Soft Tissue Response to the Presence of Polypropylene-G-Poly(ethylene glycol) Comb-Type Graft Copolymers Containing Gold Nanoparticles

The aim of this study is to evaluate the soft tissue response of the pure and Au-embedded PPg-PEG. PP-g-PEG2000, PP-g-PEG4000, Au-PP-g-PEG2000, and AuPP-g-PEG4000 were obtained via chlorination of polypropylene and polyethylene glycol in the presence of a base with a “grafting onto” technique. Solvent cast films of these four copolymers with PP as a control group were embedded into five different rats. After 30 days of implantation, microscopic evaluation of inflammation and SEM analysis were done. PP had the most intense inflammatory reaction among the other polymers. PP-PEG block copolymers with high molecular weight and gold-nanoparticles-embedded ones revealed mild inflammatory reaction independently. SEM assessment revealed punched hole-like defects on the surface of all polymer samples except for PP. Graft copolymers with PEG, especially Au-attached ones, have favorable soft tissue response, and inflammatory reaction becomes milder as the number of PEG side chains increases

Synthesis and characterization of polymeric linseed oil grafted methyl methacrylate or styrene

Syntheses of wholly natural polymeric linseed oil (PLO) containing peroxide groups have been reported. Peroxidation, epoxidation and/or perepoxidation reactions of linseed oil, either under air or under oxygen flow at room temperature, resulted in polymeric peroxides, PLO-air and PLO-ofl, containing 1.3 and 3.5 wt.% of peroxide, with molecular weights of 2100 and 3780 Da, respectively. PLO-air contained cross-linked film up to 46.1 wt.% after a reaction time of 60 d, associated with a waxy, soluble part (PLO-air-s) that was isolated with chloroform extraction. PLO-ofl was obtained as a waxy, viscous liquid without any cross-linked part at the end of 24 d under visible irradation and oxygen flow. Polymeric peroxides, PLO-air-s and PLO-ofl initiated the free radical polymerization of both methyl methacrylate (MMA) and styreine (S) to give PMMA-graft-PLO and PS-graft-PLO graft copolymers in high yields with M-w varying from 37 to 470 kDa. The polymers obtained were characterized by FT-IR. H-1 NMR, TGA, DSC and GPC techniques. Cross-linked polymers were also studied by means of swelling measurements. PMNA-graft-PLO graft copolymer film samples were also used in cell-culture studies. Fibroblast cells were well adhered and proliferated on the copolymer film surfaces, which is important in tissue engineering

New Vision of Science Departments in Our Universities

Science Departments of Faculty of Art and Sciences are closing this year in many Turkish Universities because of shortage of registered students. Tutorial task of stuff s working for these departments will decrease in 4-5 years. Th e teachers in these Universities will be busy with lectures to other departments. Th e service lectures of the teachers and the graduate students can make the teachers busy for a while. New future solutions for encouragement of the undergraduate students are being discussed

The effect of gold clusters on the autoxidation of poly(3-hydroxy 10-undecenoate-co-3-hydroxy octanoate) and tissue response evaluation

We describe the synthesis and characterization of gold clusters embedded into poly (3-hydroxy octanoate-co-3-hydroxy-10-undecenoate) (PHOU), and evaluated the tissue response of the material upon implantation onto muscle tissue (rat). For this aim, PHOU was obtained by Pseudomonas oleovorans from octanoic acid (OA) and 10-undecenoic acid (UA) with a weight ratio of 50:50. The unsaturated co-polyester film in which HAuCl4 was dispersed was exposed to air at room temperature to produce gold clusters embedded into cross-linked PHOU. The cross-linking kinetics of the gold catalyzed PHOU autoxidation was followed by sol-gel analysis. In vivo tissue reactions of the cross-linked PHOU embedded gold clusters were evaluated by subcutaneous implantation in rats. The rats appeared to be healthy throughout the implantation period. No symptom such as necrosis, abscess or tumor genesis was observed in the vicinity of the implants. Retrieved materials varied in their physical appearance after 6 weeks of implantation. AFM and SEM micrographs of the PHOU containing gold clusters were also taken. © 2010 Springer Science+Business Media B.V.2008-70-01-01 108T423Acknowledgement This work financially supported by grants from Zonguldak Karaelmas University Scientific Research Projects Commission grant# 2008-70-01-01 and TÜBİTAK grant# 108T423. The Authors wish to thank Kevin Cavicchi, Taner Erdoğan and Amitav Sanyal for their valuable discussions

Amphiphilic poly(3-hydroxy alkanoate)s: Potential candidates for medical applications

Poly(3-hydroxy alkanoate)s, PHAs, have been very attractive as biomaterials due to their biodegradability and biocompatibility. These hydrophobic natural polyesters, PHAs, need to have hydrophilic character particularly for drug delivery systems. In this manner, poly(ethylene glycol) (PEG) and hydrophilic functional groups such as amine, hydroxyl, carboxyl, and sulfonic acid have been introduced into the PHAs in order to obtain amphiphilic polymers. This review involves in the synthesis and characterization of the amphiphilic PHAs. Copyright © 2010 Baki Hazer

Amphiphiles from Poly(3-hydroxyalkanoates)

Polyhydroxyalkanoates (PHA) are biodegradable and biocompatible microbially produced natural polyesters. However, their hydrophobic character is a disadvantage for the direct use of these polyesters. The key to biocompatibility of biomedical implantable materials is to alter their surface in a way that minimizes hydrophobic interaction with the surrounding tissue. Therefore, hydrophilic groups have been introduced into PHA in order to obtain amphiphilic polymers. This chapter has focused on the chemically modified PHA with enhanced hydrophilic character as biomaterials for medical applications

Simple synthesis of amphiphilic poly(3-hydroxy alkanoate)s with pendant hydroxyl and carboxylic groups via thiol-ene photo click reactions

Biodegradable polymers gained worldwide attention among researchers because of environmental and petroleum reserve limitation issues. In this manner, poly (3-hydroxyalkanoate)s, PHAs, are very useful materials from the point of this view. They can be easily obtained by using several bacteria from renewable substrate such as sugar, plant oils and as well as synthetic chemicals. The improvement of their mechanical properties and enhance hydrophilic character are still main challenge of the polymer scientists. Herein we report the thiol-ene photo click reactions of the unsaturated medium chain length PHAs produced by using Pseudomonas oleovorans from 10-undecenoic acid, octanoic acid and/or soybean oily acids that are coded as poly(3-hydroxy undecenoate) (PHU), poly(3-hydroxy octanoate-co-undecenoate) (PHOU) and poly(3-hydroxy octanoate-co-soybean oil polymer) (PHOSy), respectively, in order to obtain their hydroxyl and carboxyl derivatives. The molecular weights of the modified PHAs obtained in this work were the same as those of the starting PHAs. Structural analysis of the PHA derivatives was performed by using 1H-, 13C, HMBC and HSQC NMR techniques. Melting and glass transitions of the hydroxyl and carboxyl derivatives of the microbial polyesters were found to be relatively higher than that of the starting unsaturated PHAs. © 2015 Elsevier Ltd. All rights reserved.Bülent Ecevit Üniversitesi Fundamental Research Fund of Shandong University: - 2012-10-03-13 211T016This work was supported by; both the Bülent Ecevit University Research Fund (#BEU- 2012-10-03-13 ) and TUBITAK (Grant # 211T016 ). The Authors thank to Mahmut Köse and İbrahim Demirtaş for their valuable discussion; Elvan Akyol for GPC measurements. Appendix

Amphiphilic poly(3-hydroxy alkanoate): potential candidates for medical applications

Poly(3-hydroxy alkanoate)s, PHAs, have been very attractive as biomaterials due to their biodegradability and biocompatibility. These hydrophobic natural polyesters, PHAs, need to have hydrophilic character particularly for drug delivery systems. In this manner, poly(ethylene glycol) (PEG) and hydrophilic functional groups such as amine, hydroxyl, carboxyl, and sulfonic acid have been introduced into the PHAs in order to obtain amphiphilic polymers. This review involves in the synthesis and characterization of the amphiphilic PHAs

The Properties of PLA/Oxidized Soybean Oil Polymer Blends

Novel polymer blends based on completely renewable polymers were reported. Polymer blends based on polylactic acid (PLA) and oxidized and hydroxylated soya bean oil polymers were prepared. Plasticization and mechanical strength effect of the soya bean oil polymers on the PLA were observed. Fracture surface analysis of the polymer blends was carried out by using scanning electron microscopy. The PLA blends showed more amorphous morphologies compared to pure PLA. The blends had better elongation at break in view of the stress-strain measurement. Blend of PLA with the hydroxylated polymeric soya bean oil indicated the slightly antibacterial properties. © 2014 Springer Science+Business Media New York.Bülent Ecevit Üniversitesi Fundamental Research Fund of Shandong University: -2012-10-03-13 211T016 PL-NSy-1-10Fig. 4 Stress-strain curves of polymer blends: a PLA-Cargill, b PL-PSyox-50-1, c PL-PSy-OH (PL-NSy-1-10), d PL-Plinox-1-42, e PL-PlinOH-2-13, f PL-Pentyn-1-52 Acknowledgments This work was supported by; both the Bülent Ecevit University Research Fund (#BEU-2012-10-03-13) and TUBI-TAK (Grant # 211T016). The Author thanks to Cem Berk for taking SEM micrographs, thanks to Özcan Cura (Cilas Kauc¸uk-Devrek), Ceyda Pembeci Kodolbas¸ (TÜBİTAK-MAM) for antibacterial analysis, Elvan Sulu and Timur S¸ anal for molecular weight measurements

Synthesis and properties of chitosan-modified poly (vinyl butyrate)

Modification of chitosan by grafting of vinyl butyrate was carried out in homogeneous phase using potassium persulfate as redox initator and 1.5% acetic acid as solvent. The percent grafting and grafting efficiency were analysed and the high grafting efficiency up to 94% was observed. The effects of reaction variables such as monomer concentration, initiator concentration, temperature and reaction time were investigated. It was observed that the solubility of chitosan was markedly reduced after grafting with vinyl butyrate. The grafted product is insoluble in common organic solvents as well in dilute organic and inorganic acids. Characterization of the graft copolymers were carried out by using Fourier Transform Infrared Spectroscopy (FTIR), Differential Scanning Calorimetry (DSC) and Scanning Electron Microscopy (SEM) technics. Characteristic signal of carbonyl group was observed at 1,731 cm(-1) which belongs to the poly vinyl butyrate segments in the graft copolymer. The melting transition of the chitosan main chain in the copolymer shifted to 124 degrees C from its original value 101 degrees C. In addition to these, we have also studied topology of the graft copolymer and the SEM micrograph showed continuous homogenous matrix which means there is no phase separation