DEVELOPMENT OF OLANZAPINE LOADED PNA MICROGELS FOR DEPOT DRUG DELIVERY IN TREATMENT OF SCHIZOPHRENIA: IN VITRO AN IN VIVO RELEASE PROFILE.

Schizophrenia is a lifelong debilitating illness requiring extended treatment with antipsychotic agents. Non-adherence to therapy is a very common and severe problem in these patients, which can be improved by prescribing depot injectable or implant formulations. The purpose of this study was to develop PNA microgels based in situ gelling system for sustained release of olanzapine. PNA [poly(N-isopropylacrylamide-co-acrylic acid)] microgels were prepared using a previously developed method employing emulsion polymerization technique, applying one of the optimized formulations. Olanzapine loaded PNA microgels were characterized by viscosity measurements, cytotoxicity assay and TEM analysis. In vitro release of olanzapine from PNA microgels was determined on different pH and temperature range. In vivo studies were performed on male Sprague-Dawley rats with average weight of 315 g (n = 6). Olanzapine loaded PNA microgels were successfully prepared with drug loading efficiency of 2.14 ± 0.52%. The fluid like viscosity of microgels formulation at lower pH value (pH 5.0) and room as well as body temperature made it favorable for injection form. In vitro release was characterized by a high initial burst release up to 38.6% of the drug release within 2 h. In vivo release data also indicated similar initial high burst release that might indicate toxicity when administered in injectable dosage form but subcutaneous injection of PNA microgels proved fruitful results as this initial burst release followed a sustained release for 72 h. Hence, PNA microgels can be formulated for short term depot injection, which can potentially provide the release of olanzapine for 72 h.

Antimicrobial activity of fruits of Solanum nigrum and Solanum xanthocarpum.

Current study was conducted to investigate antimicrobial activity of fruit extracts of two Solanaceous plants (Solanum nigrum and Solanum xanthocarpum) found in Pakistan. Petroleum ether, chloroform, dichloromethane, ethyl acetate, acetone, methanol and water were utilized for extraction. The highest percentages of polar components of both the species were extracted by water; little amount of non-polar components by petroleum ether while very low quantities by other solvents. Antimicrobial activities were estimated by measuring zones of inhibition through hole-plate diffusion method, against three species of Gram positive bacteria, five species of Gram negative bacteria and three species of fungi selected for this study. Doses of 5, 10 and 15 mg/mL prepared through methanolic extracts of each plant's powdered fruit material displayed significant zones of inhibition against all three Gram positive bacteria, three of the Gram negative bacteria out of five and against all three fungi. Although these doses exhibited significant zones of inhibition but they are not as potent as standards: ampicillin or amphotericin B. The present study assures the possible potential of antimicrobial as well as antifungal activity of fruit extracts of these plants.

In vitro evaluation of transdermal patches of flurbiprofen with ethyl cellulose.

This study was aimed to determine effects of penetration enhancers and plasticizers on drug release from rationally designed formulations of flurbiprofen based transdermal drug delivery system. Matrix type transdermal patches were formulated with ethyl cellulose (EC) as a polymer by using plate casting method. The plasticizers such as propylene glycol (PG) and dibutyl phthalate (DBP), and enhancers such as Span 20, Tween 20, sodium lauryl sulfate (SLS), isopropyl myristate (IPM) and ethanol (EtOH) were formulated in different concentrations in the patches. Such different combinations of polymer with various enhancers and plasticizers in patches were evaluated for their effect on the physicochemical properties and drug release behavior of flurbiprofen. The drug release study was carried out by the paddle-over-disk method and permeation of drug was performed by Franz diffusion cell using rabbit skin. Patches having ethanol with ethyl cellulose showed more uniformity in the physical properties while the smoothness and clarity of patches containing sodium lauryl sulfate were not satisfactory. The drug release from patches followed Higuchi and Korsmeyer-Pappas model while maximum drug release was obtained by isopropyl myristate (903 microg). It was concluded that the patches having ethyl cellulose with isopropyl myristate and propylene glycol are more useful for transdermal patches of flurbiprofen.