title: Correlative fluorescence microscopy and scanning transmission electron microscopy of quantum-dot-labeled proteins in whole cells in liquid.
abstract: Correlative fluorescence microscopy and transmission electron microscopy (TEM) is a state-of-the-art microscopy methodology to study cellular function, combining the functionality of light microscopy with the high resolution of electron microscopy. However, this technique involves complex sample preparation procedures due to its need for either thin sections or frozen samples for TEM imaging. Here, we introduce a novel correlative approach capable of imaging whole eukaryotic cells in liquid with fluorescence microscopy and with scanning transmission electron microscopy (STEM); there is no additional sample preparation necessary for the electron microscopy. Quantum dots (QDs) were bound to epidermal growth factor (EGF) receptors of COS7 fibroblast cells. Fixed whole cells in saline water were imaged with fluorescence microscopy and subsequently with STEM. The STEM images were correlated with fluorescence images of the same cellular regions. QDs of dimensions 7x12 nm were visible in a 5 microm thick layer of saline water, consistent with calculations. A spatial resolution of 3 nm was achieved on the QDs.
authors.affiliation: Department of Chemistry, Vanderbilt University, Nashville, Tennessee 37235, USA.
authors.forename: Madeline J
authors.initials: MJ
authors.lastname: Dukes
authors.forename: Diana B
authors.initials: DB
authors.lastname: Peckys
authors.forename: Niels
authors.initials: N
authors.lastname: de Jonge
mesh_terms: D000818:Animals; D019556:COS Cells; D002522:Chlorocebus aethiops; D066246:ErbB Receptors / Q000378:metabolism*; D005057:Eukaryotic Cells / Q000378:metabolism*; D046210:Microfluidic Analytical Techniques; D017348:Microscopy, Electron, Scanning Transmission / Q000295:instrumentation / Q000379:methods*; D008856:Microscopy, Fluorescence / Q000295:instrumentation / Q000379:methods*; D045663:Quantum Dots; D013194:Staining and Labeling
chemical_list: D066246:ErbB Receptors