Enhanced water-solubility and antibacterial activity of novel chitosan derivatives modified with quaternary phosphonium salt

• Published in: Materials Science & Engineering C 2016-04, Vol.61, p.79-84
• Main Authors: Zhu, Dan, Cheng, Honghao, Li, Jianna, Zhang, Wenwen, Shen, Yuanyuan, Chen, Shaojun, Ge, Zaochuan, Chen, Shiguo
• Format: Article
• Language: English
• Subjects: Anti-Bacterial Agents - chemistry; Anti-Bacterial Agents - pharmacology; Antibacterial; Antibacterial materials; Antiinfectives and antibacterials; Aqueous solutions; Biomedical materials; Chitosan; Chitosan - chemistry; Chitosan - pharmacology; Derivatives; Escherichia coli; Escherichia coli - growth & development; Organophosphorus Compounds - chemistry; Organophosphorus Compounds - pharmacology; Quaternary phosphonium; Solubility; Staphylococcus aureus; Staphylococcus aureus - growth & development; Water solubility
• ISSN: 0928-4931; 1873-0191
• DOI: 10.1016/j.msec.2015.12.024

Chitosan (CS) has been widely recognized as an important biomaterial due to its good antimicrobial activity, biocompatibility and biodegradability. However, CS is insoluble in water in neutral and alkaline aqueous solution due to the linear aggregation of chain molecules and the formation of crystallinity. This is one of the key factors that limit its practical applications. Therefore, improving the solubility of CS in neutral and alkaline aqueous solution is a primary research direction for biomedical applications. In this paper, a reactive antibacterial compound (4-(2,5-Dioxo-pyrrolidin-1-yloxycarbonyl)-benzyl)-triphenyl-phosphonium bromide (NHS-QPS) was synthesized for chemical modification of CS, and a series of novel polymeric antimicrobial agents, N-quaternary phosphonium chitosan derivatives (N-QPCSxy, x=1–2,y=1–4) were obtained. The water solubilities and antibacterial activities of N-QPCSxy against Escherichia coli and Staphylococcus aureus were evaluated compare to CS. The water solubility of N-QPCSxy was all better than that of CS at neutral pH aqueous solution, particularly, N-QPCS14 can be soluble in water over the pH range of 3 to 12. The antibacterial activities of CS derivatives were improved by introducing quaternary phosphonium salt, and antibacterial activity of N-QPCSxy increases with degree of substitution. Overall, N-QPCS14 represents a novel antibacterial polymer material with good antibacterial activity, waters solubility and low cytotoxicity. N-quaternary phosphonium chitosan derivatives (N-QPCS) with different degrees of substitution were synthesized by introducing quaternary phosphonium salt that is synthesized via two step chemical reaction. Both antibacterial activities and solubility of N-QPCS were greatly improved comparing to that of chitosan. [Display omitted] •Preparation of novel chitosan derivatives bearing quaternary phosphonium (N-QPCS)•A new method for improving water-solubility and antibacterial activity of chitosan•Observing enhanced antibacterial activity against S. aureus and E. coli for N-QPCS•N-QPCS are obviously more soluble than chitosan at a wide pH range.•The antibacterial activities of N-QPCS are significantly better than that of chitosan.