Fabrication of cell recognition device by the luminescent nanocrystalline silicon and development of the biomedical measurement system

发光半导体纳米粒子如硫化镉（cd）和硒化镉（CdSe）在生物医学工程领域的应用得到了广泛的研究。然而，这些纳米颗粒材料在生物安全性、生产成本、资源、环境影响和粒径等方面存在一些问题。因此，有望开发出具有无害、价格适中、资源丰富、对环境影响小、粒径小等特点的新型纳米颗粒材料。通过控制纳米晶硅的粒径，制备出了从红光到蓝光连续发光的纳米晶硅（nc-Si）颗粒。本文研究了纳米硅颗粒在动物静脉中的发光特性和流动情况。采用硅片/硅靶共溅射和高温后退火的方法，在Si衬底上形成了粒径为2.5 nm的纳米硅颗粒，并包埋在氧化层中。然后，在氢氟酸蒸汽中蚀刻围绕nc-Si颗粒的氧化层，以有效地将许多颗粒提取到衬底表面。蚀刻处理后，样品在纯水中冲洗，因为吸附在nc-Si颗粒表面的HF酸颗粒对生物体具有很高的毒性。漂洗后的纳米硅颗粒通过超声振动处理从基质上摇落到生理盐水溶液中。然后将含有nc-Si颗粒的NSS注射到大鼠、羔羊等动物的静脉中。利用光子多通道分析仪可以很容易地检测到纳米硅颗粒在静脉中的发光特性。采用313 nm的带通滤光片，氙灯为光源。当纳米硅颗粒以1.3 mg的颗粒浓度注入静脉时，纳米硅颗粒稳定、平稳地流入通道。此外，在纳米硅颗粒在静脉中流动的条件下，它们表现出强烈的红色发光，在720 nm处有一个峰值。在生物体内的冠状动脉和小肠壁等不同部位也证实了良好的流动和红色发光。这些现象的产生是由于形成了粒径为2.5 nm的小颗粒，并在颗粒表面形成了稳定的钝化膜。少

Luminescent semiconductor nanoparticles such as cadmium sulfide (CdS) and cadmium selenide (CdSe) have been widely studied for application to biomedical engineering fields. These nanoparticle materials, however, have some problems for safety to living organism, production cost, resource, environmental influence and particle size. Therefore, it is expected to develop the new nanoparticle materials with some features of unharmfulness, moderate price, resourcefulness, low environmental influence and minimal particle size. We have been fabricated the nanocrystalline silicon (nc-Si) particles, which continuously emits from red light up to blue light by controlling the particle size.In this study, the luminescent property and flow condition of nc-Si particles in the vein of animal have been investigated. The nc-Si particles with a size of 2.5 nm embedding in an oxidized layer were formed on a Si substrate by co-sputtering of Si chips/silica targets and post-annealing at high temperature. The … More oxidized layer surrounding nc-Si particles, then, was etched in hydrofluoric (HF) acid steam to effectively extract the many particles onto the substrate surface. After etching treatment, the sample was rinsed in the pure water, because the HF acid particle adsorbed on the surface of nc-Si particle have the high toxicity for the living organism. The nc-Si particles after rinse treatment were shaken off from the substrate into the normal saline solution (NSS) by supersonic vibration treatment. After that, the NSS containing the nc-Si particles was injected into the vein of animal such as rat and lamb. The luminescent property of nc-Si particles in the vein was easily detected by using a photonic multichannel analyzer. A Xenon lamp was used as the light source with an optical bandpass filter of 313 nm. When the nc-Si particles were injected at the particle concentration of 1.3 mg in the vein, they stably and smoothly flowed into their channels. Moreover, they exhibited strong red luminescence with a peak at 720 nm under the flow condition of nc-Si particles in the vein. The good flow and red luminescence was also confirmed for the various positions such as a coronary artery and wall of the small intestine in the living organism. These phenomenon were achieved by the formation of particle with the small size of 2.5 nm and existence of stable passivation film on the particle surface. Less