title: Total internal reflection microscopy for live imaging of cellular uptake of sub-micron non-fluorescent particles.
abstract: This paper presents a simple, high-resolution, non-fluorescent imaging technique called total internal reflection microscopy (TIRM) and demonstrates its potential application to real-time imaging of live cellular events. In addition, a novel instrument is introduced that combines the simplicity of TIRM with the specificity afforded by dual-colour total internal reflection fluorescence (TIRF) microscopy and allows sequential imaging with the two modalities. The key design considerations necessary to apply these imaging modes in a single instrument are discussed. The application of TIRM alone yielded high-resolution live images of cell adherence to a poly-L-lysine modified substrate, whereby fine cellular structures are imaged. Non-fluorescent imaging of the uptake of sub-micron-sized polymeric particles by live cells is also demonstrated. Finally, images of fluorescently labelled cells were obtained in TIRF mode, sequentially to images obtained of the same cell in TIRM mode. Visual information gained using TIRF is compared with TIRM to demonstrate that the level of cell structure information obtainable with our total internal reflection microscope is comparable with the TIRF technique.
authors.affiliation: Advanced Drug Delivery Group, School of Pharmacy, University of Nottingham, Nottingham, NG7 2RD, United Kingdom. paxgb@nottingham.ac.uk
authors.forename: G D
authors.initials: GD
authors.lastname: Byrne
authors.forename: M C
authors.initials: MC
authors.lastname: Pitter
authors.forename: J
authors.initials: J
authors.lastname: Zhang
authors.forename: F H
authors.initials: FH
authors.lastname: Falcone
authors.forename: S
authors.initials: S
authors.lastname: Stolnik
authors.forename: M G
authors.initials: MG
authors.lastname: Somekh
mesh_terms: D016475:3T3 Cells; D000818:Animals; D002462:Cell Membrane / Q000378:metabolism / Q000648:ultrastructure; D003470:Culture Media; D004705:Endocytosis / Q000502:physiology*; D005347:Fibroblasts / Q000378:metabolism / Q000648:ultrastructure; D051379:Mice; D018613:Microscopy, Confocal / Q000295:instrumentation / Q000379:methods; D008856:Microscopy, Fluorescence / Q000295:instrumentation / Q000379:methods; D008863:Microspheres
chemical_list: D003470:Culture Media