Nematic - Isotropic Transition in Porous Media - a Monte Carlo Study

We propose a lattice model to simulate the influence of porous medium on the Nematic - Isotropic transition of liquid crystal confined to the pores. The effects of pore size and pore connectivity are modelled through a disorder parameter. Monte Carlo calculations based on the model leads to results that compare well with experiments.Comment: 11 pages; 4 figure

DEVELOPMENT OF SELF NANO-EMULSIFYING DRUG DELIVERY SYSTEM FOR AN ANTI-HYPERTENSIVE AGENT FELODIPINE: A SYSTEMATIC APPROACH FOR LIPID NANO-FORMULATION WITH IMPROVED ORAL BIOAVAILABILITY IN RATS

Objective: The present study involves the development of SNEDDS employing essential oils for enhancing biopharmaceutical performance. Methods: Preliminary investigations suggested the selection of cinnamon oil as an essential oil, tween 60 as a surfactant, while transcutol HP as a cosolvent for formulating SNEDDS. Formulations evaluated for stability, robustness to dilution, and emulsification time, droplet size, zeta potential (ζ), cloud point, in vitro drug release, drug excipient compatibility, TEM, stability assessment and in vivo pharmacokinetic performance in rats. Results: All formulations were robust, stable, and revealed excellent emulsification time<40 s, with fine droplet size (11.41±2.41 nm), lower PDI (0.028-0.277). Formulation F(FLD)6 exhibited a release of 97.7% within 4h, and TEM photograph confirmed spherical droplets. The bioavailability results revealed a higher rate and extent of absorption, AUC, and Cmax for the formulations found to be 1212.4 and 355.40±13.67 (p<0.05). The results recommend that the developed formulation approach offers bioavailability enhancement of FLD. Conclusion: The study concluded that SNEDDS would be an effective formulation system in increasing the aqueous solubility and potentially bioavailability. Furthermore, it can be applied for other therapeutic categories of drugs belonging to BCS class II and IV that show comparable biopharmaceutical challenges

New mixed ligand complexes of ruthenium(II) that incorporate a modified phenanthroline ligand: synthesis, spectral characterization and DNA binding

The hexafluorophosphate and chloride salts of two ruthenium(II) complexes, viz. [Ru(phen)(ptzo)2]2 and [Ru(ptzo)3]2+, where ptzo = 1,10-phenanthrolino[5,6-e]1,2,4-triazine-3-one (ptzo) - a new modified phenanthroline (phen) ligand, have been synthesised. These complexes have been characterised by infrared, UV-Vis, steady-state emission and1H NMR spectroscopic methods. Results of absorption and fluorescence titration as well as thermal denaturation studies reveal that both thebis- and tris-complexes of ptzo show moderately strong affinity for binding with calf thymus (CT) DNA with the binding constants being close to 105M-1 in each case. An intercalative mode of DNA binding has been suggested for both the complexes. Emission studies carried out in non-aqueous solvents and in aqueous media without DNA reveal that both [Ru(phen)(ptzo)2]2+ and [Ru(ptzo)3]2+ are weakly luminescent under these solution conditions. Successive addition of CT DNA to buffered aqueous solutions containing [Ru(phen)(ptzo)2]2+results in an enhancement of the emission. These results have been discussed in the light of the dependence of the structure-specific deactivation processes of the MLCT state of the metallo-intercalator with the characteristic features of its DNA interaction. In doing so, attempts have been made to compare and contrast its properties with those of the analogous phenanthroline-based complexes including the ones reported by us previously

Dehydrogenation of Isopropyl Alcohol on Zinc Molybdate (ZnMoO4)

851-85

Kinetics of Oxidation of Carbon Monoxide on Lanthanum Cobaltite

285-28

Catalytic Oxidation of Carbon Monoxide on Spinel Type Ferrites : Kinetic Characteristics

205-20

FORMULATION DEVELOPMENT AND EVALUATION OF SUSTAINED RELEASE GASTRORETENTIVE TABLET OF EMTRICITABINE

Objective: The study aims for the design and evaluation of floating tablets of emtricitabine (EMT), post oral administration to sustain the release and enhance gastric residence time (GRT). Methods: EMT is a nucleoside reverse-transcriptase inhibitor for the prevention and treatment of human immunodeficiency virus (HIV) infection. The investigation was considered to formulate a floating tablet of EMT with various agents. The formulation included with various concentrations of hydroxypropyl methylcellulose (HPMC) k4m, ethylcellulose, microcrystalline cellulose, polyvinylpyrrolidone (PVP) by wet granulation method. Various parameters for the prepared formulations were evaluated for weight variation, thickness, hardness, friability, floating lag time (FLT), total floating time (TFT), swelling index, in vitro drug release, and fourier-transform infrared spectroscopy (FTIR) studies. Results: The best formulation F1 exhibited 88.28% release in 24 h duration, with a floating lag time of 7 min and swelling index of 52.1% and drug content was determined to be 98.27%. The release mechanism was determined to be first order with higuchi release kinetics displaying diffusion along with the dissolution of the EMT from the tablet by non fickian mechanism. Conclusion: EMT tablets showed an increased GRT with a sustained release for 24 h thereby allowing a better window for absorption consequently improve the therapeutic effect of the drug