Biosynthesis and Characterization of Laccase Catalyzed Poly(Catechol)

Enzymatic polymerization of catechol was conducted batch-wise using laccase enzyme produced by the culture Trametes versicolor (ATCC 200801). The polymerization reaction was carried out in 1:1 (v/v) aqueous-acetone solution, buffered at pH 5.0 with sodium acetate (50 mM) in a sealed, temperature-controlled reactor at 25°C. The molecular weight of the produced polymer was determined with GPC. FT-IR, DSC, and TGA were employed to investigate the structure and thermal behavior of synthesized poly(catechol). It was found that catechol units were linked together with ether bonds and thermal stability of the catechol increased in the poly(catechol) polymeric structure effectively. The number average molecular weight of poly(catechol) was found as 813 ± 3 Da with a very narrow polydispersity value of 1.17 showing selective polymerization of catechol by the enzyme.     

P(4-vinyl pyridine) hydrogel use for the removal of UO(2)(2+) and Th(4+) from aqueous environments

4-vinyl pyridine (4-VP) based hydrogels with 2-hydroxyethylmetacrylate (HEMA) and magnetic composites were prepared and tested for use in the removal of UO(2)(2+) and Th(4+) ions from aqueous environments. It was found that the absorption of these metal ions from aqueous environments decreased with an increase in the amount of HEMA contained within p(4-VP-co-HEMA) hydrogels between 0.498?mmol for pure p(4-VP) and 0.027?mmol for pure p(HEMA). The characterization of the hydrogels was determined by swelling experiments, FT-IR and thermal analysis. The effects of initial metal ion concentration, hydrogel amount and the temperature of the medium on absorption of the ions were investigated. Langmuir and Freundlich isotherms were constructed for the absorption of UO(2)(2+) and Th(4+). Both isotherms demonstrated that these metal ions complied with monolayer absorption kinetics.     

Development of Urea Uptake and Release Studies Using N,N-Dimethylacrylamide/Maleic Acid/Citric Acid Based Macrogel

Journal of Polymers and the Environment - Recently, the use of polymers in agricultural and horticultural applications has been seen as a solution to reduce water consumption and excess fertilizer...     

Non-Metal Polymeric Bioparticles Based on Maleic Acid/Citric Acid as a Catalyst for H2 Generation from NaBH4

Journal of Polymers and the Environment - Novel metal-free catalysts were synthesized form maleic acid (MA) and citric acid (CA) based polymers for hydrogen generation form NaBH4....     

Application of Poly (Agar-Co-Glycerol-Co-Sweet Almond Oil) Based Organo-Hydrogels as a Drug Delivery Material

In this study, it was aimed to investigate the synthesis, characterization and drug release behaviors of organo-hydrogels containing pH-sensitive Agar (A), Glycerol (G), Sweet Almond oil (Wu et al. in J Mol Struct 882:107–115, 2008). Organo-hydrogels, which contained Agar, Glycerol and different amounts of Sweet Almond oil, were synthesized via the free-radical polymerization reaction with emulsion technique using glutaraldehyde or methylene bis acrylamide crosslinkers. Then, the degree of swelling, bond structures, blood compatibility and antioxidant properties of the synthesized organo-hydrogels were examined. In addition, Organo-hydrogels which loaded with Ceftriaxone and Oxaliplatin were synthesized with the same polymerization reaction and release kinetics were investigated. In vitro release studies were performed at media similar pH to gastric fluid (pH 2.0), skin surface (pH 5.5), blood fluid (pH 7.4) and intestinal fluid (pH 8.0), at 37 °C. The effects on release of crosslinker type and sweet almond oil amount were investigated. Kinetic parameters were determined using release results and these results were applied to zero and first-order equations and Korsmeyer-Peppas and Higuchi equations. Diffusion exponential was calculated for drug diffusion of organo-hydrogels and values consistent with release results were found.

     

Use of Coconut Oil-Based Organo-Hydrogels in Pharmaceutical Applications

Journal of Polymers and the Environment - In this study, six different organo-hydrogel containing Agar-Glycerol (AG) based Coconut Oil (CnO) were synthesized using different crosslinkers to ensure...