydrophilic polymers like polyethylene glycol 6000, hydroxypropylmethylcellulose K4M and hydroxypropylcellulose, each in the ratios of 1:1, 1:3 and 1:5. Physical mixing and coprecipitate techniques were employed to prepare formulations for increasing the solubility of roxithromycin. Formulations prepared by both physical mixing and coprecipitate methods have shown significant enhancement of dissolution rates compared to pure roxithromycin alone. All the solid dispersions obtained were fine and having good flow properties. The formulation, polyethylene glycol 6000:CP5 containing roxithromycin:polyethylene glycol 6000 in 1:5 ratio has shown 99.4% drug release in 1h. The dissolution rate of roxithromycin was directly proportional to the increment in the drug to polymer ratios in the solid dispersions. Dispersions prepared by coprecipitate method have shown faster dissolution rate compared to physical mixing techniques. The dissolution efficiency of the formulation polyethylene glycol 6000:CP5 was found to be highest compared to other formulations. The release profiles of roxithromycin from the dispersions have followed first order release kinetics and Hixson-Crowell's cube root law. It was concluded that hydrophilic polymers can be employed to prepare solid dispersions to enhance the solubility of roxithromycin.

Amoxycillin trihydrate, a broad spectrum antibiotic, is a poorly water-soluble drug and has low bioavailability on oral administration. Solubility parameter of the drug (δ2) was evaluated in blends of ethyl acetate-propylene glycol and water-propylene glycol in the ratios 100:0, 75:25, 50:50, 25:75 and 0:100. The results obtained were compared with the δ2, values obtained using Molar Volume method and Fedor's group substitution method. Ethyl acetate-propylene glycol (75:25) was found to give maximum solubility with an experimental value of 13.32 H in comparison to the theoretical values of 13.25 H by molar volume method and 15.46 H from Fedor's group substitution method. In vitro drug release studies and antibacterial effect were evaluated with an intention to study the effect of the solvent blends on the drug release and its activity. In the in vitro studies, the water-propylene glycol (100:0) and the ethyl acetate-propylene glycol (50:50) ratios gave maximum release of the drug in their respective blends. The results of the in vitro studies correlated with the antibiotic Study conducted on both binary blends.

The present work comprises the formulation and evaluation of metoprolol tartarate transdermal drug delivery system for controlled release of drug for extended period of time. Eudragit RL and hydroxypropylmethylcellulose were used for fabrication of the matrix diffusion controlled transdermal drug delivery system. These transdermal drug delivery systems were characterized for their thickness, tensile strength and drug content. Then they were characterized for in vitro release kinetics and drug skin permeation studies. The system comprising of RL:hydroxypropylmethylcellulose in 40:60 ratio exhibited drug skin permeation 87.5 μg/h/cm2. This transdermal system was evaluated for its in vivo performance studies and compared its drug plasma profile with those obtained with oral multiple doses administered of conventional tablets of metoprolol tartarate. The transdermal drug delivery system exhibited better and constant drug plasma profile for 24 h as compared to oral administration.

A simple, specific, precise and rapid high performance thin layer chromatography method has been developed for estimation of phenytoin sodium, phenobarbitone sodium and carbamazepine simultaneous!y in tablet dosage form. In this method, standard solution and sample solution of phenytoin sodium, phenobarbitone sodium and carbamazepine were applied on precoated silica gel G60 F254 TLC plate and developed using a mixture of acetone:toluene (100:40 v/v) as mobile phase. The quantification was done by densitometry at 217 nm. This HPTLC system was quantitatively evaluated in terms of linearity, accuracy, precision, repeatability and specificity proving the utility in estimation of drug content in tablet dosage form.

Two simple, rapid, accurate and economical methods have been developed for the estimation of gatifloxacin and ornidazole in the mixture. Gatifloxacin has absorbance maxima at 286.2 nm and ornidazole has absorbance maxima at 319 nm in distilled water. The linearity was observed in the concentration range of 2-14 μg/ml for gatifloxacin and 2-20 μg/ml for ornidazole. First method is based on the simultaneous equations and second method is based on Q-absorbance ratio. Absorbances at isoabsorptive point 299.2nm and at the λ-max of ornidazole. These methods were validated statistically. The recovery studies confirmed the accuracy of the proposed methods.

A new, simple, sensitive spectrophotometric method in ultraviolet region has been developed for the determination of carvedilol in bulk and in pharmaceutical formulations. Carvedilol exhibited maximum absorbance at 285 nm with apparent molar absorptivity of 15.4x103 I/mol.cm in methanol. Beer's law was found to be obeyed in the concentration range of 4-36 μg/ml. Results of theanalysis were validated statistically and by recovery studies.

In vitro cytotoxic activity of some 2-(N-aryl/heteroaryl aminomethyl)-1,3-diphenyl/1-phenyl-3-(3- nitrophenyl)/1-phenyl-3-(pyridin-3-yl)propan-1,3-diones were determined by adopting three methods (Trypan blue dye exclusion, Lowry, MTT, 3-(4,5-dimethyl thiazol-2-y1)-2,5-diphenyl tetrazo- lium bromide assay) using HEp-2 cell cultures. Among the compounds tested the compound Vlll was found to be superior in its cytotoxicity in all the three methods.

For the past ten years, many individuals and institutions in lndia have recognized the importance of community pharmacists towards patient care in addition to their traditional role as drug dispensers. The purpose of this study is to investigate the current dispensing practices in various areas within a district of Tamilnadu, to identify the deficiencies vis-à-vis regulatory requirements and the interventions needed to enhance the image and status of community pharmacy practice. A surveillance study was performed in two phases. The person in-charge of a pharmacy was approached with a questionnaire and data on dispensing practices were collected through a structured interview. Workshops were conducted to provide interventions that have been identified during survey, to retail pharmacists who volunteered to participate in the workshops. The knowledge gained on completion of the workshop was assessed. The study found about 50% of the pharmacies function without pharmacists. Fifty eight percent pharmacists dispense prescription drugs without prescription. More than 80% of the retail pharmacists were not aware of rational drug use and have not even heard about transdermal patches. The retail pharmacists rarely counsel patients and examine the prescription for medical errors. Improvement in knowledge occurred among workshop attendees after the workshop. Guidelines have been compiled, which when implemented gradually, may provide impetus to community pharmacists in this area to perform the task of providing pharmaceutical services in a better and professional way.

A simple, efficient and reproducible method for the determination of gatifloxacin in tablets has been developed using reverse phase high performance liquid chromatographic method. The elution was done using a mobile phase consisting of 0.01N Na2HPO4 (pH 5.0) and acetonitrile (80:20% v/v) on Waters' Symmetry C18 4.6x150m m analytical column with flow rate of 1 ml/min with detection at 292 nm. An external standard calibration method was employed for quantitation. The elution time was 1.6 min. The linearity range was 5-30 μg/ml for gatifloxacin.

Amide conjugates of flurbiprofen with various amino acid methyl esters were synthesized by Schotten-Baumann technique using prodrug concept. Their physico-chemical characterization was carried out by analytical and spectral methods.They were subjected to in vitro hydrolysis in hydrochloric acid buffer (pH 1.2), phosphate buffer (pH 7.4) and 80% human plasma (pH 7.4).The amides were screened for analgesic, antiinflammatory and ulcerogenic activities. They showed comparable analgesic and antiinflammatory activities with appreciable decrease in the ulcer index. Amide conjugate of flurbiprofen with phenylalanine was found to be the most active, even more than the parent drug flurbiprofen.

Some imidazolines were synthesized from oxazolinones and upon treatment with benzaldehyde the Schiff's bases were synthesized from the respective imidazolinones. All these compounds were evaluated for analgesic, hypnotic and CNS depressant property and the LD50 of 4 campounds as representative of each series were determined. Some of the synthesized compounds were found to exhibit significant pharrnacodynamic properties.

A reproducible and sensitive method for estimation of amlodipine besylate in bulk drug and in its tablet formulations has been developed. The method is based on formation of a yellow colored ion pair with methyl orange in acidic medium. This method follows Beer's law and has a range of 1 to 10μg/ml.

Residues of dimethoate were analyzed in different grapes (paneer, green, seedless violet) and tomatoes (nattu and Bangalore). Analyses were performed by HPLC using a reversed-phase column (RP-18). Extractions from grapes and tomatoes were carried out with benzene. The residues found in grapes were lower than the admissible limits mentioned by FDA, whereas in case of tomatoes, the residues were found to exceed the limits prescribed by FDA to a slight extent.

A novel, simple, sensitive, rapid and spectrophotometric method has been developed for simultaneous estimation of amoxycillin trihydrate and rabeprazole sodium. The method involves solving of simultaneous equations based on measurement of absorbances at two wavelengths 247 nm and 292 nm. Both the drugs obey Beer's law in the concentration ranges employed for this method. Results of the method were validated statistically and by recovery studies.

An attempt was made to compare and assess the permeability characteristics of selected drug molecules by varying lipophilicity and molecular weight using in vitro diffusion assembly and everted small intestinal sac model. Apparent permeability coefficient, flux, permeability coefficient and enhancement ratio of selected drug molecules through both the models were compared. The permeation data was compared with physicochemical properties including solubility parameter of drug molecules. In vitro data was found to be higher than the data obtained from everted sac model. Permeation of drugs through everted sac model was significantly enhanced by incorporation of sodium taurocholate (1%), which could be correlated with in vitro diffusion data.

Studies were carried out on the stem bark of Ricinodendron heudelotii (Baill) Pierre ex Pax (Euphorbiaceae).The phytochemical examination of the n-hexane and methanol/methylene chloride extracts by silica gel chromatography afforded aleuritolic acid 1 and labda-8(17),13-dien- 3β,15-diol 2, which were isolated for the first time along with E-ferulic acid octacosylate 3. The structures were elucidated using spectroscopic methods. The antimicrobial activity of the n-hexane and MeOH/CH2Cl2 extracts evaluated using disc diffusion method showed that these extracts were more active against some of the microorganisms tested than some commercially available antibiotics used. For the eight microorganisms tested, the minimal inhibitory concentration (MIC) obtained varied from 4.6±1.2 to 22±4 mg/ml for the n-hexane extract and from 5.±21.2 to 20±1.5 mg/ml for the MeOH/CH2Cl2 extract. Streptococcus faecalis was found being the most susceptible organism with a MIC of 4.6 mg/ml for the n-hexane extract. These antimicrobial properties probably explain partly, the use of this plant in traditional medicine.

The aim of the present study was to investigate the sleep promoting effect of herbals and their interaction with GABAergic drugs. Pentobarbitone-induced hypnosis test was used in order to prove the above hypothesis. Seep latency and total sleep time were used as parameters for the evaluation. Ashwagandha (Withania somnifera) or BR-16A (Mentat®) potentiated the effect of triazolam (0.1 mg/kg, i.p.). However, ashwagandha did not produce any significant effect with alprazolam (0.25 mg/kg, i.p.). Also melatonin (5.0 mg/kg, i.p.) and buspirone (1.0 mg/kg, i.p.) did not produce any significant effect on sleep parameters along with ashwagandha or BR 16A (100mg/ kg, p.o., P<0.05). Sleep promoting effect of BR-16A might be due to presence of ashwagandha. Its combination with GABAergic drugs (triazolam and alprazolam,) suggested that these drugs have common mechanism in sleep promoting effect of pentobarbitone and could be used along with other GABAergic hypnotics for the treatment of insomnia. This may reduce the dose of the latter drug(s). BR-16A or ashwagandha can be used for the treatment of sleep and related disorders.

In the present study, the leaves of Garcinia xanthochymus (Guttiferae) was investigated for antiinflammatory activity using carrageenan-induced rat paw edema method. The results demonstrated that the equivalent percentage inhibition of petroleum ether extract and methanolic extract was 86.4 and 80.7%, respectively compared to standard ibuprofen, which is statistically significant.