SELF-MICROEMULSIFYING DRUG DELIVERY SYSTEM

ABSTRACTOral route is the most convenient route of drug administration in many diseases and till today it is the first way investigated in the development ofnew dosage forms. The major problem in oral drug formulations is low and erratic bioavailability, which mainly results from poor aqueous solubility,thereby pretense problems in their formulation. More than 40% of potential drug products suffer from poor water solubility. For the therapeuticdelivery of lipophilic active moieties (biopharmaceutical classification system Class II drugs), lipid-based formulations are inviting increasingattention. Currently, a number of technologies are available to deal with the poor solubility, dissolution rate, and bioavailability of insoluble drugs.One of the promising techniques is self-microemulsifying drug delivery systems (SMEDDS). SMEDDS have gained exposure for their ability to increasesolubility and bioavailability of poorly soluble drugs. SMEDDS, which are isotropic mixtures of oils, surfactants, solvents, and co-solvents/surfactantscan be used for the design of formulations to improve the oral absorption of highly lipophilic drug compounds. Conventional SMEDDS are mostlyprepared in a liquid form, which can have some disadvantages. SMEDDS can be orally administered in soft or hard gelatin capsules and form finerelatively stable oil-in-water emulsions. Solid-SMEDDS are prepared by solidification of liquid/semisolid self-micron emulsifying ingredients intopowders, have gained popularity. This article gives a complete overview of SMEDDS, but special attention has been paid to formulation, design,evaluation, and little emphasis on application of SMEDDS.Keywords: Self-microemulsifying drug delivery system, Surfactant, Oil, Co-surfactant, Bioavailability, Lipophilic, Biopharmaceutical classificationsystem Class II drugs

INTEND, DEPICTION IN VITRO AND IN VIVO APPRAISAL OF GLIPIZIDE FLOATING MICROSPHERES USING ETHYL CELLLULOSE AND HYDROXYL PROPYL METHYL CELLULOSE AS POLYMER BY SUBSTANTIALLY MODIFIED METHOD

Objective: The purpose of this research was to formulate and evaluate floating microsphere of glipizide.Methods: Glipizide microsphere containing ethyl cellulose (EC) and hydroxyl propyl methyl cellulose (HPMC) were prepared by solvent evaporationmethod. Polymer to drug ratio affected characteristics of microspheres. Microspheres were discrete, spherical, and perforated form. The microspheresexhibited good floating property and achieved good gastric retention.Result: In vitro performance was evaluated by the usual pharmacopoeial and other tests such as drug polymer compatibility (Fourier transforminfrared scan), yield (%), micrometric properties such as tapped density (%). Compressibility particle size analysis (by optical microscopy), drugentrapment efficiency, surface topography (scanning electron microscope), and in vitro release study. On the basis of results, increasing the polymerratio increased the particle size (195.6±20.24 to 200.89±16.61), increased tapped density (maximum 0.29.60±0.00037 HGF4, batch), and decreased% compressibility (2.13±0.188). Drug loaded floating microspheres were found to be float more than 12 hrs on simulated gastric fluid (pH-1.2).Maximum drug entrapment was found in batch HGF3 (Drug:HPMC:EC) (1:1:3). Electron microscopy showed its perforated surface with hollowness.After 10 hrs, maximum release was found to be 78.0% (batch-GF1).Conclusion: The release study was performed in simulated gastric fluid with 0.02% tween80. The best release result was obtained at the ratio ofdrug: polymer (1:1).Keywords: Floating microspheres, Glipizide, Gastrorentensive system, In vitro release

Phytochemical Screening and Immunomodulator Activity of Mimusops elengi Linn.

Aim.  Phytochemical screening screening and investigation for immunomodulatory activity of ethanolic extract of leaves of Mimusops elengi using different parameters like carbon clearance, albumin globulin ratio, delayed type hypersensitivity reaction, total leukocyte count and estimation of immunoglobulin etc. Material and Methods. Ethanolic extract  of the plant leaves was  prepared. Preliminary phytochemical screening has been conducted. 1g of carragenan was dissolved in 100ml. of water for injection. 1% w/v suspension of carbon black as Indian ink. 2% PVP solution is prepared in water for injection. Four sets (A,B,C and D) of the animals were taken. Each set contains five groups and each group has six animals. After that different parameters of imunomodulation were performed. Result and Discussion. Phagocytic index was determined by measuring the concentration of Indian ink at different time intervals. The rate of Carbon clearance is a measure of Phagocytic activity, The result ( table 2 and  and fig 1) Suggested that in the case of control animals, the concentration of Indian ink obtained after 12 minuts of experimental time was decreased nearly 52% of its initial value as compared with the value recorded initially at 3 minuts. this decreased could be described of the natural course of phagocytosis to the particles by liver macrophages. on the other hand the ethanolic extract of the mimusops elengi  showed Significant immunostimulant activity as reflected by lower recovery of carbon particles as compared against that obtained by the control. the same trend was followed even after increasing the dose and the result were found to be directly influence by the increase in dose. Conclusion. The results of this study clearly indicate that the Ethanolic extract of M. elengi linn.leaves can be used as promising immunostimulating agents. The activity may be due to the presence of phytochemicals reported through phytochemical screening. Keywords:  Mimusops elengi, solvent extraction, carbon black as Indian ink

Selective binding of benzoquinone with a Pt^II-cyclophane constructed on the skeleton of<i style=""> N,N'</i>-bis(salicylidene)-<i style="">p</i>-phenylenediamine: Synthesis and spectroscopic studies

1644-1651The Schiff base N,N'-bis(salicylidene)-p-phenylenediamine has been complexed with Pt(en)Cl2 and the resulting PtII-cyclophane, [Pt(en)L]2·4PF6, reacted with phenol, resorcinol, hydroquinone or benzoquinone in DMSO solution. Their binding has been monitored by the variation in the corresponding UV-visible and emission spectral patterns. The binding properties are compared with the earlier reported ZnII-cyclophane [Zn(bpy)L]2 (bpy = 2,2'-bipyridine). A few solid adducts of phenol and benzoquinone with the PtII-cyclophane complex and hydroquinone as well as that of resorcinol with the Zn-cyclophane have also been synthesized and characterized

Formulation and evaluation of novel stomach specific floating microspheres bearing famotidine for treatment of gastric ulcer and their radiographic study

Objective: To develop and characterize multiple-unit-type oral floating microsphere of famotidine to prolong gastric residence time and to target stomach ulcer. Methods: The floating microspheres were prepared by modified solvent evaporation method. Eudragit S-100 was used as polymer. Microspheres were characterized for the micromeritic properties, floating behavior, entrapment efficiency and scanning electron microscopy. The in-vitro release studies and floating behavior were studied in simulated gastric fluid at pH 1.2. Different drug release kinetics models were also applied for all the batches. Selected formulations were also subjected for X-ray radiographic study. Results: Floating microspheres were successfully prepared by modified solvent evaporation technique. Microspheres showed passable flow properties. The maximum yield of microspheres was up to (95.11±0.35)%. On the basis of optical microscopy particle size range was found to be ranging from (52.18±182.00) to (91.64±5.16) μm. Scanning electron microscopy showed their spherical size, perforated smooth surface and a cavity inside microspheres. Microspheres were capable to float up to 20 h in simulated gastric fluid. X-ray radiographic studies also proved its better retention in the stomach. Conclusions: On the basis of the results, such dosage forms may be a good candidate for stomach targeting and may be dispensed in hard gelatin capsules

Reactivity of metal (Znˡˡ, Ruˡˡ)-2,2'-bipyridyl with some bifunctional ligands

1780-1786Complexation of cis-bis(2,2'-bipyridyl)dichlororuthenium(II) dihydrate with carboxaldehyde and carboxylate bearing ligand (4-carboxybenzaldehyde; L¹H) and with bis-acetyl and pyridine containing ligand (2,6-diacetylpyridine; L²) yields [Ru(bpy)₃](PF₆)₂ (bpy = 2,2'-bipyridyl), as the major product in both reactions along with [Ru(bpy)₂(L¹)]PF₆ (1) and [Ru(bpy)₂(L²)](PF₆)₂ (2) as minor products. However, reaction of cis-bis(2,2'-bipyridyl)dichlororuthenium(II) dihydrate with ligand containing bis-triazolo and diimino donor sites [1,4-bis(1,2,4–triazolo-3-imino)benzene; L³H₂] provides [Ru(bpy)₂Cl₂]PF₆ (3) crystals characterized by its single crystal X-ray data along with some unidentified product. Similar to ruthenium bipyridyl, reaction of (2,2'-bipyridyl)dichlorozinc(II) monohydrate with L² has also been carried out which yields [Zn(bpy)₃](PF₆)₂ as a crystalline product along with a polymeric product with the composition [{Zn(bpy)(L²)Cl₂}•DMSO] ո