In Situ Cell Detection Using Terahertz Near-Field Microscopy

Abstract

The photoconductive antenna microprobe-based terahertz (THz) near-field scanning microscope has proven to overcome the diffraction limit and demonstrated the potential in distinguishing cellular types and states. Here, using the onion epidermal cells as a sample model, detection of single epithelial cell in the onion skin has been realized at amplitude signal around 1 THz. The boundaries of the target cells in a monolayer onion epidermis are clearly depicted with the spatial resolution of 9 <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">μ</i> m (λ/33). Differentiated THz dielectric response shows clearly the distinctive intracellular and intercellular regions, mainly related to the biowater distribution and cellular heterogeneity, which can be used for <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">in situ</i> subcellular identification <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">.</i> This finding may have significant implications for the advancement of THz near-field high-resolution bioimaging technology.