Department of Applied Chemistry, School of Engineering, The University of Tokyo, Bunkyo, Tokyo, Japan.
J Sep Sci. 2011 Oct;34(20):2920-4. doi: 10.1002/jssc.201100501. Epub 2011 Aug 9.
An ultrasensitive absorbance detector, the differential interference contrast thermal lens microscope (DIC-TLM), was employed for a chromatography system using silica nanochannel. Recently, separation of ultrasmall volume sample has been strongly required for single-cell biological and chemical analysis. Previously, we have developed a chromatography system using nanochannels of ~100 nm scale (extended nanochannels) fabricated on a silica substrate. The extended nanochromatography realized highly efficient separation of samples <1 fL without packing materials. However, its detection method was limited to fluorescence method due to the small volume, and a new detector based on absorbance has been required. On the contrary, we have also developed DIC-TLM, a photothermal spectrometer based on absorption and thermal relaxation of sample for determination of concentration of nonfluorescent molecules in extended nanochannel. In this paper, we combined the extended nanochromatography and the DIC-TLM for separation and detection of nonfluorescent dyes. Particularly, basic performances of the DIC-TLM including quantitative performance and sensitivity were deliberated for injected samples of ~fL volume.
一种超灵敏吸光度检测器，差分干涉对比热透镜显微镜（DIC-TLM），被用于一种使用硅胶纳米通道的色谱系统。最近，单细胞生物和化学分析对超小体积样品的分离提出了强烈的要求。之前，我们已经开发了一种使用 ~100nm 尺度纳米通道（扩展纳米通道）的色谱系统，该通道是在硅胶基底上制造的。扩展纳米色谱实现了对无填料的 <1fL 样品的高效分离。然而，由于体积小，其检测方法仅限于荧光法，因此需要一种基于吸光度的新型检测器。相反，我们还开发了 DIC-TLM，这是一种基于样品吸收和热弛豫的光热分光光度计，用于测定扩展纳米通道中非荧光分子的浓度。在本文中，我们将扩展纳米色谱和 DIC-TLM 结合起来，用于分离和检测非荧光染料。特别是，对注入的 ~fL 体积的样品进行了 DIC-TLM 的定量性能和灵敏度等基本性能的讨论。
