title: Quaternized chitosan as an antimicrobial agent:  antimicrobial activity, mechanism of action and biomedical applications in orthopedics.
abstract: Chitosan (CS) is a linear polysaccharide with good biodegradability, biocompatibility and antimicrobial activity, which makes it potentially useful for biomedical applications, including an antimicrobial agent either alone or blended with other polymers. However, the poor solubility of CS in most solvents at neutral or high pH substantially limits its use. Quaternary ammonium CS, which was prepared by introducing a quaternary ammonium group on a dissociative hydroxyl group or amino group of the CS, exhibited improved water solubility and stronger antibacterial activity relative to CS over an entire range of pH values; thus, this quaternary modification increases the potential biomedical applications of CS in the field of anti-infection. This review discusses the current findings on the antimicrobial properties of quaternized CS synthesized using different methods and the mechanisms of its antimicrobial actions. The potential antimicrobial applications in the orthopedic field and perspectives regarding future studies in this field are also considered.
authors: Shanghai Key Laboratory of Orthopedic Implants, Department of Orthopedic Surgery, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200011, China. tingtingtang@hotmail.com.
authors: Honglue
authors: H
authors: Tan
authors: Rui
authors: R
authors: Ma
authors: Chucheng
authors: C
authors: Lin
authors: Ziwei
authors: Z
authors: Liu
authors: Tingting
authors: T
authors: Tang
mesh_terms: D000890:Anti-Infective Agents / Q000737:chemistry / Q000627:therapeutic use*; D048271:Chitosan / Q000737:chemistry / Q000627:therapeutic use*; D006801:Humans; D009985:Orthopedics; D000644:Quaternary Ammonium Compounds / Q000737:chemistry / Q000627:therapeutic use*
chemical_list: D000890:Anti-Infective Agents; D000644:Quaternary Ammonium Compounds; D048271:Chitosan