IBMM, Univ. Montpellier, CNRS, ENSCM, Montpellier, France.
Department of Chemistry, Vanderbilt University , Nashville, Tennessee 37235, United States.
Anal Chem. 2017 Jun 20;89(12):6710-6718. doi: 10.1021/acs.analchem.7b00946. Epub 2017 Jun 7.
Taylor dispersion analysis (TDA) allows the determination of the molecular diffusion coefficient (D) or the hydrodynamic radius (R) of a solute from the peak broadening of a plug of solute in a laminar Poiseuille flow. The main limitation plaguing the broader applicability of TDA is the lack of a sensitive detection modality. UV absorption is typically used with TDA but is only suitable for UV-absorbing or derivatized compounds. In this work, we present a development of the TDA method for non-UV absorbing compounds by using a universal detector based on refractive index (RI) sensing with backscattering interferometry (BSI). BSI was interfaced to a capillary electrophoresis-UV instrument using a polyimide coated fused silica capillary and an in-house designed flow-cell assembly. Polysaccharides were selected to demonstrate the application of TDA-BSI for size characterization. Under the conditions of validity of TDA, D and R average values and the entire R distributions were obtained from the (poly)saccharide taylorgrams, including non-UV absorbing polymers.
泰勒分散分析（TDA）允许从层流泊肃叶流动中溶质的塞子的峰展宽来确定溶质的分子扩散系数（D）或流体力学半径（R）。困扰 TDA 更广泛应用的主要限制是缺乏敏感的检测模式。TDA 通常使用紫外吸收，但只适用于紫外吸收或衍生化合物。在这项工作中，我们通过使用基于背向散射干涉（BSI）的折射率（RI）感应的通用检测器，为非紫外吸收化合物开发了 TDA 方法。BSI 通过聚酰亚胺涂覆的熔融石英毛细管和内部设计的流量池组件与毛细管电泳-紫外仪器接口。选择多糖来演示 TDA-BSI 用于尺寸表征的应用。在 TDA 的有效性条件下，从（多糖）泰勒图中获得了 D 和 R 平均值以及整个 R 分布，包括非紫外吸收聚合物。
