OPTICAL LASER TRAP FOR BIOLOGICAL CELL STUDIES

荧光光谱和激光散射将用于 量化辐射引起的加热和细胞损伤效应， 发生在脂质体和精子细胞的光学显微操作过程中 使用光学镊子。加热和热效应，如果诱发， 产生光化学和光生物学变化， 导致细胞结构和功能的改变。评估…的程度 该光学捕获是非侵入性和非破坏性的过程， 光学激光陷阱将首次与 荧光检测和前向光散射测量系统， 同时进行限制、显微操作和光照， 脂质体试验颗粒和海星的激发/发射研究， 人类精子细胞研究的前提是，作为聚焦激光， 辐射被细胞吸收，其温度升高，并且可以 在脂质体的荧光发射光谱中产生位移， 含温度依赖性膜和核荧光的细胞 probes.用荧光染料标记脂质体试验细胞; 由光镊限制;激发和检测荧光;以及 作为光镊参数的函数进行的测量， 包括功率、波长和曝光时间。偏离正常细胞 结构和功能将被用作细胞加热和损伤的测定 方面的影响.该项目的具体目标包括： 捕获和诊断测量能力;制造和 脂质体作为模型细胞样品和宿主的荧光检测的校准 薄膜探头.光散射轮廓和温度的测量 作为激光捕获函数的依赖荧光发射光谱 参数;激光-细胞相互作用的分析建模;以及， 应用相同的技术来评估加热和电池 海星和人类精子的损伤，使用活力和精子速度， 鞭毛搏动频率，膜荧光，核荧光 DNA和染色质结构，以及生殖能力作为衡量 潜在的伤害。本文描述的技术将为以下操作提供基础： 了解光镊辐射对脂质体和精子的影响 细胞，作为重要运输工具的生物系统 人体内的药物酶和遗传物质。

Fluorescence spectroscopy and laser light scattering will be used to quantify the radiation induced heating and cell damage effects that may occur during the optical micromanipulation of liposomes and sperm cells using optical tweezers. Heating and thermal effects, if induced, may produce photochemical and photobiological changes that can ultimately result in altered cell structure and function. To assess the degree to which optical trapping is a non-invasive and non-destructive process, an optical laser trap is to be integrated, for the first time, with a flourescence detection and forward light scattering measurement system, for the simultaneous confinement, micromanipulation, and light excitation/emission study of liposome test particles, and starfish and human sperm cells. The research premise is that, as focused laser radiation is absorbed by a cell, its temperature increases, and can produce a shift in the fluorescence emission spectrum of liposomes and cells containing temperature-dependent membrane and nuclear fluorescent probes. A liposome test cell is to be tagged with a fluorescent dye; confined by an optical tweezer; fluorescence excited and detected; and measurements made as functions of the optical tweezer parameters, including power, wavelength, and exposure time. Departure from normal cell structure and function will be used as assays for cell heating and damage effects. The specific aims for this project include: integration of the trapping and diagnostic measurement capabilities; fabrication and calibration of liposomes as model cell samples and hosts for fluorescent membrane probes; measurement of light scattering profiles and temperature dependent fluorescence emission spectra as a function of laser trapping parameters; analytical modeling of the laser-cell interaction; and, application of the same techniques to the assessment of heating and cell damage in starfish and human sperm, using motility and sperm velocity, flagellar beat frequency, membrane fluorescence, nuclear fluorescence of DNA and chromatin structure, and reproduction capability as a measure of potential damage. The techniques described herein will provide a basis for understanding optical tweezer radiation effects on liposomes and sperm cells, biological systems that function as important transport vehicles for drugs, enzymes, and genetic material within the human body.