Amino acid‐derived Poly(L‐Lysine) (p(LL)) microgel as a versatile biomaterial: Hydrolytically degradable,drug carrying,chemically modifiable and antimicrobial material

Here, a microgel of poly(_L‐Lysine) (p(LL)) from an amino acid, _L‐Lysine, was synthesized by microemulsion technique using AOT as surfactant in gasoline. The prepared p(LL) microgel was shown to be hydrolytically degradable at pH values of 5.4, 7.4, and 9 in phosphate buffer solution (PBS). The protonated p(LL) microgel was loaded with model drugs such as naproxen and riboflavin and found to release about 80% of loaded naproxen in 180 minutes and 70% of loaded riboflavin in about 120 minutes suggesting the potential of p(LL) microgels to act as fast drug delivery vehicles. Furthermore, p(LL) microgels were chemically modified with 1‐bromoethane (BE), 1‐bromooctane (BO), and 1‐bromoethylamine (BEA) to render antimicrobial capabilities. It was found that protonated p(LL) microgels had 29 ± 1 mm inhibition zone diameter for Pseudomonas aeruginosa ATCC 10145. Furthermore, minimum inhibition concentration (MIC) and minimum bactericidal concentration (MBC) values for Staphylococcus aureus ATCC 6538 were also calculated as 1 and 2.5 mg/mL concentrations, respectively, for protonated p(LL) microgels.