Kappa-Carrageenan/PVA Filmswith Antibacterial Properties: Part 1. Optimization of Preparation Conditions and Preliminary Drug Release Studies

In this work, kappa carrageenan (KC) and poly(vinyl alcohol) are crosslinked with glutaraldehyde (GTA) to produce films without using catalyst HCL. The optimum conditions for the formation of film have been established based on their water absorption property. The crosslinking reaction was confirmed by FTIR analysis.The films were also characterized by scanning electron microscopy(SEM) and X-ray diffraction (XRD) analysis.The equilibrium swelling of films showed fair dependency on the presence of salt in the swelling medium.However, pH dependent swelling behavior was not prominent. Finally, a representative film sample was loaded with antibacterial drug Gentamicin sulphate and release was monitored kinetically in the physiological fluid (PF) at 37°C. The film showed fair antibacterial action against model bacteria E.Coli.     

Enhanced hydrogen selectivity from catalytic decomposition of formic acid over FeZnIr nanocatalyst at room temperature

Research on Chemical Intermediates - Hydrogen is considered a promising energy carrier for the future, especially for clean energy generation via fuel cell technologies. Formic acid is one of the...     

Nondispersive extraction for recovering lactic acid

Applied Biochemistry and Biotechnology - A nondispersive extraction process for recovery of lactic acid from fermentation broth is being developed. The criteria for selection of solvent,...     

Chemical interactions between aqueous and organic phases in a reactive extraction process

Partitioning of lactic acid between aqueous phase and kerosene containing trin-octyl phosphine oxide (TOPO) as a reactive agent was measured and analyzed in terms of an association model between lactic acid and TOPO. Equilibrium association was calculated to involve 1.1 mol of lactic acid/mol of TOPO.³¹P-NMR and FTIR analyses found no evidence of covalent bond formation between lactic acid and TOPO in solutions in kerosene, and pointed to hydrogen bond formation between the two chemicals. In a hydrophobic, microporous, hollow-fiber-membrane module, the simultaneous presence of lactic acid, TOPO, and the back-extractant NaOH resulted in drastic membrane fouling as evidenced by the loss of kerosene flux through the membrane. The membrane could be restored back to the original kerosene flux after extensive washing.

     

Preparation and Catalytic Application of Novel Water Tolerant Solid Acid Catalysts of Zirconium Sulfate/HZSM-5

Esterification of acrylic acid(AA) to produce AA esters has widespread application in the chemical industry. A series of water tolerant solid acid catalysts was prepared, and characterized by XRD, nitrogen adsorption, TGA-DTA, XPS, and ammonia adsorption FTIR. The effects of Si/Al ratio, zirconium sulfate(ZS) loading on HZSM-5 and calcination temperature on the esterification were investigated. When 20%(mass fraction) ZS is loaded on HZSM-5, the conversion of AA reaches 100%. XRD analysis indicates that ZS is highly dispersed on HZSM-5 because no crystalline structure assigned to ZS is found. Catalytic activity and hydrophobicity of ZS supported on HZSM-5 are higher compared with those of parent ZS or HZSM-5. Results show that this kind of novel catalysts is an efficient water tolerant solid acid catalyst for esterification reactions.     

Characterization of growth and enzymes produced by prt+lac+ and prt-lac-Lactococcus lactis cells

Applied Biochemistry and Biotechnology - Lactococcus lactis subsp.cremoris strains KH (prt+lac+) and KHA (prt?lac?) are used as starter cultures in manufacture of ripened cheeses. The...     

Application of thermogravimetric analysis for characterisation of bisdithiocarbamate of urea and its copper (II) complex

A novel disodium salt of bisdithiocarbamate of urea (UBDT) and its Cu(II) complex Cu(II)UBDT were prepared and characterised by elemental analysis, IR, electronic and NMR spectroscopy, conductivity measurements and thermogravimetric analysis (TGA). Water-soluble UBDT possessed good chelating ability for various metal ions. Its copper (II) complex, Cu(II)UBDT was amorphous, intractable solid having polymeric structure. The ligand as well as the complex was found to possess high thermal stability. UBDT cyclised on heating to yield a heterocyclic compound (“X”, probably highly stabilised by resonance) which also showed coordinating tendency for various metal ions.