Functional polymethacrylates as bacteriostatic polymers

Capsaicin-Inspired Thiol-Ene Terpolymer Networks Designed for Antibiofouling Coatings

Novel photocurable ternary polymer networks were prepared by incorporating N-(4-hydroxy-3-methoxybenzyl)-acrylamide (HMBA) into a cross-linked thiol-ene network based on poly(ethylene glycol)diacrylate (PEGDA) and (mercaptopropyl)methylsiloxane homopolymers (MSHP). The ternary network materials displayed bactericidal activity against Escherichia coli and Staphylococcus aureus and reduced the attachment of marine organism Phaeodactylum tricornutum. Extensive soaking of the polymer networks in aqueous solution indicated that no active antibacterial component leached out of the materials, and thus the ternary thiol-ene coating killed the bacteria by surface contact. The surface structures of the polymer networks with varied content ratios were studied by sum frequency generation (SFG) vibrational spectroscopy. The results demonstrated that the PDMS Si-CH₃ groups and mimic-capsaicine groups are predominantly present at the polymer-air interface of the coatings. Surface reorganization was apparent after polymers were placed in contact with D₂O: the hydrophobic PDMS Si-CH₃ groups left the surface and returned to the bulk of the polymer networks, and the hydrophilic PEG chains cover the polymer surfaces in D₂O. The capasaicine methoxy groups are able to segregate to the surface in an aqueous environment, depending upon the ratio of HMBA/PEGDA. SFG measurements in situ showed that the antibacterial HMBA chains, rather than the nonfouling PEG, played a dominant role in mediating the antibiofouling performance in this particular polymer system.

RAFT polymerization of bromotyramine-based 4-acryloyl-1,2,3-triazole: a functional monomer and polymer family through click chemistry

A series of bromotyramine-based 4-acryloyl-1,2,3-triazole monomers and polymers using click chemistry and RAFT polymerization.

Molecular interaction of a new antibacterial polymer with a supported lipid bilayer measured by an in situ label-free optical technique

The interaction of the antibacterial polymer-branched poly(ethylene imine) substituted with quaternary ammonium groups, PEO and alkyl chains, PEI25QI5J5A815-with a solid supported lipid bilayer was investigated using surface sensitive optical waveguide spectroscopy. The analysis of the optogeometrical parameters was extended developing a new composite layer model in which the structural and optical anisotropy of the molecular layers was taken into consideration. Following in situ the change of optical birefringence we were able to determine the composition of the lipid/polymer surface layer as well as the displacement of lipid bilayer by the antibacterial polymer without using additional labeling. Comparative assessment of the data of layer thickness and optical anisotropy helps to reveal the molecular mechanism of antibacterial effect of the polymer investigated.

The sustainable shape recovery of polyurethane copolymer grafted with pendant anthryl group under extremely low temperature conditions

The impact of the pendant anthryl group on the low temperature flexibility and tensile properties of a polyurethane block copolymer was investigated. The pendant anthryl group was designed to interrupt molecular interactions and to disturb the close contact between polyurethane (PU) chains through its rigid aromatic rings; thus, to improve the flexibility at extremely low temperatures, while maintaining high and reproducible tensile properties and the shape recovery at ambient temperatures. The attachment of the anthryl group was confirmed using the infrared (IR), nuclear magnetic resonance (NMR), and ultraviolet-visible (UV-VIS) spectroscopy. Increasing the anthryl content led to an unusual increase in the crosslink density due to partial crosslinking by the grafting reagent. The shape recovery and retention results were reproducible after performing repeated shape memory tests. Finally, the effect of the anthryl group on the shape recovery at −30 °C was compared with that of linear PU, and the reason for the remarkable flexibility at low temperature is discussed.

Studies of a furanoside as antimycobacterial agent loaded into a biodegradable PBAT/sodium caseinate support

An improved synthesis of n-octyl β-D-galactofuranoside was described using micro-wave activation. The resulting alkyl furanoside showed antibacterial activity against Mycobacterium smegmatis, a non-pathogenic model of Mycobacterium tuberculosis. It was further incorporated into a biodegradable PBAT/sodium caseinate polymer. The resulting biomaterial loaded with 5% of the pharmacophore retained the mycobacteriostatic properties and developed a mycobactericidal activity on contact and at the periphery of the film.