International Innovation Center for Forest Chemicals and Materials and Jiangsu Co-Innovation Center for Efficient Processing and Utilization of Forest Resources, Nanjing Forestry University, Nanjing 210037, China.
International Innovation Center for Forest Chemicals and Materials and Jiangsu Co-Innovation Center for Efficient Processing and Utilization of Forest Resources, Nanjing Forestry University, Nanjing 210037, China.
Int J Biol Macromol. 2021 Dec 15;193(Pt B):1209-1214. doi: 10.1016/j.ijbiomac.2021.10.158. Epub 2021 Oct 30.
It is of crucial importance to know the quality of ultrathin films deposited on surface plasmon resonance (SPR) sensors prior to adsorption experiments. In this study, the optical properties of ultrathin cellulose nanocrystal films with various polymorphs (cellulose I, cellulose II and the hybrid of cellulose I/II), which deposited on gold surface of SPR sensors, were determined by a two-medium SPR technique and the influences of the second medium were assessed as well. The measured refractive index for ultrathin cellulose nanocrystal films with polymorphs of cellulose I, I/II and II was 1.453, 1.462 and 1.464, respectively, with a low margin of error about 0.2%. The porosity of according CNC films on SPR sensors was assessed to be 20.8%, 19.0%, and 18.5%. The measured film thickness for all deposited cellulose nanocrystal films was in the range of 25-35 nm, with a margin of error about 5%, accorded well with that examined by quartz crystal microbalance. The results showed that SPR surveys combined with Winspall analysis allow for simultaneous determination of the thickness, refractive index and the derived porosity, and provide a facile in situ quality control for the modified SPR sensors prior to adsorption experiments.
在进行吸附实验之前，了解沉积在表面等离子体共振（SPR）传感器上的超薄膜的质量至关重要。在这项研究中，通过双相 SPR 技术确定了沉积在 SPR 传感器金表面上的具有不同多晶型（纤维素 I、纤维素 II 和纤维素 I/II 混合物）的超薄纤维素纳米晶体薄膜的光学性质，并评估了第二相的影响。纤维素 I、I/II 和 II 多晶型的超薄纤维素纳米晶体薄膜的测量折射率分别为 1.453、1.462 和 1.464，误差幅度约为 0.2%。根据 SPR 传感器上的 CNC 薄膜的孔隙率评估为 20.8%、19.0%和 18.5%。所有沉积的纤维素纳米晶体薄膜的测量厚度均在 25-35nm 范围内，误差幅度约为 5%，与石英晶体微天平的检查结果吻合良好。结果表明，SPR 调查与 Winspall 分析相结合，可同时确定厚度、折射率和衍生的孔隙率，并为吸附实验之前的改性 SPR 传感器提供简便的原位质量控制。
