Molecular recognition in poly(epsilon-caprolactone)-based thermoplastic elastomers.

Eva Wisse; A J H Spiering; Ellen N M van Leeuwen; Raymond A E Renken; Patricia Y W Dankers; Linda A Brouwer; Marja J A van Luyn; Martin C Harmsen; Nico A J M Sommerdijk; E W Meijer

doi:10.1021/bm060688t

PubMed · 17154467

Molecular recognition in poly(epsilon-caprolactone)-based thermoplastic elastomers.

Eva Wisse·A J H Spiering·Ellen N M van Leeuwen·Raymond A E Renken·Patricia Y W Dankers·Linda A Brouwer·Marja J A van Luyn·Martin C Harmsen·Nico A J M Sommerdijk·E W Meijer

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Abstract

The molecular recognition properties of the hydrogen bonding segments in biodegradable thermoplastic elastomers were explored, aiming at the further functionalization of these potentially interesting biomaterials. A poly(epsilon-caprolactone)-based poly(urea) 2 was synthesized and characterized in terms of mechanical properties, processibility and histocompatibility. Comparison of the data with those obtained from the structurally related poly(urethane urea) 1 revealed that the difference in hard segment structure does not significantly affect the potency for application as a biomaterial. Nevertheless, the small differences in hard block composition had a strong effect on the molecular recognition properties of the hydrogen bonding segments. High selectivity was found for poly(urea) 2 in which bisureidobutylene-functionalized azobenzene dye 3 was selectively incorporated while bisureidopentylene-functionalized azobenzene dye 4 was completely released. In contrast, the incorporation of both dyes in poly(urethane urea) 1 led in both cases to their gradual release in time. Thermal analysis of the polymers in combination with variable temperature infrared experiments indicated that the hard blocks in 1 showed a sharp melting point, whereas those in 2 showed a very broad melting trajectory. This suggests a more precise organization of the hydrogen bonding segments in the hard blocks of poly(urea) 2 compared to poly(urethane urea) 1 and explains the results from the molecular recognition experiments. Preliminary results revealed that a bisureidobutylene-functionalized GRGDS peptide showed more supramolecular interaction with the PCL-based poly(urea), containing the bisureidobutylene recognition unit, as compared to HMW PCL, lacking this recognition unit.

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3T3 Cells Animals Biocompatible Materials Calorimetry, Differential Scanning Cell Division Elastomers Mice Microscopy, Atomic Force Models, Molecular Molecular Conformation Polyesters Surface Properties Thermodynamics Journal Article Research Support, Non-U.S. Gov't

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Eva Wisse, A J H Spiering, Ellen N M van Leeuwen, Raymond A E Renken, Patricia Y W Dankers, Linda A Brouwer, Marja J A van Luyn, Martin C Harmsen, Nico A J M Sommerdijk, E W Meijer. 2006. Molecular recognition in poly(epsilon-caprolactone)-based thermoplastic elastomers.. https://doi.org/10.1021/bm060688t

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