Transmission electron microscopy (TEM) actively analyzes matter by magnifying its smallest structures, offering unparalleled detail at the atomic scale compared to optical microscopes, which rely on visible light. By accelerating electrons through a strong electromagnetic field, TEM achieves resolutions magnitudes higher than optical microscopy, as electrons possess significantly shorter wavelengths, about 100,000 times smaller than visible light. This enables TEM to magnify nanometer-scale structures up to 50 million times. To produce a TEM image, a high-energy electron beam is propelled through an ultra-thin "electron transparent" sample, usually less than 100 nm thick. Throughout the microscope's column, a series of electromagnetic lenses and apertures meticulously focus the beam onto the sample, minimizing distortions, and then magnify the resulting image onto either a phosphor screen or a specialized camera.

The transmission electron microscope (TEM) is employed to visualize thin specimens, such as tissue sections and molecules, allowing electrons to pass through and form a projection image. Similar to the conventional light microscope, TEM shares many characteristics. It is utilized for various purposes, including imaging the interior of cells, examining the structure of protein molecules, investigating the organization of molecules in viruses and cytoskeletal filaments through negative staining techniques, and studying the arrangement of protein molecules in cell membranes via freeze-fracture methods.

Dr. Amanda Sevcik

Dinny Stevens

Ameh, T., Zarzosa, K., Dickinson, J., Braswell, W. E., & Sayes, C. M. J. F. i. M. (2023). Nanoparticle surface stabilizing agents influence antibacterial action. 14, 1119550.

Lyons-Darden T, Heim KE, Han L, Haines L, Sayes CM, Oller AR. Bioaccessibility of Metallic Nickel and Nickel Oxide Nanoparticles in Four Simulated Biological Fluids. Nanomaterials. 2024 May 17;14(10):877.

Pingrey B, Ede JD, Sayes CM, Shatkin JA, Stark N, Hsieh YL. Aqueous exfoliation and dispersion of monolayer and bilayer graphene from graphite using sulfated cellulose nanofibrils. RSC advances. 2024;14(14):9860-8.

Guo M, Ede JD, Sayes CM, Shatkin JA, Stark N, Hsieh YL. Regioselectively Carboxylated Cellulose Nanofibril Models from Dissolving Pulp: C6 via TEMPO Oxidation and C2, C3 via Periodate–Chlorite Oxidation. Nanomaterials 2024, 14, 479.

Mulenos MR, Zechmann B, Sayes CM. Sample preparation utilizing sputter coating increases contrast of cellulose nanocrystals in the transmission electron microscope. Microscopy. 2019 Dec 3;68(6):471-4.

Lujan H, Mulenos MR, Carrasco D, Zechmann B, Hussain SM, Sayes CM. Engineered aluminum nanoparticle induces mitochondrial deformation and is predicated on cell phenotype. Nanotoxicology. 2021 Oct 21;15(9):1215-32.

Sayes CM, Lujan H. Characterizing the Nano‐Bio Interface Using Microscopic Techniques: Imaging the Cell System is Just as Important as Imaging the Nanoparticle System. Current Protocols in Chemical Biology. 2017 Jan;9(3):213-31.

MULENOS MR, ZECHMANN B, SAYES CM. A RAPID METHOD TO CHARACTERIZE CELLULOSE FIBRILS USING SCANNING ELECTRON MICROSCOPY. Texas Journal of Microscopy. 2021 Jan 1;52(1).

Sayes CM, Sooresh A, Meissner KE. Physicochemical characteristics of two prototypical home-use consumer products containing engineered nanomaterials. Journal of Environmental & Analytical Toxicology. 2015 Jan 1;5(6):1.