IRCCS-Fondazione Bietti, Rome, Italy.
Dipartimento di Scienze Chimiche, University of Catania, Catania, Italy.
Protein Sci. 2024 Apr;33(4):e4962. doi: 10.1002/pro.4962.
Insulin is commonly used to treat diabetes and undergoes aggregation at the site of repeated injections in diabetic patients. Moreover, aggregation is also observed during its industrial production and transport and should be avoided to preserve its bioavailability to correctly adjust glucose levels in diabetic patients. However, monitoring the effect of various parameters (pH, protein concentration, metal ions, etc.) on the insulin aggregation and oligomerization state is very challenging. In this work, we have applied a novel Surface Plasmon Resonance (SPR)-based experimental approach to insulin solutions at various experimental conditions, monitoring how its diffusion coefficient is affected by pH and the presence of metal ions (copper and zinc) with unprecedented sensitivity, precision, and reproducibility. The reported SPR method, hereby applied to a protein for the first time, besides giving insight into the insulin oligomerization and aggregation phenomena, proved to be very robust for determining the diffusion coefficient of any biomolecule. A theoretical background is given together with the software description, specially designed to fit the experimental data. This new way of applying SPR represents an innovation in the bio-sensing field and expanding the potentiality of commonly used SPR instruments well over the canonical investigation of biomolecular interactions.
胰岛素通常用于治疗糖尿病，在糖尿病患者的重复注射部位会发生聚集。此外，在其工业生产和运输过程中也会观察到聚集，应避免聚集以保持其生物利用度，从而正确调节糖尿病患者的血糖水平。然而，监测各种参数（pH 值、蛋白质浓度、金属离子等）对胰岛素聚集和寡聚状态的影响极具挑战性。在这项工作中，我们应用了一种新颖的基于表面等离子体共振（SPR）的实验方法，在各种实验条件下监测胰岛素溶液，以前所未有的灵敏度、精度和重现性监测其扩散系数如何受到 pH 值和金属离子（铜和锌）的影响。本报告的 SPR 方法，这是首次应用于蛋白质，除了深入了解胰岛素的寡聚和聚集现象外，还被证明非常适合确定任何生物分子的扩散系数。本文提供了理论背景和软件描述，专门用于拟合实验数据。这种应用 SPR 的新方法代表了生物传感领域的创新，大大扩展了常用 SPR 仪器的潜力，远远超出了对生物分子相互作用的典型研究。
