Resorbable elastomeric networks prepared by photocrosslinking of high-molecular-weight poly(trimethylene carbonate) with photoinitiators and poly(trimethylene carbonate) macromers as crosslinking aids

Bat, Erhan
Feijen, Jan
Grijpma, Dirk W.
Resorbable and elastomeric poly( trimethylene carbonate) (PTMC) networks were efficiently prepared by photoinitiated crosslinking of linear high-molecular-weight PTMC To crosslink PTMC films, low-molecular-weight PTMC macromers with methacrylate end groups were synthesized and used as crosslinking aids By exposing PTMC films containing only photoinitiator (Irgacure (R) 2959) or both photoinitiator and PTMC macromers to ultraviolet light. PTMC networks with high gel contents (87-95%) could be obtained The crosslink density could be readily varied by adjusting the irradiation time or the amount of crosslinking aid used. The formed networks were flexible, with low elastic modulus values ranging from 7.1 to 7.5 MPa, and also showed excellent resistance to creep in cyclic tests In vitro experiments showed that the photocrosslinked PTMC networks could be eroded by macrophages, and upon incubation in aqueous cholesterol esterase enzyme- or potassium dioxide solutions. The rate of surface erosion of photocrosslinked PTMC networks was significantly lower than that observed for films prepared from linear PTMC These resorbable PTMC elastomeric networks are compatible with cells and may find application in tissue engineering and controlled release. (C) 2011 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved


Synthesis, Characterization and Evaluation of Cytotoxic Activities of Novel Aziridinyl Phosphonic Acid Derivatives
Khan, Rehan; Ulusan, Sinem; Banerjee, Sreeparna; Doğan, Özdemir (Wiley, 2019-11-01)
New aziridine 2-phosphonic acids were prepared by monohydrolysis of the aziridine 2-phosphonates that were obtained by the modified Gabriel-Cromwell reaction of vinyl phosphonate or alpha-tosylvinyl phosphonate with a primary amine or a chiral amine. The cellular cytotoxicity of these compounds was tested against the HCT-116 colorectal cancer cell lines and the CCD-18Co normal colon fibroblast lines using the MTT assay. Three of the synthesized phosphonic acid derivatives 2e (ethyl hydrogen {(2S)-1-[(1S)-1-...
Comparison of Two Methods for Purification of Enterocin B, a Bacteriocin Produced by Enterococcus faecium W3
Dundar, Halil; ATAKAY, MEHMET; Celikbicak, Omuer; SALİH, BEKİR; Bozoglu, Faruk (Informa UK Limited, 2015-11-17)
This study aimed to compare two different approaches for the purification of enterocin B from Enterococcus faecium strain W3 based on the observation that the bacteriocin was found both in cell associated form and in culture supernatant. The first approach employed ammonium sulfate precipitation, cation-exchange chromatography, and sequential reverse-phase high-performance liquid chromatography. The latter approach exploited a pH-mediated cell adsorption-desorption method to extract cell-bound bacteriocin, ...
Enzymic activity of the K5-type yeast killer toxin and its characterization
Izgu, F; Altinbay, D; Sertkaya, A (Informa UK Limited, 2005-11-01)
K5-type yeast killer toxin secreted by P. anomala NCYC 434 cells has a broad killing spectrum. Competitive inhibiton of killer activity showed that glucans, mainly the beta-1,3 glucan, represent the primary toxin binding site within the cell wall of sensitive cells. Its hydrolytic activity on laminarin in an exo-like fashion revealed that the toxin exerts its killing effect by exo-beta-1,3-glucanase activity. Its specific activity on laminarin was 120U/mg, and the Michaelis constants K-m, and V-max for lami...
Selective oxidation and reduction reactions with cofactor regeneration mediated by galactitol-, lactate-, and formate dehydrogenases immobilized on magnetic nanoparticles
Demir, Ayhan Sıtkı; Talpur, Farah N.; Sopaci, S. Betul; Kohring, Gert-W; ÇELİK, AYHAN (Elsevier BV, 2011-04-10)
Rapid immobilization with the one-pot purification of galactitol dehydrogenase (GatDH) and formate dehydrogenase (FDH) is achieved by using iminodiacetic acid (IDA) with chelated Co2+ modified magnetic nanoparticles as a carrier. Lactate dehydrogenase (LDH) from recombinant Escherichia coli and FDH commencing Candida methylica were used as an auxiliary enzyme for the regeneration of NADH/NAD(+) with a representative synthesis of (S)-1,2-propanediol and L-tagatose starting from hydroxyacetone and galactitol....
Kinetic analyses of the effects of temperature and light intensity on growth, hydrogenm production and organic acid utilization by rhodobacter capsulatus
Sevinç, Pelin; Gündüz, Ufuk; Department of Biotechnology (2010)
Effects of temperature and light intensity on photofermentative hydrogen production by Rhodobacter capsulatus DSM1710 by use of acetic and lactic acids as substrates were studied. Experiments were conducted at 20, 30 and 38oC incubator temperatures under light intensities in the 1500 – 7000 lux range. pH of the medium and quantity of hydrogen forming together with quantity of biomass, and concentrations of acetic, lactic, formic, butyric and propionic acids in the medium were determined periodically. Growth...
Citation Formats
E. Bat, J. Feijen, and D. W. Grijpma, “Resorbable elastomeric networks prepared by photocrosslinking of high-molecular-weight poly(trimethylene carbonate) with photoinitiators and poly(trimethylene carbonate) macromers as crosslinking aids,” ACTA BIOMATERIALIA, pp. 1939–1948, 2011, Accessed: 00, 2020. [Online]. Available: