N-acetylcysteine side-chain functionalization of poly(globalide-co-ε-caprolactone) through thiol-ene reaction

Mater Sci Eng C Mater Biol Appl. 2019 Jan 1:94:477-483. doi: 10.1016/j.msec.2018.09.060. Epub 2018 Sep 24.

Abstract

N-Acetylcysteine (NAC) is a drug well known for its antimucolytic action, antioxidant activity and ability to protect cells from oxidative stress. Conjugation of NAC with double bonds in the main polymer chain of poly(globalide-co-ε-caprolactone) (PGlCL) through thiol-ene reaction is reported. Different globalide (Gl) (an unsaturated macrolactone) to ε-caprolactone (CL) ratios were employed for PGlCL synthesis. The polymeric materials (PGlCL-NAC) were evaluated in terms of the number of functionalized double bonds, thermal properties, affinity for water and antioxidant potential. PGlCL-NAC containing more globalide repeating units presented higher degree of functionalization, due to the higher number of double bonds available to react through thiol-ene coupling. For high globalide contents (Gl/CL ratios above 50/50), NAC coupling in PGlCL chains resulted in completely amorphous copolymers with a more hydrophilic character, which should enhance bioresorption and cell adhesion characteristics. Functionalization also gave rise to a thioether linkage, conferring to PGlCL-NAC an antioxidant character, important for biomedical applications, where the material could combat cellular oxidative-stress.

Keywords: Globalide; N-acetylcysteine; Thiol-ene coupling; ε-Caprolactone.

MeSH terms

  • Acetylcysteine / chemical synthesis
  • Acetylcysteine / chemistry*
  • Antioxidants / pharmacology
  • Benzothiazoles / chemistry
  • Biphenyl Compounds / chemistry
  • Picrates / chemistry
  • Polyesters / chemical synthesis
  • Polyesters / chemistry*
  • Proton Magnetic Resonance Spectroscopy
  • Sulfhydryl Compounds / chemistry*
  • Sulfonic Acids / chemistry
  • Surface Properties

Substances

  • Antioxidants
  • Benzothiazoles
  • Biphenyl Compounds
  • Picrates
  • Polyesters
  • Sulfhydryl Compounds
  • Sulfonic Acids
  • polycaprolactone
  • 2,2'-azino-di-(3-ethylbenzothiazoline)-6-sulfonic acid
  • 1,1-diphenyl-2-picrylhydrazyl
  • Acetylcysteine