University at Buffalo - The State University of New York

Published: July 27, 2006

By KARIN ABU-MIDDAIN
Reporter Contributor

UB researchers have developed a microfluidic device that rapidly tests live cells for responses to any stimulus by using electrical resistance to measure changes in cell volume. The device can measure the volume of organelles, vesicles and any other insulating objects, such as the latex beads used in various biochemical assays. The chip has numerous potential applications, including the detection of drug/cell interactions, bacterial sensitivity to antibiotics and cancer-cell susceptibility to chemotherapeutic agents.

The project is funded by a $750,000 Technology Transfer Incentive Program (TTIP) grant from the New York State Office of Science, Technology and Academic Research (NYSTAR), and matching funds from Reichert Inc. of Depew, which is licensing the technology. Reichert, a leader in ophthalmic instruments, laboratory refractometers and microscope services, sees this technology as a major opportunity in its growing business serving the emerging bioresearch market.

"The TTIP program is designed to partner universities with New York State companies in commercializing leading-edge technologies, and provides critical resources to develop technologies so that they are ready for licensing," said Robert J. Genco, vice provost and director of the UB Office of Science, Technology Transfer and Economic Outreach (STOR). STOR worked with the researchers and Reichert to submit the grant application and license the technology.

Frederick Sachs, professor in the Department of Physiology and Biophysics, School of Medicine and Biomedical Sciences, and Susan Z. Hua, assistant professor in the Department of Mechanical and Aerospace Engineering, School of Engineering and Applied Sciences, are the primary inventors of the technology.

Cell volume is a universal measure of cell metabolism. However, it has not been used for cell-based screening because conventional methods to measure cell volume, such as microscopy, are complex and time-consuming. The UB invention can measure the volume of a small number of cells in real-time with unprecedented resolution.

"Cells are electrical insulators," said Hua. "When they are immersed in electrically conductive salt water within the sensor, the cells displace some of the water and reduce the current. If the cells swell, as might happen in the presence of a toxin, the sensor resistance increases, providing a quantitative measure of the cellular response."

The prototype device is a microfabricated chip made of silicon, glass and platinum that is inexpensive and reusable.

"The combination of New York State support, the easy collaboration with UB and Reichert's ability to serve the market with a product makes for very strong growth potential," said Robert Carey, general manager of analytical instruments at Reichert. Cell-volume measurement is complementary to Reichert's Surface Plasmon Resonance (SPR) instruments that provide real-time measurement of molecular interaction.

The invention has applications in both the diagnostic and research markets. In the health-care industry, for example, current methods for testing bacterial resistance to antibiotics are labor-intensive and costly. Moreover, these methods often require 24 to 48 hours, during which time physicians prescribe a "best-guess" treatment for their patients. With its ability to detect antibiotic sensitivity within 15 minutes, the microfluidic sensor has the potential to save lives and reduce health care costs.

In the research markets, pharmaceutical companies need methods to screen drug candidates rapidly. A fast, small-volume, high-throughput detector for drug-cell interactions would save companies time and money.