title: Nanohole Array-Directed Trapping of Mammalian Mitochondria Enabling Single Organelle Analysis.
abstract: We present periodic nanohole arrays fabricated in free-standing metal-coated nitride films as a platform for trapping and analyzing single organelles. When a microliter-scale droplet containing mitochondria is dispensed above the nanohole array, the combination of evaporation and capillary flow directs individual mitochondria to the nanoholes. Mammalian mitochondria arrays were rapidly formed on chip using this technique without any surface modification steps, microfluidic interconnects, or external power sources. The trapped mitochondria were depolarized on chip using an ionophore with results showing that the organelle viability and behavior were preserved during the on-chip assembly process. Fluorescence signal related to mitochondrial membrane potential was obtained from single mitochondria trapped in individual nanoholes revealing statistical differences between the behavior of polarized vs depolarized mammalian mitochondria. This technique provides a fast and stable route for droplet-based directed localization of organelles-on-a-chip with minimal limitations and complexity, as well as promotes integration with other optical or electrochemical detection techniques.
authors.affiliation: Department of Electrical and Computer Engineering, ‡Department of Biomedical Engineering, and §Department of Chemistry, University of Minnesota , Minneapolis, Minnesota 55455, United States.
authors.forename: Shailabh
authors.initials: S
authors.lastname: Kumar
authors.affiliation: Department of Electrical and Computer Engineering, ‡Department of Biomedical Engineering, and §Department of Chemistry, University of Minnesota , Minneapolis, Minnesota 55455, United States.
authors.forename: Gregory G
authors.initials: GG
authors.lastname: Wolken
authors.affiliation: Department of Electrical and Computer Engineering, ‡Department of Biomedical Engineering, and §Department of Chemistry, University of Minnesota , Minneapolis, Minnesota 55455, United States.
authors.forename: Nathan J
authors.initials: NJ
authors.lastname: Wittenberg
authors.affiliation: Department of Electrical and Computer Engineering, ‡Department of Biomedical Engineering, and §Department of Chemistry, University of Minnesota , Minneapolis, Minnesota 55455, United States.
authors.forename: Edgar A
authors.initials: EA
authors.lastname: Arriaga
authors.affiliation: Department of Electrical and Computer Engineering, ‡Department of Biomedical Engineering, and §Department of Chemistry, University of Minnesota , Minneapolis, Minnesota 55455, United States.
authors.forename: Sang-Hyun
authors.initials: SH
authors.lastname: Oh
mesh_terms: D000818:Animals; D003584:Cytological Techniques; D005453:Fluorescence; D006801:Humans; D056656:Lab-On-A-Chip Devices; D008928:Mitochondria / Q000737:chemistry*; D013499:Surface Properties; D014634:Valinomycin / Q000737:chemistry
chemical_list: D014634:Valinomycin