Anal Chem. 2012 Aug 7;84(15):6308-11. doi: 10.1021/ac301149k. Epub 2012 Jul 10.
Although electrospray-differential mobility analyzers (ES-DMA) have been previously employed to characterize ligand binding to nanoparticles, absolute quantification of surface coverage can be inaccurate at times because of ligand conformational effects. In this Letter, we report a quantitative technique by in-flight coupling of a particle mass analyzer (APM) with ES-DMA, thus enabling a direct quantitative analysis of mass independent of particle size, material, morphology and conformation. We demonstrate the utility of ES-DMA-APM by studying two model complex systems (gold nanoparticle-bovine serum albumin and polystyrene bead-antibody) as a function of concentration and pH. Our results obtained with ES-DMA-APM are in excellent agreement with prior work. We anticipate that this will enhance the capabilities of online quantitative characterization of ligand binding to nanoparticles.
尽管电喷雾-差分迁移率分析仪 (ES-DMA) 已被用于表征配体与纳米颗粒的结合，但由于配体构象效应，表面覆盖率的绝对定量有时可能不准确。在本信函中，我们报告了一种通过飞行中颗粒质量分析仪 (APM) 与 ES-DMA 耦合的定量技术，从而能够直接对质量进行定量分析，而与颗粒尺寸、材料、形态和构象无关。我们通过研究两个模型复杂体系（金纳米颗粒-牛血清白蛋白和聚苯乙烯珠-抗体）作为浓度和 pH 的函数，展示了 ES-DMA-APM 的实用性。我们用 ES-DMA-APM 获得的结果与先前的工作非常吻合。我们预计这将增强在线定量表征配体与纳米颗粒结合的能力。
