Hudek Magdalena, Johnston Karen, Kubiak-Ossowska Karina, Ferro Valerie A, Mulheran Paul A
Department of Chemical and Process Engineering, University of Strathclyde, 75 Montrose Street, Glasgow G1 1XJ, U.K.
ARCHIE-WeSt, Department of Physics, University of Strathclyde, 107 Rottenrow East, Glasgow G4 0NG, U.K.
J Phys Chem C Nanomater Interfaces. 2024 Dec 10;128(50):21531-21538. doi: 10.1021/acs.jpcc.4c05821. eCollection 2024 Dec 19.
Chitosan is a nontoxic biopolymer with many potential biomedical and material applications due to its biodegradability, biocompatibility, and antimicrobial properties. Here, fully atomistic molecular dynamics simulations and enhanced sampling methods have been used to study the adsorption mechanism of chitosan oligomers on a silica surface from an aqueous solution. The free energy of adsorption of chitosan on a silica surface was calculated to be 0.6 kcal mol per monomer in 0.15 mol L aqueous solution, which is comparable to at room temperature. The loading capacity of chitosan on the silica surface was found to be 0.094 mg m, and it is dominated by charge compensation. Furthermore, the hydrogen bonding between chitosan and silica was analyzed. The nitrogen and hydroxyl group oxygen chitosan atoms were found to be the main contributors to the hydrogen bonding between chitosan and silica. These findings have the potential to guide the experimental design of chitosan-coated silica nanoparticles for applications such as drug delivery or additives for biopolymer food packaging.
壳聚糖是一种无毒的生物聚合物，因其具有生物可降解性、生物相容性和抗菌特性，在许多潜在的生物医学和材料应用领域具有重要价值。在此，我们运用全原子分子动力学模拟和增强采样方法，研究了壳聚糖低聚物在水溶液中于二氧化硅表面的吸附机制。在0.15 mol/L的水溶液中，计算得出壳聚糖在二氧化硅表面的吸附自由能为每单体0.6千卡/摩尔，这与室温下的情况相当。研究发现壳聚糖在二氧化硅表面的负载量为0.094毫克/平方米，且电荷补偿起主导作用。此外，还分析了壳聚糖与二氧化硅之间的氢键。结果发现壳聚糖中的氮原子和羟基氧原子是壳聚糖与二氧化硅之间氢键的主要贡献者。这些研究结果有可能为壳聚糖包覆二氧化硅纳米颗粒的实验设计提供指导，用于药物递送或生物聚合物食品包装添加剂等应用领域。
