The researchers developed an array of hundreds of sensors on a chip. They can culture cells on the chip similar to the way scientists grow cells in a dish. Thus, they can collect data from many cells at once, while still recording individual cellular measurements.
Another advantage of these microsensors is the ability to image cells with microscopes while cells grow on the sensors. Researchers can track the cells visually, opening the possibilities of tracking various cellular processes in conjunction with changes in mass.
"Imaging acts as a control. You can actually watch the cell divide and grow and correlate that to your measurements. It really validates what you have," Bashir said. "There are lots of optical measurements that now you can integrate with mass sensing."
Through measurements of live and fixed cells, the researchers were also able to extract physical properties such as stiffness through mathematical modeling. Some cell types are stiffer than others; for example, bone cells are more firm, while neurons are more gelatinous. Mechanical science and engineering professors Narayana Aluru and K. Jimmy Hsia, co-authors of the paper, performed extensive analytical and numerical simulation to reveal how cell stiffness and contact area affect mass measurement.
Next, the researchers plan to extend the study to other cell lines, and explore more optical measurements and fluorescent markers.
"These technologies can also be used for diagnostic purposes, or for screening. For example, we could study cell growth and mass and changes in the cell structure based on drugs or chemicals," Bashir said.
|Contact: Liz Ahlberg|
University of Illinois at Urbana-Champaign