Department of Chemical Engineering, National Tsing Hua University, Hsinchu 300044, Taiwan, ROC.
Langmuir. 2020 Dec 8;36(48):14782-14792. doi: 10.1021/acs.langmuir.0c02738. Epub 2020 Nov 25.
The assembly-disassembly of hyaluronic acid (HA) with a bovine serum albumin-conjugated gold nanoparticle (BSA-AuNP) was demonstrated using a gas-phase electrophoresis approach, electrospray-differential mobility analysis (ES-DMA). Physical sizes, number and mass concentrations, and degrees of aggregation of HA, BSA, and AuNP were successfully quantified using ES-DMA hyphenated with inductively coupled plasma mass spectrometry. Attenuated total reflection Fourier transform infrared (ATR-FTIR) spectroscopy was employed complementarily for an orthogonal characterization of the assembly of HA with BSA-AuNP and the subsequent HA detachment. The results show that the surface packing density of HA on BSA-AuNP was proportional to the concentration of HA () when ≤ 5 × 10 μmol/L, and the equilibrium binding constant of HA on BSA-AuNP was identified as ≈ 4 × 10 L/mol at pH 3. The pH-sensitive and enzyme-induced detachments of HA from BSA-AuNP were both successfully characterized using ES-DMA and ATR-FTIR. In the absence of enzymatic catalysis, the rate constant of HA detachment () was shown to increase by at least 3.7 times on adjusting the environmental acidity from pH 3 to pH 7. A significant enzyme-induced HA detachment was identified at pH 7, showing a remarkable increase of by at least two times in the presence of an enzyme. This work provides a proof of concept for assembly of HA-based hybrid colloidal nanomaterials through the tuning of surface chemistry in the aqueous phase with the ability of in situ quantitative characterization, which has shown promise for the development of a variety of HA-derivative biomedical applications (e.g., drug delivery).
利用气相电泳方法——电喷雾-差分迁移分析（ES-DMA），展示了透明质酸（HA）与牛血清白蛋白偶联金纳米粒子（BSA-AuNP）的组装-解组装过程。采用电喷雾-电感耦合等离子体质谱联用技术（ES-DMA-ICP-MS），成功地对 HA、BSA 和 AuNP 的物理尺寸、数目和质量浓度以及聚集程度进行了定量分析。衰减全反射傅里叶变换红外光谱（ATR-FTIR）分析技术被用来对 HA 与 BSA-AuNP 的组装及其随后的 HA 解组装进行正交表征。结果表明，当 ≤ 5 × 10 μmol/L 时，HA 在 BSA-AuNP 上的表面组装密度与 HA 的浓度呈正比，并且在 pH 3 时，HA 在 BSA-AuNP 上的平衡结合常数被确定为 ≈ 4 × 10 L/mol。利用 ES-DMA 和 ATR-FTIR 成功地对 HA 从 BSA-AuNP 的 pH 敏感和酶诱导的解组装进行了表征。在没有酶催化的情况下，将环境酸度从 pH 3 调节至 pH 7 时，HA 解组装的速率常数（）至少增加了 3.7 倍。在 pH 7 时，观察到明显的酶诱导的 HA 解组装，在酶存在的情况下，HA 的解组装速率至少增加了两倍。该工作提供了一个概念证明，即在水相通过表面化学的调谐来组装基于 HA 的杂化胶体纳米材料，并具有原位定量表征的能力，这为开发各种 HA 衍生物的生物医学应用（如药物输送）提供了希望。
