Gel Electromicrofluidics Assisted In Situ Single Cell Analysis

Analyzing single cells under a microscope is a powerful tool in healthcare, medicine, and homeland security. Typically, biological samples are spread onto glass slides for microscopic examination to detect pathogens or identify biowarfare agents. Current single-cell imaging systems use high-resolution microscopy, which captures only a small sample volume, resulting in limited sensitivity. This project will develop a gel electromicrofluidics (GEM) platform that enhances single-cell imaging by amplifying small, hard-to-detect cells into large, bright fluorescent spots. The technology will improve both sensitivity and throughput, enabling rapid and accurate disease diagnostics. The research will be integrated across several educational fronts, including student-designed projects, graduate program development, undergraduate research opportunities, and outreach programs. This research will establish a GEM-assisted platform, which incorporates sensing gel, electromicrofluidics, and electrokinetic manipulations, for rapid, sensitive, in situ single-cell analysis. The sensing gel will be engineered to amplify small, difficult-to-detect target cells into large, highly fluorescent DNA colonies, allowing visualization of single-cell signals using low-resolution microscopy. This will greatly enhance both sampling efficiency and detection sensitivity. Electromicrofluidics will be used to spread the gel evenly across smear samples via electrowetting, which will eliminate air trapping, a common issue in manual gel spreading, and ensure efficient cell recovery. Additionally, electro-aligned gel and electro-confined polymerase chain reaction (PCR), which leverage electric polarization and dipole-dipole interactions to align gel polymers and DNA molecules, will be studied to advance the mechanistic understanding of the electrokinetic processes involved in gel polymerization and PCR amplification. These electrokinetic manipulations will concentrate DNA and increase fluorescence intensity, thereby enhancing single-cell signals. Furthermore, the GEM platform will be adapted to assess the viability of individual cells following drug treatment, facilitating rapid drug susceptibility testing (DST). Successful completion of this project will lay the groundwork for the next generation of microscopy-based single-cell analysis, with broad applications in disease diagnostics and drug resistance detection. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.