Université de Pau et des Pays de l'Adour (UPPA)/CNRS, Laboratoire de Chimie Analytique Bio-Inorganique et Environnement, UMR IPREM 5254, Technopôle Hélioparc, Av. du Président Angot, 64000 PAU, France.
J Chromatogr A. 2010 Dec 10;1217(50):7891-7. doi: 10.1016/j.chroma.2010.10.042. Epub 2010 Oct 15.
Asymmetrical flow field-flow fractionation (AFlFFF) hyphenated to multi-angle laser-light scattering (MALS) was evaluated in order to determine single walled carbon nanotube (SWCNT) length distribution. Fractionation conditions were investigated by examining mobile phase ionic strength and pH, channel components and cross-flow rate. Ammonium nitrate-based mobile phase with 10(-5)molL(-1) ionic strength and pH 6 allows the highest sample recovery (89±3%) to be obtained and the lowest loss of the longest SWCNT. A cross-flow rate of 0.9mLmin(-1) leads to avoid any significant membrane-sample interaction. Length was evaluated from gyration radius measured by MALS by comparing SWCNT to prolate ellipsoid. In order to validate the fractionation and the length determination obtained by AFlFFF-MALS, different SWCNT aliquots were collected after fractionation and measured by dynamic light scattering (DLS). AFlFFF is confirmed to operate in normal mode over 100-2000nm length. MALS length determination after fractionation is found to be accurate with 5% RSD. Additionally, a shape analysis was performed by combining gyration and hydrodynamic radii.
为了测定单壁碳纳米管（SWCNT）的长度分布，评估了不对称流场流分离（AFlFFF）与多角度激光光散射（MALS）联用。通过考察流动相离子强度和 pH 值、通道组件和交叉流速来研究分馏条件。基于硝酸铵的流动相，离子强度为 10(-5)molL(-1)，pH 值为 6，可获得最高的样品回收率（89±3%），并使最长的 SWCNT 损失最小。交叉流速为 0.9mLmin(-1)，可避免任何显著的膜-样品相互作用。通过将 SWCNT 与扁长椭球比较，由 MALS 测量的回转半径评估长度。为了验证 AFlFFF-MALS 得到的分馏和长度测定，在分馏后收集不同的 SWCNT 等分试样并通过动态光散射（DLS）进行测量。证实 AFlFFF 在 100-2000nm 长度范围内以正常模式运行。分馏后的 MALS 长度测定结果准确，相对标准偏差为 5%。此外，还通过结合回转半径和流体力学半径进行了形状分析。
