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Novel sodium alginate filled with polyaniline coated titanium dioxide [NaAlg–PANI (TiO 2 )] nanocomposite membranes were prepared by incorporating nanosized titanium dioxide modified with polyaniline into NaAlg matrix and crosslinked with glutaraldehyde. The developed membranes were assessed for intermolecular interactions using Fourier transform infrared (FTIR) to understand their interaction properties. Further, X-ray diffraction (XRD) studies were also performed to evaluate the morphology of the NaAlg mixed matrix membrane. The % degree swelling (DS) was calculated for all membranes in 1,4-dioxane/water mixtures at 30°C to know the correlation between pervaporation (PV) results and DS. The membranes were tested for suitability to dehydrate 1,4-dioxane by PV has been demonstrated. The effect of feed composition as well as amount of filler loading on PV separation performance of these membranes were evaluated in terms of flux and selectivity.

Mixed matrix polymer membranes containing nanosized (21 nm) TiO2 particles dispersed in sodium alginate (NaAlg) have been prepared by solution casting and cross-linking with glutaraldehyde. These membranes were tested for pervaporation (PV) dehydration of tetrahydrofuran (THF) and isopropanol from their aqueous solutions at 30°C. Results have been compared with plain cross-linked NaAlg membrane. Plain cross-linked NaAlg membrane could remove up to a maximum of 97 wt% of water at higher feed water concentrations of the feed with considerably much lower selectivity. Infinite selectivity values with reasonable fluxes were observed for the mixed matrix membranes of NaAlg in the investigated feed compositions of 5–15 wt% water containing THF and 10–20 wt% of water containing isopropanol feed mixtures. Fluxes of NaAlg-TiO2 mixed matrix membranes are slightly lower than those of plain the NaAlg membrane for the investigated range of feed water compositions.

Cellulose acetate butyrate-poly(vinyl pyrrolidone) (CAB-PVP) blend microspheres were prepared using the solvent evaporation technique using poly(vinyl alcohol) as an emulsifying agent. Atenolol (ATNL), an antihypertensive drug, was successfully loaded into these microspheres. Effect of experimental variables such as CAB/PVP ratio on ATNL encapsulation efficiency, release rate, size and morphology of the microspheres has been investigated. ATNL-loaded microspheres were analyzed using differential scanning calorimetry to investigate the crystalline nature of ATNL after encapsulation. DSC results indicated a non-uniform dispersion of ATNL in CAB-PVP blend matrix. Scanning electron micrographs indicated the formation of spherical microspheres. Mean particle size of the microspheres, as measured by the laser light scattering technique, ranged between 100 and 120 μm. An encapsulation of about 80% of ATNL was achieved. In vitro dissolution experiments performed in pH 7.4 buffer medium indicated the controlled re...

Blend microspheres of chitosan (CS) and guar gum (GG) have been prepared using the water-in-oil (w/o) emulsion method. Cefadroxil was loaded into the microspheres and cross-linked with glutaraldehyde, leading to the formation of a semi-interpenetrating polymer network (IPN) structure. The microspheres have been characterized by scanning electron microscopy, X-ray diffraction and differential scanning calorimetry. Scanning electron micrographs showed the formation of non-uniform microspheres with the rough surface. X-ray diffraction and differential scanning calorimetry studies of the plain and the drug-loaded microspheres indicated that drug is dispersed at the molecular level in the semi-IPN matrix. In vitro dissolution experiments performed in pH 7.4 buffer medium indicated a sustained and controlled release of cefadroxil from semi-IPN microspheres up to 10 h. The amount of drug loaded into microspheres, CS-GG composition of the blend and the amount of cross-linking agent used have shown dependencies on...