Hyperbranched Polyesters Based on Indole- and Lignin-Derived Monomeric Aromatic Aldehydes as Effective Nonionic Antimicrobial Coatings with Excellent Biocompatibility

Abstract

This research aims to investigate nonionic hyperbranched polyesters (HBPs) derived from indole and lignin resources as new nontoxic antimicrobial coatings. Three nonionic HBPs with zero to two methoxy ether substituents on each benzene ring in the polymer backbones were synthesized by melt-polycondensation of three corresponding AB 2 monomers. The molecular structures and thermal properties of the obtained HBPs were characterized by gel permeation chromatography, nuclear magnetic resonance spectroscopy, Fourier transform infrared spectroscopy, thermogravimetric analysis, and differential scanning calorimetry analyses. These HBPs were conveniently spin-coated on a silicon substrate, which exhibited significant antibacterial effect against Gram-negative ( Escherichia coli and Pseudomonas aeruginosa ) and Gram-positive bacteria ( Staphylococcus aureus and Enterococcus faecalis ). The presence of methoxy substituents enhanced the antimicrobial effect, and the resulting polymers showed negligible leakage in water. Finally, the polymers with the methoxy functionality exhibited excellent biocompatibility according to the results of hemolysis and MTT assay, which may facilitate their biomedical applications.

Nonionic nontoxic antimicrobial polymers: indole-grafted poly(vinyl alcohol) with pendant alkyl or ether groups

“…This suggested that the substitutions with alky (either linear or cyclic) groups on indole NH could decrease the hemocompatibility of the resulting polymers to some extent, while the substitutions with ether groups have no significant impact on the hemocompatibility, which is consistent with other reported polymers with ether groups. 90,91…”

“…(either linear or cyclic) groups on indole NH could decrease the hemocompatibility of the resulting polymers to some extent, while the substitutions with ether groups have no significant impact on the hemocompatibility, which is consistent with other reported polymers with ether groups. 90,91 Conclusions A new series of nonionic indole-based biodegradable poly (vinyl alcohol)s with different N-substituents were synthesized, which showed tuneable glass transition temperatures (39-93 °C) and desirable thermal stability. According to the disk diffusion assay, all these polymers showed effective antibacterial function against 9 different human pathogens.…”

Cholate-conjugated cationic polymers for regulation of actin dynamics

“…After 48 h of treatment, we studied the toxicity of the polymers using a 3-(4,5dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. 35 Protein purification G-actin was extracted from rabbit skeletal muscle acetone powder. 36 Actin was labeled with N-(1-pyrene) iodoacetamide (P-29, Molecular Probes).…”

Biocompatible non-leachable antimicrobial polymers with a nonionic hyperbranched backbone and phenolic terminal units

“…This could suggest that the ether or alkyl groups of phenolic HBPs could enhance their molecular interaction with the membrane of certain G(À) bacteria, which presumably could be related to their enhanced structural hydrophobicity. 64,95…”

“…by spin coating). 64 To our knowledge, the potential of dendritic polymers with phenol termini as new antimicrobial materials have not been investigated.…”