Surface Engineering for Reversible Immunoaffinity Cell Isolation
Funded by the National Science Foundation (PI: Gilchrist)
This research project uses convective deposition to create sacrificial layers of different roughness for controllable cell isolation and release from sophisticated biological fluids. Specific cell isolation with high efficiency has implications in cell based diagnosis. The release mechanism is generic and is expected to yield pure cells in a gentle, non-invasive fashion compatible with conventional cell culture and cell analysis methods. The figures to the right shows surfaces prepared by depositing nanobeads of different sizes on the substrate to control cell-substrate interactions.
Reference: Bu Wang, Pisist Kumnorkaew, Alex Weldon, James F. Gilchrist and Xuanhong Cheng, “Effect of Surface Nano-topography on Immunoaffinity-Based Cell Capture in Microfluidic Devices,” Langmuir, 2011, 27, (17), 11229-11237.
Microfluidics for Bionanoparticle Analysis
Funded by the National Institute of Health and Pennsylvania Department of Health (PI: Cheng)
This research project intends to create various platforms capable of quantifying bionanoparticles, such as virions, in biological fluid. We combine novel nanomaterials with optical, mechanical and electrical sensors to purify, enrich and count target particles in an automated and self-calibrated fashion. Such systems are useful in clinical diagnosis of viral infection, detection of pathogens in the environment and fundamental studies of bionoanoparticle trafficking. The photo to the left shows an optical setup for nanoparticle counting in suspension.
Reference: Chao Zhao, Xuanhong Cheng, “Microfluidic Separation of Viruses from Blood Cells Based on Intrinsic Transport Processes,” Biomicrofluidics,5(3): 032004.
Nanostructured materials for bionanoparticle processing
This project intends to rationally design ordered nanostructure arrays of hierarchical features, on the scale of biomolecules and natural nano-vesicles respectively, for processing complex biological fluidics. The figure to the left shows nanoporous membranes of controlled pore sizes and ordered pore arrangements formed by template guided aluminum anodization.
Reference:Weldon, A. L.; Kumnorkaew, P.; Wang, B.; Cheng, X.; Gilchrist, J. F., Fabrication of Macroporous Polymeric Membranes through Binary Convective Deposition. ACS Applied Materials and Interfaces 2012, 4, (9), 4532-4540.
Real-time, in situ Sensing of Stem Cell Function
Funded by the National Science Foundation (PI: Bartoli)
The goal of this research project is to create biosensors for in situ and real time detection of stem cell function. Such biosensors are important for understanding the fate of stem differentiation and screening cancer therapeutics. The figure to the left shows an Mach-Zehnder Interferometer based on nanoslits for label-free biomolecule sensing. Ongoing efforts include combining the sensor with cell culture microfluidics to directly interrogate cells and provide feedback control.
Reference: Gao, Y.; Gan, Q.; Xin, Z.; Cheng, X.; Bartoli, F. J., Plasmonic Mach–Zehnder Interferometer for Ultrasensitive On-Chip Biosensing. ACS Nano 2011, 5, (12), 9836–9844.