RII Track-4:NSF: In-vitro Cytotoxicity Assessment of Synthesized Quantum Dots for Enhanced Cell Imaging

Quantum dots (QDs) are nano-sized particles, typically ranging from 2-10 nm, that are widely used as fluorescent cell-labeling tools. Some Cadmium-containing QDs have demonstrated effective cell imaging quality and high binding efficiency, but their toxicity poses risks to the life and function of the cells. Identifying an optimal QD candidate with minimum hazards to the cells is crucial for the detection and tracking of a variety of living organisms. This proposed research will implement micro-scale fluid channels to fabricate Cadmium-free QDs that are less toxic to cells but maintain high imaging quality. The study will quantitatively assess the impact of these customized QDs on the photosynthesis rate and viability of microalgae cells. Results from this work will strengthen the current understanding of the interaction between QDs and microalgae cells and provide insight into the QDs as a cell-labeling tool for other biological systems. This fellowship program will train the PI and a graduate student from Louisiana Tech University in both the fundamental knowledge of cell biology and experimental technical skills such as the mass spectrometry process. This collaborative work will enhance the research capacity of Louisiana Tech University and facilitate training and education in Northern Louisiana. This Research Infrastructure Improvement Track-4 EPSCoR Research Fellows (RII Track-4) project will provide a fellowship to an Assistant Professor and a graduate student at Louisiana Tech University. This work will be conducted at the University of California, Riverside. Quantum dots (QDs), such as CdSe/ZnS, have been shown a detrimental impact on the cells despite their effectiveness as cell-labeling tools. Knowing the toxicity of CdSe/ZnS on cells, the objective of this project is to develop QDs with low toxicity while maintaining the same quality of imaging and binding effect with cells. The PI will implement microfluidics devices for QDs synthesis and fabrication, and develop microfluidic channels for in vitro cytotoxicity assessment with specific cells. With the support from the collaborator, the PI will synthesize and characterize the QDs using the full capability of nanomaterial characterization and microfluidic control setup. In addition, this collaborative work also allows the PI and graduate student to have access to the cell culture facility and perform single-cell analysis at the host site for microalgae cell photosynthesis rate tests. This project will achieve the following aims: 1) synthesize low-toxic QDs using droplet-based microfluidic devices and characterize the imaging quality of QDs, and 2) evaluate the cytotoxicity of QDs to the microalgae cells with external flow using a microfluidic device. The results from this research hold the potential to advance further research towards other living organisms that are crucial to the marine system or environmental protection. 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.