Improving the Antibacterial Properties ofW et Leather Based on Grafting - Cyclodextrin and Inclusion with Ciprofloxacin Hydrochloride

To improve the antibacterial properties of wet leather, a solution was proposed by using the Substance-Field model and the Standard Solutions in TRIZ, which involved grafted beta-cyclodextrin (beta-CD) with the inclusion of an antibacterial agent. beta-CD modified wet leather was prepared by the Schiff base reaction between the aldehyde group of the 6-position multi-aldehyde beta-CD derivative (MACD) and the amino group of the collagen fibres of the three kinds of wet leather/skin i.e. bated pelts, wet-white and wet-blue. Ciprofloxacin hydrochloride (CH), as a model antibacterial agent, was included in the cavity of beta-CD on the modified wet leather and its antibacterial effect against E. coli and S. aureus was investigated. The structure and properties of the wet crust leather grafted by beta-CD and with CH included were characterised by Fourier transform infrared (FTIR), ultraviolet-visible spectroscopy (UV-vis), differential scanning calorimetry (DSC), thermogravimetric (TG), and scanning electron microscopy (SEM). The results showed that the T-s of the three wet specimens after MACD treatment increased by 7.2 +/- 0.4 degrees C, 5.7 +/- 0.2 degrees C and 0.9 +/- 0.3 degrees C, the T-d increased by 8.0 degrees C, 4.9 degrees C and 0.9 degrees C, and the T-p increased by 5.8 degrees C, 6.9 degrees C and 3.9 degrees C, respectively. After treatment by CH after 90 days of storage, the antibacterial rates against E. coli still reached 99.7%, 99.8%, and 100%, respectively, which were 30.7%, 29.9%, and 25.4% higher than those without beta-CD treatment; and the antibacterial rates against S. aureus were 97.4%, 97.4% and 99.1%, respectively, which were 36.9%, 34.4% and 26.9% higher than those without beta-CD treatment, results which could meet the storage requirements of wet crust leathers in production. In conclusion, our solution could improve the longterm antibacterial performance and heat resistance of wet crust leathers and be expected to be applied to the leather industry.