Amphiphilic water soluble cationic ring opening metathesis copolymer as an antibacterial agent

Abstract

Bacterial infection is a global problem, especially resistance acquired by bacteria against to antibiotics; there is urgent need for the development of antibiotics. Here, we proposed dendron‐grafted polymers via ring opening metathesis polymerization (ROMP) featuring different with tailored hydrophobicity/hydrophilicity and cationic charges. Dendritic oxanorbornene derivatives were synthesized having two and six carbon linkers and their corresponding random and block copolymers were prepared having pendant pyridinium salt moieties via ROMP. In total, 12 different water‐soluble dendronized cationic polymers featuring hexyl pyridinium moieties were prepared and investigated. Six carbon linker possessing triple charge density and hexyl pyridinium functionality each repeating unit copolymers exhibited high antibacterial activity against Gram‐positive bacteria (S. aureus). However, all the polymers were inactive against Gram‐negative bacteria (E. coli). Most of the copolymers are non‐hemolytic (>HC 50 = 1,000 μg/ml). It was also observed that, there is no significant effect between block copolymers and random copolymers keeping hydrophobicity and cationic charge density constant. Zeta potential was measured to investigate the mechanism in solution via the interaction of polymers with S. aureus, while scanning electron microscope (SEM) measurements image confirms damage of the bacterial cell wall after implementation of biocidal polymer.

Metal adsorption properties of multi‐functional PAMAM dendrimer based gels

“…PAMAM G2 characterized according to the literature 27 . Shortly, FT‐IR spectra indicated that (data not shown), NH 2 peak of EDA at 3368 and 3284 cm −1 completely vanished after methyl acrylate Michael addition by appearing a new esteric carbonyl peak at 1731 cm −1 .…”

“…Presence of acrylamide repeating units might cause the swelling of Bare GEL 27 . Incorporation of amine functional group dendrimer (GEL G2‐1‐1) increased water adsorption to 427%.…”

“…PAMAM G2 characterized according to the literature. 27 Shortly, FT-IR spectra indicated that (data not shown), NH 2 peak of EDA at 3368 and 3284 cm À1 completely vanished after methyl acrylate Michael addition by appearing a new esteric carbonyl peak at 1731 cm À1 . PAMAM 0.00 was synthesized by the addition of EDA through amidation reaction which was confirmed by amide peak at 1635 and 1548 cm À1 .…”

“…Presence of acrylamide repeating units might cause the swelling of Bare GEL. 27 Incorporation of amine functional group dendrimer (GEL G2-1-1) increased water adsorption to 427%. However, GEL G2-2-1, GEL G2-2-2, GEL G2-3-1, and GEL G2-3-2 gels containing phosphonate and methacryl units resulted in higher swelling behavior in all gel series with a value of swelling 435%, 440%, 495%, 510%, and respectively.…”

Design of Aromatic Ring-Based Polyphosphonium Salts Synthesized via ROMP and the Investigation into Their Antibacterial and Hemolytic Activities

“…Here, zeta potential (ζ-potential) measurements were made by the dynamic light scattering (DLS) method to investigate the interaction between negatively charged bacterial membranes and cationic polymers to speculate about the mode of action of antimicrobial polymers. 29,34 First, we performed zeta potential and size values of the polymers in buffer to observe the formation of aggregate polymer itself to elucidate the relationship between polymer aggregation and antibacterial activity (Figure 3; for detailed information, see Table S3 and the graph in Figure S30). When 4c_10k, which has the lower activity against S. aureus (MIC =32 μg mL −1 ), was examined, it was seen that the zeta potential value was the highest (11 ± 0.63 mV) among the homopolymer series (Figure 3).…”