4 research outputs found
Formulation, Development and Evaluation of Fast Dissolving Oral Film of Antipsychotic Drug
In case of psychiatric treatment immediate release of drug from the dosage form is required. Fast dissolving dosage forms are gaining popularity in recent time, as this dosage forms requires no water for administration. Oral films dissolve rapidly along with drug in mouth and majority of the drug is absorbed through buccal/oral mucosa in to systemic circulation avoiding first pass metabolism. Olanzapine is a thienobenzodiazepine class of drugs, which has been approved by the FDA, for the treatment of schizophrenia, depressive episodes associated with bipolar disorder, acute manic episodes and maintenance treatment in bipolar disorder. The absolute bioavailability is only approximately 31.5% due to extensive hepatic metabolism. Thus the objective of the present study was to formulate and evaluate fast dissolving oral films of Olanzapine to improve water solubility, dissolution rate, oral bioavailability and reduction of first pass metabolism and increase patient’s compliance. Oral fast dissolving films prepared by solvent casting method using water and 95% ethanol as solvents and HPMC as film forming polymer. PEG 400 was the selected plasticizers, Superdisintegrants such as croscarmellose sodium (CCS) and sodium starch glycolate (SSG) alone and also in combinations was incorporated to achieve the aim. The prepared films were evaluated for the drug content, weight variation, film thickness, disintegration time, folding endurance, percentage of moisture content and in vitro dissolution studies. Among all, the formulation F4 was found to be best formulation which releases 98.78 % of the drug within 15 min and disintegration time is 42 sec. which was significantly high when compared to other formulation. The data obtained from In-vitro release were fitted into the various kinetic models such as Zero Order, Higuchi, First Order and Korsmeyer–Peppas Model in order to determine the mechanism of drug release. When the regression coefficient values compared, it was observed that ‘r’ values of formulation F4 was maximum i.e 0.974 hence indicating drug release from formulations was found to follow first order drug release kinetics.
 
Ab-initio study of free standing TiO2 clusters: Stability and magnetism
We report the structural behavior of nanoscale Titanium Dioxide (TiO2) clusters as well as their magnetic properties by varying the cluster size with the help of ground state geometries. The clusters of atomic scale rutile (TiO2)n, where n = 1-11, have been considered and geometrically stabilized through the Density Functional Theory as implemented in Vienna ab-initio Simulation Package. It is being observed that as the size of cluster increases from n = 2 to 11, the total energy decreases. The results of formation energy reveal the fact that as the cluster grows, it moves towards the stability and it is observed that n = 11 is the most stable structure. The stabilized clusters are different in geometries and co-ordination numbers. Finally, all the clusters have been investigated with self-consistent treatment of spin orbit coupling for magnetism studies. The magnetic properties of free clusters depict oscillatory behavior for magnetic moment with respect to the cluster size
Magnetoelectric Effect in L10-CoPd Thin Films
The effect of an applied electric field on the magnetic properties of L10-ordered CoPd thin films is investigated by first-principle calculations. Both the magnetic moment and the magnetocrystalline anisotropy of the surface atoms are changed by the electric field, but the net effect depends on the surface termination. The magnetocrystalline anisotropy switches from in-plane to perpendicular in the presence of external electric field. Typical magnetic-moment changes are 0.1 μBper eV/Å The main mechanism is the shift of the Fermi level, but the anisotropy change also reflects a crystal-field change due to incomplete screening
Magnetism of \u3ci\u3eL\u3c/i\u3e1\u3csub\u3e0\u3c/sub\u3e compounds with the composition \u3ci\u3eMT\u3c/i\u3e (\u3ci\u3eM\u3c/i\u3e = Rh, Pd, Pt, Ir and \u3ci\u3eT\u3c/i\u3e = Mn, Fe, Co, Ni)
The electronic band structure of ordered equiatomic compounds of 3d transition elements (Mn, Fe, Co, Ni) with nonmagnetic 4d and 5d elements (Rh, Pd, Pt, Ir) are investigated by linear muffin-tin orbital calculations. The systematic study considers 3d and 4d/5d spin moments and interatomic exchange interactions, with emphasis on the comparison between ferromagnetic and antiferromagnetic order. Total and site-resolved exchange interactions are calculated from first principles, and the obtained exchange constants are used to estimate ordering temperatures on a mean-field level