ADVANCES IN SOLID DISPERSION TECHNOLOGY AND ITS APPLICATIONS IN THE DEVELOPMENT OF SOLID DOSAGE FORMS

Amorphous solid dispersions are extensively used as a strategy for improving the bioavailability of poorly water - soluble compounds in past decade. Therefore, the application of this technique proves to be an important stratagem for pharmaceutical companies. However, the in - depth knowledge of the solid dispersion is desired for the scale up of formulation, from laboratory scale to industrial scale. Hydrophilic polymers are used for preparation of solid dispersion such as polyvinylpyrrolidone, hydroxylpropylmethylcellulose, polyethylene glycols. Recently some new carriers like cyclodextrins, gelucire, vitamin E TPGS and many more has been explored as a carrier for the solid dispersion technology. Using of these polymers has its own advantages and disadvantages. Method of preparation also influences dissolution profile of solid dispersion. In this review, we intend to discuss the recent advances in the field of solid dispersions and their use in multicomponent systems. This review also elaborates the method of preparation and its correlation with the in-vivo absorption properties. Keywords: Solid dispersion, Multicomponent systems, Hydrophilic carriers, BioavailabilityÂ

Spatiotemporal modeling of microbial metabolism

Background Microbial systems in which the extracellular environment varies both spatially and temporally are very common in nature and in engineering applications. While the use of genome-scale metabolic reconstructions for steady-state flux balance analysis (FBA) and extensions for dynamic FBA are common, the development of spatiotemporal metabolic models has received little attention. Results We present a general methodology for spatiotemporal metabolic modeling based on combining genome-scale reconstructions with fundamental transport equations that govern the relevant convective and/or diffusional processes in time and spatially varying environments. Our solution procedure involves spatial discretization of the partial differential equation model followed by numerical integration of the resulting system of ordinary differential equations with embedded linear programs using DFBAlab, a MATLAB code that performs reliable and efficient dynamic FBA simulations. We demonstrate our methodology by solving spatiotemporal metabolic models for two systems of considerable practical interest: (1) a bubble column reactor with the syngas fermenting bacterium Clostridium ljungdahlii; and (2) a chronic wound biofilm with the human pathogen Pseudomonas aeruginosa. Despite the complexity of the discretized models which consist of 900 ODEs/600 LPs and 250 ODEs/250 LPs, respectively, we show that the proposed computational framework allows efficient and robust model solution. Conclusions Our study establishes a new paradigm for formulating and solving genome-scale metabolic models with both time and spatial variations and has wide applicability to natural and engineered microbial systems

Design and synthesis of bio-based UV curable PU acrylate resin from itaconic acid for coating applications

UV curable PUA resin was successfully synthesized from polyol based on sustainable resource originated from itaconic acid (IA), isophorone diisocyanate (IPDI) and 2-hydroxyethyl methacrylate (HEMA). A polyol was synthesized by condensation reaction of IA with 16-hexanediol in the presence of p-Toluenesulfonic acid (pTSA). The synthesized PUA resin was characterized for its structural elucidation by using Fourier Transform Infrared Spectrophotometer (FTIR), 1H and 13C NMR spectroscopy. The synthesized UV curable PUA resin was incorporated in varying concentrations in conventional PUA coating system. The effects of varying concentration of synthesized UV curable PUA resin on rheology, crystallinity, thermal and coating properties were evaluated. The rheological behavior of the resins were evaluated at variable stress and result showed decrease in viscosity of resin as concentration of synthesized UV curable PUA resin increases in conventional PUA resin. The cured coatings have been evaluated for glass transition temperature (Tg) and thermal behavior by differential scanning calorimeter and thermogravimetric analysis respectively. The degree of crystallinity of the coatings was determined from X-ray diffraction patterns using the PFM program. It was found that increase in the mass proportion of IA based PUA in coatings, the coating becomes more rigid and crystalline. The synthesized UV curable PUA coatings showed interesting mechanical, chemical, solvent and thermal properties as compared to the conventional PUA. Further, cured coatings were also evaluated for gel content and water absorption

Some new records of parasites of rice stem-borers in India

The authors have recorded several parasites of paddy stem-borers in India, some of which were not known previously from this country while many others were known earlier only from other hosts. Some species of parasites recorded here are new to science. The new records mentioned include, Goniozus indicus and Perisierola sp. (Hym.: Bethylidae); Elasmus sp. and E. albopictus (Hym.: Elasmidae); Tetrastichus ayyari (Hym.: Eulophidae); ? Dicopulus sp. (Hym.: Mymaridae); Gen. nr.Habrocytus (Hym.: Pteromalidae); Trichogramma japonicum, T. sp. (notminutum), Trichogramma sp. (Hym.: Trichogrammatidae); Chelonus sp. 1, Chelonus sp. 2, Meteorus ? unicolor, Orgilus sp., Rhaconotus schoenobivorus, R. signipennis (Hym.: Braconidae); Amauromorpha accepta accepta, A. ? metathoracica, Apsilops sp., Isotima sp., Gen.et sp. indet. (Phaeogenini), Gen.et sp. indet. (Pimplini), Temelucha pestifer, T. sp. nr.pestifer, Temelucha sp. 1 and Temelucha sp. 2 (Hym.: Ichneumonidae); Telenomus dignus, T. rowani, T. sp. nr.rowani and T. (Aholcus) sp. (Hym.: Scelionidae) on Tryporyza incertulas; Trichospilus diatraeae (Hym.: Eulophidae), Apanteles pallipes and Tropobracon schoenobii (Hym.: Eulophidae), Apanteles pallipes and Tropobracon schoenobii (Hym.: Braconidae); Anilastus sp., Gen.et sp. indet. (Campoplegini), Coccygomimus laothoë and Devorgilla sp. (Hym.: Ichneumonidae) on Sesamia inferens; Apanteles baoris, R. signipennis and T. schoenobii (Hym.: Braconidae); A. a. schoenobii, Centeterus alternecoloratus var.?, Gen.et sp. indet. (Pimplinae), Pristomerus sp. and Temelucha sp. nr.basimacula (Hym.: Ichneumonidae) on Chilotraea auricilia; Apanteles flavipes and T. schoenobii (Hym.: Braconidae) on Chilotraea polychrysa and Apanteles sp. (group F) and R. schoenobivorus (Hym.: Braconidae) on Chilo suppressalis. New records of nematode parasites were:Agamermis sp. on T. incertulas, 5 new species of Hexamermis on T. incertulas and unidentified nematode species on C. auricilia, C. partellus, C. suppressalis and S. inferens