Enzymatic degradation of poly(ether urethane) and poly(carbonate urethane) by cholesterol esterase

Christenson, Elizabeth M.; Patel, Sachin; Anderson, James M.; Hiltner, A.

doi:10.1016/j.biomaterials.2006.03.012

Cited by 121 publications

(97 citation statements)

References 31 publications

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“…Sensitivity of polyurethanes and their composites on hydrolytic conditions was estimated after their incubation in phosphate buffer solution (PBS, pH = 7.01) with sodium azide (as a bacteriostatic agent) for 36 weeks at 37 °C [26].…”

Section: Degradability In Hydrolytic Conditionsmentioning

confidence: 99%

“…Degradation of polymer samples in oxidative conditions was carried out in 20 % w/w hydrogen peroxide in 0.1 mol/dm 3 cobalt chloride solution (high reactive solution) for 16 weeks at 37 °C [26,27]. Because of the extremely reactive oxidative acting of H 2 O 2 /CoCl 2 [26] the incubation time was shorter than for the hydrolysis.…”

Section: Degradability In Oxidative Conditionsmentioning

confidence: 99%

“…Because of the extremely reactive oxidative acting of H 2 O 2 /CoCl 2 [26] the incubation time was shorter than for the hydrolysis.…”

Section: Degradability In Oxidative Conditionsmentioning

confidence: 99%

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Degradability of cross-linked polyurethanes/chitosan composites

et al. 2017

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Polyurethanes with synthetic poly([R,S]-3-hydroxybutyrate) in the soft segment and with polycaprolactone triol as cross-linker were blended with chitosan and degraded in hydrolytic and oxidative solutions. Progress of the degradation of the samples was evaluated by changes in their weight, surface topography and thermal properties. Increasing the poly([R,S]-3-hydroxybutyrate) content in soft segment as well as blending with chitosan resulted in an increase in degradability of cross-linked polyurethanes in both solutions.Keywords: cross-linked polyurethanes, chitosan, composites, polyurethane degradability. Podatność na degradację kompozytów usieciowanych poliuretanów z chitozanemStreszczenie: Poliuretany zawierające syntetyczny poli([R,S]-3-hydroksymaślan) w segmencie gięt-kim oraz polikaprolaktonotriol jako związek sieciujący zmieszano z chitozanem i poddano degradacji w roztworach hydrolitycznym i utleniającym. Postęp rozkładu kompozytów oceniano na podstawie zmiany masy, powierzchni i właściwości termicznych próbek. Zarówno zwiększenie zawartości poli([R,S]-3-hydroksymaślanu) w segmencie giętkim poliuretanów, jak i zmieszanie ich z chitozanem spowodowało wzrost podatności usieciowanych poliuretanów na degradację w obu rodzajach roztworów.Słowa kluczowe: usieciowane poliuretany, chitozan, kompozyty, podatność poliuretanów na degradację.Cross-linked polyurethanes (PUR) are mainly obtained in the reaction of isocyanates with polyols and low-molecular compounds, of which at least one type of reagent is multifunctional [1][2][3]. They can be also synthesized via reaction with using unsaturated compounds [4,5]. Cross-linked polyurethanes are not dissolved in the solvent but swelled. With an increase in the degree of cross-linking their elasticity decreases but stiffness increases. They are mainly used as coatings, membrane and shape memory materials [6].Cross-linked polyurethanes are generally less susceptible to degradation than linear polyurethanes. The presence of cross-linkages between chains of polyurethane significantly hinders the migration of water with enzymes, free radicals, and other degradative molecules into the polymer network [6].But, in some cases, the presence of a triol cross-linker in polyurethane structure leads to a polymer with no phase separation. Disordering of the polymer network and reduced mobility of the chains (as a result of chemical cross-linking) allow the ester/ether groups to be exposed to water. In this case cross-linked polyurethanes can be susceptible to degradation [7].The process of degradation of cross-linked polyurethanes can be accelerated by introducing the groups susceptible to degradation (such as ester groups) into their structure or by blending with degradable polymers. Natural polymers or their synthetic analogues (such as polyhydroxybutyrate, polycaprolactone, and chitosan) can be used as part of polyurethane network or as composite fillers.

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Section: Degradability In Hydrolytic Conditionsmentioning

confidence: 99%

Section: Degradability In Oxidative Conditionsmentioning

confidence: 99%

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Degradability of cross-linked polyurethanes/chitosan composites

et al. 2017

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“…5 mg) were incubated in phosphatebuffered saline (PBS) supplemented with glucose and containing suspended human red blood cells (RBCs) and hematocrit~5% (total volume of sample was 200 μL). Incubation was carried out at 37°C for up to 24 h. At the indicated time points (1,6,18, and 24 h), 40 μL of RBC suspensions was centrifuged (2500 g, 10 min) and the relative hemoglobin concentration in supernatants was monitored by measuring optical absorbance at 540 nm. 100% hemolysis was taken from samples in which 1% Triton X-100 was added to disrupt all the cell membrane and compared to the values obtained for negative control (RBCs suspension without polymers).…”

Section: Evaluation Of Hemocompatibilitymentioning

confidence: 99%

“…A relatively new generation of polyurethanes used in medical devices are based on poly(carbonate-urethane)s (PCUs). According to in vitro and early in vivo studies, PCUs exhibit improved resistance to hydrolytic degradation and in vivo stress cracking compared to oligoester based medical grade polyurethanes [17][18][19][20][21][22][23][24]. Furthermore, according to the mechanism of hydrolytic degradation of PCUs [25], a decrease of pH is not observed, which leads to a much lower inflammation of the surrounding tissues.…”

Section: Introductionmentioning

confidence: 99%

Assessment of aliphatic poly(ester-carbonate-urea-urethane)s potential as materials for biomedical application

et al. 2017

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Selected mechanical and biological properties of biodegradable elastomeric poly(ester-carbonate-urea-urethane)s (PECUUs) point towards their potential to be applied as scaffolds in tissue engineering. Here we explore their medical applicability taking into account their hemocompatibility and cytotoxicity. The influence of the ester monomer (derivatives of adipic and succinic acids), as well as diisocyanate type (IPDI and HDI) on the investigated PECUUs properties is presented. The presence of aliphatic diisocyanates, cyclic IPDI or linear HDI, governs the adhesion of Candida cells to these polymers offering the possibility to control the biofilm formation on their surface. In comparison to the linear form, cyclic diisocyanates with pentamethylene succinate or adipate fragments had two to three times lower biofilm mass formation on their surface. Reduced hemoglobin release from red blood cells observed during incubation of tested polymers with human erythrocytes suspension indicates their potential biocompatibility with human tissues. PECUUs were also able to support the growth of human keratinocytes HaCaT on their surface when coated with collagen. In effect, IPDI derivatives might possess a high potential for use in biomedical applications.

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Enzymatic Polymer Modification

Guebitz

2010

Biocatalysis in Polymer Chemistry

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Enzymatic degradation of poly(ether urethane) and poly(carbonate urethane) by cholesterol esterase

Cited by 121 publications

References 31 publications

Degradability of cross-linked polyurethanes/chitosan composites

Degradability of cross-linked polyurethanes/chitosan composites

Assessment of aliphatic poly(ester-carbonate-urea-urethane)s potential as materials for biomedical application

Enzymatic Polymer Modification

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