State Key Laboratory for Modification of Chemical Fibers and Polymer Materials, College of Materials Science and Engineering, Donghua University, Shanghai 201620, China.
State Key Laboratory for Modification of Chemical Fibers and Polymer Materials, College of Materials Science and Engineering, Donghua University, Shanghai 201620, China.
J Colloid Interface Sci. 2025 Jan 15;678(Pt C):89-100. doi: 10.1016/j.jcis.2024.09.098. Epub 2024 Sep 13.
Phototherapy has emerged as a potential treatment strategy for bacteria-infected wounds, but the inadequate bacteria-capturing ability and excessive damage to normal tissues from single phototherapy are huge limitations. To solve the issues, herein we report the design of chitosan-based hydrogel with bacteria capturing and combined photothermal/photodynamic sterilization functions. Such hydrogel is prepared by mixing chitosan (CS) as matrix, protoporphyrin (PpIX) as photosensitizer and polydopamine (PDA) as photothermal agent and then chemically cross-linking CS with glutaraldehyde. The resulting CS-PpIX-PDA hydrogel possesses a porous architecture (average pore porosity = 60.9 %), excellent swelling capabilities (swelling ratio = 1855 %) and rheological property (G' > G″). The hydrogel can effectively produce reactive oxygen species (ROS) under 660 nm light irradiation due to the photodynamic effect of PpIX. Owing to the presence of PDA, the hydrogel displays a photoabsorption range between 600 and 1500 nm and can generate maximal temperature of 60 °C within 10 min under 808 nm laser illumination (0.6 W/cm) through photothermal effect. Besides, under synergetic illumination of 808/660 nm laser, CS-PpIX-PDA hydrogel can induce the death of 99.9999 % of E. coli and 99.99999 % of S. aureus. Importantly, when coated on the wound site, the hydrogel exhibits a remarkable bacteria-trapping ability due to its porous structure and the presence of amino groups on chitosan. Under the excitation of 660/808 nm, the combined photothermal and photodynamic effects can effectively eradicate bacteria. Simultaneously, the hydrogel also demonstrates anti-inflammatory properties and upregulates Heat Shock Protein 90 (HSP90) expression, thereby promoting collagen deposition and facilitating wound healing. Therefore, the study may provide some new insights into the development of multifunctional hydrogel for photothermal-oxidation sterilization of bacteria-infected wound therapy.
光疗已成为治疗细菌感染伤口的一种有潜力的策略，但单一光疗对细菌的捕获能力不足和对正常组织的过度损伤是巨大的限制。为了解决这些问题，本文报道了一种基于壳聚糖的水凝胶的设计，该水凝胶具有细菌捕获和结合光热/光动力杀菌功能。该水凝胶是通过混合壳聚糖（CS）作为基质、原卟啉（PpIX）作为光敏剂和聚多巴胺（PDA）作为光热剂，然后用戊二醛化学交联 CS 制备而成。所得 CS-PpIX-PDA 水凝胶具有多孔结构（平均孔径孔隙率为 60.9%）、优异的溶胀性能（溶胀比为 1855%）和流变性能（G'>G″）。由于 PpIX 的光动力作用，水凝胶在 660nm 光照射下能有效地产生活性氧（ROS）。由于存在 PDA，水凝胶在 600nm 至 1500nm 之间具有光吸收范围，并能在 808nm 激光照射下（0.6W/cm）通过光热效应在 10min 内产生 60°C 的最大温度。此外，在 808/660nm 激光协同照射下，CS-PpIX-PDA 水凝胶能诱导 99.9999%的大肠杆菌和 99.99999%的金黄色葡萄球菌死亡。重要的是，当水凝胶涂在伤口部位时，由于其多孔结构和壳聚糖上的氨基，它表现出显著的细菌捕获能力。在 660nm/808nm 的激发下，光热和光动力的协同作用能有效地消灭细菌。同时，水凝胶还具有抗炎作用，并上调热休克蛋白 90（HSP90）的表达，从而促进胶原蛋白的沉积，促进伤口愈合。因此，该研究可能为开发用于光热氧化杀菌治疗细菌感染伤口的多功能水凝胶提供一些新的思路。
