This project aims to develop a platform for simultaneous and parallel micromanipulation of thousands of particles including both living cells and microspheres. The technology should offer a powerful tool for moving, trapping, assembling, positioning, examining, and sorting single particles and cells. Such capabilities have a broad range of potential applications in the fields of diagnostics, drug discovery, therapeutics, and basic research. An imaging fiber bundle will be coupled to a laser and the laser beam will be divided into an array of thousands of small focused spots, forming an array of optical traps. Initial work will focus on improving the system's capabilities to array particles to enable dense arrays of up to 1000 traps to be created. A microfluidics platform will be integrated into the system to enable solutions to be delivered to the array in a reproducible manner. The optical tweezers will optically trap single cells and microparticles of various sizes, ranging from 1 micron to tens of microns. In addition, the system will be integrated with a device for controlling each individual optical trap in the array, thereby enabling the system to selectively trap and release individual particles or cells. After system improvements have been performed to enhance the existing capabilities of the instrument, several proof-of-concept experiments will be performed to determine the system's capabilities and limitations. Such applications include DNA arrays and cell trapping. The long-term goal of the proposed work is to develop a platform technology for performing screening and selecting many particles or cells simultaneously. The technology has applicability to cell selection, blood and tumor diagnosis, combinatorial screening, nanoassembly, gene expression analysis and a wide variety of screening, selection, and diagnostic applications.