IBMM, Université de Montpellier, CNRS, ENSCM , Montpellier 34095, France.
Laboratoire de Physique et Mécanique des Milieux Hétérogènes (PMMH), ESPCI Paris, CNRS, PSL (Paris Sciences et Lettres) Research University, Sorbonne Université, Université Paris-Diderot , 10 rue Vauquelin, 75231 Paris Cedex 05, France.
Anal Chem. 2017 Dec 19;89(24):13487-13493. doi: 10.1021/acs.analchem.7b03806. Epub 2017 Nov 28.
Taylor dispersion analysis (TDA) is an absolute method (no calibration needed) for the determination of the molecular diffusion coefficient (D) based on the band broadening of a solute in a laminar flow. TDA is virtually applicable to any solute with size ranging from angstrom to sub-micrometer. The higher sizing limit is restricted by the occurrence of possibly two regimes: convective and hydrodynamic chromatography (HDC) regimes, which have different physical origins that should not be confused. This work aims at clearly defining the experimental conditions for which these two regimes can play a role, alone or concomitantly. It also calculates the relative error on D due to the HDC regime according to the solute to capillary size ratio. It is demonstrated in this work that HDC does not significantly affect the TDA measurement as long as the hydrodynamic radius of the solute is lower than 0.0051 times the capillary radius. Experimental illustrations of the occurrence of the two regimes are given taking polystyrene nanoparticles as model solutes. Finally, application of TDA to the sizing of large real-life solutes is proposed, taking cubosomes as new drug nanocarriers of potential interest for drug delivery purposes.
泰勒分散分析（TDA）是一种基于层流中溶质的带宽展宽来测定分子扩散系数（D）的绝对方法（无需校准）。TDA 实际上适用于任何尺寸从埃到亚微米的溶质。较高的尺寸限制由可能出现的两种状态的发生所限制：对流和流体力学色谱（HDC）状态，它们具有不同的物理起源，不应混淆。这项工作旨在明确界定这两种状态可能单独或同时起作用的实验条件。它还根据溶质与毛细管尺寸的比例计算了由于 HDC 状态引起的 D 的相对误差。这项工作表明，只要溶质的流体力学半径低于毛细管半径的 0.0051 倍，HDC 就不会显著影响 TDA 的测量。以聚苯乙烯纳米颗粒为模型溶质，给出了两种状态发生的实验说明。最后，提出将 TDA 应用于大型实际溶质的尺寸测定，以立方纳米载体作为药物输送目的有潜在兴趣的新型药物纳米载体。
