A coacervate-forming biodegradable polyester with elevated LCST based on bis-(2-methoxyethyl)amine. Issue 28 (27th June 2016)

• Record Type: Journal Article
• Authors: Swanson, J. P.; Martinez, M. R.; Cruz, M. A.; Mankoci, S. G.; Costanzo, P. J.; Joy, A.
• Is Part Of: Polymer chemistry. Volume 7:Issue 28(2016)
• Page Start: 4693
• Page End: 4702
• Publication Date: 2016-06-27
• Subjects: Polymers -- Periodicals; Macromolecules -- Periodicals; Polymerization -- Periodicals; 547.705
• DOI: 10.1039/c6py00814c
• Languages: English
• ISSNs: 1759-9954

Abstract

Abstract : This work details a thermoresponsive, biodegradable coacervate-forming polyester, which exhibits tunable T cp under various conditions. Abstract : Recently, we reported a new class of biodegradable, thermoresponsive polyesters (TR-PEs) inspired by polyacrylamides and elastin-like peptides (ELPs). The polyesters exhibit tunable cloud point temperatures ( T cp ) and thermoresponsive coacervation in aqueous solution as shown via UV-vis spectroscopy, 1 H NMR, and DLS. However, the T cp of all TR-PEs remained low (<15 °C), and higher thermoresponsivity would be beneficial for many applications. This study examines the synthesis, polymerization, and analysis of a new monomer bearing a more hydrophilic pendant group, bis-2-methoxyethylamine (bMoEtA). The resulting TR-PE, TR-bMoEtAPE, displays a threefold increase in T cp ( ca. 50 °C) that is affected by solution (DI water vs . phosphate buffered saline), concentration (1–40 mg mL −1 ) molecular weight (20–130 kDa), and cosolutes (Hofmeister salts and urea). The T cp and T g of randomTR-bMoEtAPE copolymers can be tuned via comonomer feed. Variable temperature 1 H NMR indicated a cooperative coacervation mechanism above T cp, further reinforced by DLS measurements. As evidenced by UV-vis and SEC analysis, TR-bMoEtAPE underwent rapid degradation over a period of 7 days in DI water and PBS. Finally, cytotoxicity studies suggested thatTR-bMoEtAPE is non-cytotoxic even at high concentrations ( ca. 1000 μg mL −1 ). The increased T cp and tunability suggestsTR-bMoEtAPE as a potential candidate for future functionalized TR-PE therapeutic-delivery systems.