Single-Microparticle Measurements: Laser Trapping-Absorption Microspectroscopy under Solution-Flow Conditions.
Single-Microparticle Measurements: Laser Trapping-Absorption Microspectroscopy under Solution-Flow Conditions.
复制标题
单微粒测量：溶液流动条件下的激光捕获吸收显微光谱。
DOI：
10.1021/ac990450d
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发表时间：
1999
影响因子：
7.4
通讯作者：
N. Kitamura
中科院分区：
文献类型：
--
作者：
H. B. Kim;O Kogi;N. Kitamura
研制了一套结合流体歧管的激光捕获-显微光谱分析系统，用于操纵和分析“单个”微粒。将含有微粒的样品溶液引入显微镜工作台上的流动池中，单个微粒被1064 nm的激光捕获。随着颗粒被捕获，其他颗粒被流动的水抽出，将独特的微粒保持在流动池中。在溶液流动条件下，单个微粒受到梯度(F(G))和斯托克斯力(F(S))的平衡捕获，从而使捕获位置向1064 nm激光焦点的下游移动。根据F(G)和F(S)讨论了颗粒这种特殊位置位移的流速和颗粒大小的依赖关系。在这些研究的基础上，优化了进行激光捕获颗粒吸收显微光谱的光学要求，并应用该技术研究了染料在单个微粒中的吸附过程的时间过程。首次测定了罗丹明B对单个微粒的吸附速率。
A laser trapping-microspectroscopy system combined with a fluid manifold was developed to manipulate and analyze "single" microparticles. A sample solution containing microparticles was introduced to a flow cell set on a microscope stage, and a single particle was trapped by a 1064-nm laser beam. With the particle being trapped, the other particles were pumped out by flowing water to hold the unique microparticle in the flow cell. Under solution-flow conditions, a single microparticle was laser trapped in balance with the gradient (F(g)) and Stokes forces (F(s)) experienced by the particle, and thus, the trapped position was shifted to the downstream side of the 1064-nm laser beam focus. Flow rate and particle size dependencies of this particular positional displacement of the particle were discussed in terms of F(g) and F(s). On the basis of these studies, optical requirements to conduct absorption microspectroscopy of a laser-trapped particle were optimized, and the technique was applied to study a time course of dye adsorption processes in single microparticles. The adsorption rate of Rhodamine B was determined for individual microparticles for the first time.