Highly sensitive determination in a microscopic region using a near-field microscope.

(1)目的为了提高一种高灵敏度、高效率的显微分析技术，需要建立一种基于近场共聚焦激光诱导荧光显微镜的新仪器。(2)结果(1)设计与建造。/购买了一台二维CCD系统，使用一台氩激光器和一台半导体激光器作为激发源，以提高灵敏度和空间分辨率。(2)光纤束系统。/新仪器的一个独特之处在于使用了光纤束。该束在显微镜焦点处是圆形的，以获得宽区域的图像，并且在单色仪的狭缝处是线性的。这种配置允许在CCD上同时观察每根光纤上的荧光。(3)图像呈现。/CCD上的图像允许直接观察水面上的分子动力学。(4)卟啉的荧光光谱。/测量了几种卟啉在水面上的荧光光谱，发现它们与碳氢化合物中的荧光光谱一致。因此，我们可以得出结论，水表面和碳氢化合物一样疏水。(5)水表面动力学。/时间分辨荧光光谱表现出一定的波动，可以用分子在水面上形成团簇，团簇在水面上运动的模型来解释。(6)花菁类化合物的荧光光谱。/几种花菁类化合物的荧光光谱在水面上测量，与碳氢化合物中的荧光光谱一致。因此，水面的疏水性与碳氢化合物的体积一样大。(7)结论。/由于布朗运动造成长期积累的困难，敏感性并不像预期的那么高。

(1) PurposeIn order to improve a highly sensitive and effective analytical technique in a microscopic region, a new instrument should be constructed based on near-filed and confocal laser-induced fluorescence microscopy. Various application should also be carried out.(2) Results(1) Desigh and construction.///A new laser-induced fluorescence microscope instrument was design and constructed with a purchase of a two-dimensional CCD system using an Argon laser and a diode laser as excitation sources to improve sensitivity and spatial resolution.(2) Optical fiber bundle system.///A unique feature of the new instrument lies in the use of optical fiber bundle. The bundle was circular at the microscope focus to obtain images of a wide region and linear at the slit of the monochromator. This configuration allowed to observe fluorescence at each optical fiber simultaneously on CCD.(3) Image presentation.///The image on CCD allowed direct observation of molecular dynamics on water surface. The molecules stayd on water surface like an island.(4) Fluorescence spectrum of porphyn.///The fluorescence spectra of several porphyns were measured on water surface and found to agree with those in hydrocarbons. Thus, we can conclude that the water surface is as hydrophobic as the bulk of hydrocarbons.(5) Dynamics on water surface.///The time-resolved fluorescence spectra showed some fluctuation, which can be understood by a model that molecules form a cluster on water surface and clusters are moving on it.(6) Fluorescence spectrum of cyanines.///The fluorescence spectra of several cyanines were measured on water surface and agreed with those in hydrocarbons. Thus, the water surface is as hydrophobic as the bulk of hydrocarbons.(7) Conclusion.///The sensitivity has been not as much high as expected due to difficulties in long-time accumulation owing to the Brownian motion.