Interuniversity Microelectronics Center (IMEC), NEXT- Functional Nanosystems, Kapeldreef 75, B-3001 Leuven, Belgium.
Anal Chem. 2009 Nov 15;81(22):9425-32. doi: 10.1021/ac901822w.
Dynamic light scattering (DLS) is an analytical tool used routinely for measuring the hydrodynamic size of nanoparticles and colloids in a liquid environment. Gold nanoparticles (GNPs) are extraordinary light scatterers at or near their surface plasmon resonance wavelength. In this study, we demonstrate that DLS can be used as a very convenient and powerful tool for gold nanoparticle bioconjugation and biomolecular binding studies. The conjugation process between protein A and gold nanoparticles under different experimental conditions and the quality as well as the stability of the prepared conjugates were monitored and characterized systematically by DLS. Furthermore, the specific interactions between protein A-conjugated gold nanoparticles and a target protein, human IgG, can be detected and monitored in situ by measuring the average particle size change of the assay solution. For the first time, we demonstrate that DLS is able to directly and quantitatively measure the binding stoichiometry between a protein-conjugated GNP probe and a target analyte protein in solution.
动态光散射（DLS）是一种分析工具，常用于测量液体环境中纳米粒子和胶体的流体力学尺寸。金纳米粒子（GNPs）在其表面等离子体共振波长处或附近是非常好的光散射体。在这项研究中，我们证明 DLS 可用于金纳米粒子生物缀合和生物分子结合研究的非常方便和强大的工具。通过 DLS 系统地监测和表征不同实验条件下蛋白质 A 与金纳米粒子之间的缀合过程以及制备的缀合物的质量和稳定性。此外，通过测量测定溶液中平均颗粒尺寸的变化，可以原位检测和监测蛋白质 A 缀合的金纳米粒子与靶蛋白（人 IgG）之间的特异性相互作用。我们首次证明，DLS 能够直接定量测量溶液中蛋白质缀合的 GNP 探针与靶分析物蛋白之间的结合计量比。
