Effect of zwitterionic polymers on wound healing

The effect of a thin film of a zwitterionic random copolymer composed of carboxybetaine [1-carboxy-N,N-dimethyl-N-(2′-methacryloyloxyethyl) methanaminium inner salt] (CMB) and n-butyl methacrylate (BMA), poly(CMB-r-BMA) (CMB, 30 mol%), on the healing of a full-thickness excisional and incisional wound in hairless rats was examined. The poly(CMB-r-BMA) film significantly enhanced wound closure and complete healing of a full-thickness excisional wound compared with the effect of the poly(n-butyl methacrylate) (PBMA) and the poly(ethylene terephthalate) (PET) films. However, the poly(CMB-r-BMA) film did not enhance healing of a fullthickness incisional wound in hairless rats. The amount of proteins adsorbed and that of neutrophiles adhered onto the poly(CMB-r-BMA) film were significantly smaller than those onto the PBMA and PET films. The results suggested that various cells and growth factors in the wound exudate are utilized effectively by covering an excisional wound with the poly(CMB-r-BMA) film, resulting in acceleration of healing. In addition, the poly(CMB-r-BMA) film significantly enhanced healing of a full-thickness excisional wound in hairless rats compared with the effect of Tegaderm® as wound dressings. The poly(CMB-r-BMA) film has potential as a new wound dressing.