Bioadhesive sodium alginate microspheres of Metoprolol tartrate (MT) for intranasal systemic delivery were prepared to avoid the first-pass effect, as an alternative therapy to injection, and to obtain improved therapeutic efficacy in the treatment of hypertension and angina pectoris. The microspheres (Ms) were prepared using emulsification--cross-linking method. The formulation variables were drug loading, polymer concentration, cross-linking agent concentration, and cross-linking time. The Ms were evaluated for characteristics, like particle size, incorporation efficiency, swelling ability, in vitro bioadhesion, in vitro drug release, and in vivo pharmacodynamic performance in rabbits against isoprenaline-induced tachycardia. Treatment of in vitro data to different kinetic equations indicated matrix-diffusion controlled drug delivery from sodium alginate Ms. Polymer concentration, cross-linking agent concentration, and cross-linking time influenced the drug release profiles significantly. In vivo studies indicated significantly improved therapeutic efficacy of MT from Ms with sustained and controlled inhibition of isoprenaline-induced tachycardia as compared with oral and nasal administration of drug solution.

Adhatoda vasica (L.) (Acanthaceae) is used in the indigenous system of medicine in India. The alkaloid Vasicine was isolated from ethanolic extract of the leaves of A. vasica using column chromatography. Vasicine acetate was obtained by acetylation of Vasicine. Vasicine acetate exhibited good zone of inhibition against bacteria: 10 mm against E. aerogenes, 10 mm against S. epidermidis, and 10 mm against P. aeruginosa. Vasicine acetate showed minimum inhibitory concentration values against bacteria: M. luteus (125 μg/mL), E. aerogenes (125 μg/mL), S. epidermidis (125 μg/mL), and P. aeruginosa (125 μg/mL). The radical scavenging activity of Vasicine acetate was the maximum at 1000 μg/mL (66.15%). The compound showed prominent cytotoxic activity in vitro against A549 lung adenocarcinoma cancer cell line. Quantification of Vasicine and Vasicine acetate by HPLC-DAD analysis showed their contents to be 0.2293% and 0.0156%, respectively, on dry weight basis of the leaves. Vasicine acetate could be probed further in drug discovery programme.

The objective of our study was to prepare and evaluate osmotic matrix (OM) tablets of diclofenac sodium (DS). In vitro studies were done on USPXXIV dissolution apparatus II in different release medium. Surface characteristics of coating films and osmotic contribution of OM tablets also were studied. In vivo evaluation was carried out in 6 healthy human volunteers using HPLC method to assay plasma samples, and the results were compared with the performance of fabricated matrix and two commercial tablets of DS. Through in vitro drug release kinetics, using regression coefficient analysis and Peppas equation, different pharmacokinetic parameters and relative bioavailability were determined. OM tablets were found to provide more prolonged and controlled therapeutic plasma DS levels and also showed improved bioavailability in comparison to fabricated matrix and commercial tablets studied.

Aqueous polymer solutions that are transformed into gels by changes in environmental conditions, such as temperature and pH, thus resulting in in-situ hydrogel formation, have recently attracted the attention of many investigators for practical biomedical or pharmaceutical applications.1-3) Ketorolac tromethamine (KT) is a potent non-narcotic analgesic with moderate anti-inflammatory activity and clinical studies indicate that it has a single dose efficacy, greater than morphine for postoperative pain and has excellent applicability in the emergency treatment of pain (break through cancer pain) and in the treatment of migraine headache. However, this drug is not currently available as nasal formulation. With intranasal delivery, a drug is absorbed directly into the systemic circulation, bypassing the problems that occur with oral administration, including fast onset of therapeutic effect without the discomfort and inconvenience of an injection.Pectin is a plant-derived polysaccharide commonly used in foods and drugs. Solutions containing drug plus pectin can be stored as liquids, and form gels when applied to the nasal mucosa.4) Chitosan is a linear polysaccharide derived from crustacean shells and is currently being investigated for many pharmaceutical applications because of its biocompatibility and biodegradability characteristics. 5) These observations made an impetus to prepare and evaluate chitosan and pectin based gelling systems of KT. ExperimentalMaterials KT, chitosan (purified, viscosity grade 50) and pectin were gift samples from Ranbaxy (India), CIFT (India) and India Citrus Products Ltd. (India), respectively. Hydroxypropyl methylcellulose (HPMC K15) (Sigma-Aldrich India Ltd., India), glacial acetic acid (S.D. Fine Chem., India), hydrochloric acid (Qualigens Fine Chem., India), dihydrogen potassium orthophosphate (Glaxo, India) and sodium hydroxide (E. Merck, India) were purchased. Double distilled water was used. All other chemicals used were of analytical reagent grade. Dialysis membrane (Sigma-Aldrich), Digital pH meter (Toshniwal Pvt. Ltd., India) and Brook Field viscometer (Tokimec Co., Japan) were also used.Methods For preparation of pectin or chitosan based gelling systems (Table 1); drug was mixed with polymer solution prepared in distilled water or 0.1 M glacial acetic acid, respectively and pH was adjusted to 4. For the preparation of HPMC K15 incorporated gels, HPMC K15 was also added while preparing pectin/chitosan solution and rest of the procedures were the same.The pH, angular viscosity and drug content of the prepared gels were studied using digital pH meter, Brookfield viscometer and UV-VIS spectrophotometer (JASCO 7800, Tokyo) at 322 nm, respectively.Gelation Studies Gelation studies were carried out by following a reported method 6) in different pH buffers (pH 5.0, 6.0, 6.6, 7.4) and were assessed by visual examination.Gelation temperature and gel melting was assessed by a modified procedure 7) as follows: 2 ml aliquot of gel was transferred to test tubes, sealed with aluminium f...

The reaction of twenty four new synthetic banana hybrids were selected and evaluated for resistance to M. incognita under artificially inoculated pot conditions. Known susceptible (Grand Naine) and resistant (Yankambi KM5) banana varieties were included as reference cultivars. Responses of banana hybrids to M. incognita infection was assessed by the nematodes population in roots, number of galled roots, percentage of galled roots and root gall index on a scale of 1-5, where 0 = 0 galls and 5≥100 galls. The result showed that seven banana hybrids, H 904, H 911, H  921, H 924, H 926, H 943 and H 952 were found to be tolerance to M. incognita and the remaining were rated as moderate susceptible and susceptible. The total phenols, peroxidase, polyphenol oxidase, phenylalanine ammonia lyase chemical and enzyme contains in roots were higher in tolerance genotypes viz-a-vis susceptible ones.