The stability of ZnO particles in bacterial cellulose and its potential application as wound dressing

Abstract

Event Abstract Back to Event The stability of ZnO particles in bacterial cellulose and its potential application as wound dressing Hai Lin1, Jiaping Zhang2, Yujiang Fan1 and Xingdong Zhang1 1 Sichuan University, National Engineering Research for Biomaterials, China 2 Southwest Hospital, Third Military Medical University, Institute of Burns, China Introduction: Bacterial cellulose (BC) films can be applied as wound dressing[1]. Loaded with metal or metal oxide particles, the BC films will be improved with anti-microbial property. However, to avoid the possible toxic and side-effect, the stability of loaded particles should be considered together with the updated performance. We investigated the stability of ZnO particles in BC network with or without modification by computer simulation and experimental study. The ZnO containing modified BC films were further characterized as wound dressing. Materials and Methods: The models of ZnO and BC with or without introduced side groups were established by Materials Studio. The interaction between ZnO and BC or modified BC were simulated to meet the convergence criteria. Accordingly, the adsorption energy (EAds) of the process and the interaction energy at steady state (EInt) could be calculated. Based on the computer simulation, BC was modified by maleic anhydride to prepare BC-MA. BC-MA was soaked in zinc acetate ethanol solution and then reacted with sodium hydroxide which was dissolved in ethanol. Following the adequately washing by deionized water, the outcome was lyophilized and further dried in oven to attain ZnO containing BC (BC-MA/ZnO). The stability of ZnO was evaluated by sterilizing BC-MA/ZnO and extracting in PBS, with further detection of ZnO content. The antimicrobial property of BC-MA/ZnO was assessed by oscillation method with Staphylococcus aureus (S.au) and Escherichia coli (E.coli). Results and Discussion: The results of computer simulation between ZnO and BC or BC-MA are shown as Fig.1. The result indicated that EAds and EInt between ZnO and BC-MA are 7.0 and 5.5 times higher than that between ZnO and BC. During the experimental study, the ATR FT-IR spectra prove the successful modification of BC-MA and SEM pictures show the morphology of BC-MA and presence of ZnO particles in BC-MA/ZnO, shown as Fig.2. The thermal gravimetric and atomic absorption spectroscopy analysis indicate the ZnO contents range from 3.48%-14.48%. The results of stability tests confirm the higher stability of ZnO in BC-MA network than that in BC, which is consistent with the theory calculation. The MTT assay indicates that BC-MA/ZnO exhibits no cytotoxicity. The antimicrobial tests demonstrate the BC-MA/ZnO has antimicrobial percent higher than 90% to S.au and 40% to E.coli, respectively. Fig. 3 shows the comparison results. Conclusions: The stability of ZnO particles in bacterial cellulose is enhanced by the introduction of side groups on the glucan molecule. Also, the BC-MA/ZnO films show satisfactory antimicrobial property with no cytotoxicity. Therefore, the improved BC-MA/ZnO films have potential application value as wound dressing. National Natural Science Foundation for Young Scientists of China (51403134); Application Technology Research and Demonstration Projects of Hainan Province China (SQ2014ZDXM0294)