Elnaz Nazemi

Monitoring biological activities of cells and their reactions to specific environments plays an important role in drug development and discovering new methods for curing diseases affecting living organisms. While flow cytometry is a standard method in the study of suspended eukaryotic cells of animals and plants, the analysis of individual cell and cell-cell interaction ex vivo requires the cells to be immobilized on solid substrates and kept in physiological fluid environments. At the present time most studies tend to be focused on multiple cells, however, the need for analyzing cells at a single-cell level is more in demand in the biological research community.

The project “Photonic biosensing for monitoring biological activities of bacteria and selected eukaryotic cells immobilized on biofunctionalized surfaces of quantum semiconductors” represents a new direction of research in the QS-PBNT Laboratory aimed at monitoring biological activity of live bacteria and selected eukaryotic cells immobilized on biofunctionalized surfaces of QS microstructures. The idea is to collect photoluminescence (PL) maps of QS microstructures interfaced with live biological cells for studying the reaction of cells exposed to different environments. From the information about spatially resolved PL intensity signal, one could deduce the distribution of electric charge on the cell surface. Electrical potentials associated with cell membranes are involved in a large number of cellular processes, thus, being able to measure such potentials makes it possible to study these processes and the functioning of cells in different environments. Photonic measurements of electric charge induced effects in biological cells have the advantage of “non-contact” rapid diagnostics. Our approach is to take advantage of this property and demonstrate monitoring of some cellular functions that until now were either impossible to observe, or required the application of complicated (expensive) tools. The results of this project have the potential to lead to significant progress in biological cell study, advancement of methods for therapeutic cell treatment and drug discovery.