PharmaSeq has developed proprietary technologies for performing nucleic acid-based assays using unique light-powered microtransponders. It is a privately held early-stage biotechnology company with research and development facilities located in Monmouth Junction, NJ, near Princeton. The company has nine patents from the U.S. Patent and Trademark Office covering microtransponder-based assays. PharmaSeq's strategy is to apply microtransponder technology initially to DNA and protein diagnostic assays, and then move forward in genomics, forensics, pharmaceutical drug discovery, communications and other areas.

Methods for the detection of nucleic acids and proteins will be among the most rapidly growing techniques used in medical diagnostics laboratories in the early twenty-first century. While our understanding of the underlying genetic and biochemical mechanisms has rapidly grown due to the progress of the human genome program, our ability to rapidly and inexpensively determine relevant DNA sequence information for any given individual is lacking.

Microtransponders like the one shown in the figure to the right are used in a novel DNA detection system to quickly and accurately detect and differentiate large numbers of unique DNA sequences in a single assay. Each microtransponder is an integrated circuit composed of photocells, memory, clock and antenna. The microtransponder stores information identifying the sequence of an attached oligonucleotide probe in its electronic memory. Microtransponders coated with DNA probes are stable for long periods of time, making them ideal for use in medical research and commercial assays. Complementary DNA sequences in a biological specimen bind to DNA probes on microtransponders using proprietary chemistry. Similarly, antibodies can be used to detect protein antigens.

A scanner then detects two signals: 1) the fluorescent signal generated by the labeled specimen nucleic acid hybridized to the probe on the microtransponder, and; 2) the unique identification number of the microtransponder. The scanner shown is a high-speed flow fluorometer modified to detect radio frequency. When many probes (and thus, many microtransponders) are used in an assay, the scanner very rapidly identifies which microtransponder(s) are involved in the reaction by activating the transponder's memory by laser. Thus, positive DNA probe hybridizations are identified. This multiplex feature makes the technology ideal for assays in which screening for several genes, gene fragments or mutations is necessary, which are vital requirements in medicine and research. It also allows specimens to be screened for multiple pathogens quickly and accurately. Protein detection assays have also been performed successfully using assay designs such as the one shown below.

Multiplex DNA assays often employ two-dimensional (2D) arrays of DNA molecules on glass surfaces. PharmaSeq's novel microtransponder-based assay offers the advantage of three-dimensional (3D) arrays of DNA probes. The probes are indexed by the unique serial number of the DNA probe encoded in the memory of the microtransponder. This liquid 3D array is disassembled for the fluorescence measurements and analyzed as a linear string of solid-phase particles speeding through the flow chamber of the scanner. PharmaSeq's assay will have superior sensitivity, selectivity and high throughput, and will be upgradeable with new DNA probes. Alternatively, it allows the use of relatively few probes at low cost in an assay that does not require a high multiplex level or expensive and unique equipment. The DNA probe assays are configured in the same manner as current diagnostic assays for ease of use.

Copyright © 2012 PharmaSeq, Inc.