Flow Instrument for Two-color Assay on Microtransponders

DESCRIPTION (provided by applicant): PharmaSeq provides ultra-small micro transponders and a fluidics-based, bench-top flow reader as tools to perform complex bioassays. A micro transponder is an integrated circuit with an electronically stored ID (64 bits) and the capability to transmit the ID by radio frequency. Each chip is composed of photocells, electronic memory and antenna. In its memory, the chip stores information that identifies the sequence of the genetic material attached to the chip. The transmission of information occurs upon illumination by laser light, which powers the chip. PharmaSeq developed two versions of micro transponders, namely 500x500 and 250x250 microns in size. The assay involves three phases: conjugation or synthesis of probe molecules on the micro transponder surface, reaction with target molecules labeled with a fluorescent dye, and readout of the micro transponders by a flow reader. The flow reader has two functions: to read each micro transponder's ID and to measure fluorescence from the reporter molecules bound on the micro transponder's surface. The fluidics system directs micro transponders one-by-one to the flow chamber, where the chips are illuminated by light, the micro transponder ID read, and fluorescence measured. The main goal of the present project is to build a two-color instrument for reading micro transponders to permit quantitative bioassays. The instrument will be capable of simultaneously reading fluorescence from micro transponders at two wavelengths, 570 nm (Cy3 dye) and 670 nm (Cy5 dye). The project will involve significant changes to the existing instrument, in particular, addition of a automated sample loader, redesign of the optical system, as well as a rewrite of the instrument and data analysis software. The major benefit is to provide a reference and to provide accurate comparison between two samples. The instrument will enable, in particular, a two-color expression profiling experiments as well as many other types of assays currently done on micro arrays or flow hyetometers. The flow reader can be used for diagnostics in vitro and drug discovery projects.