Plasmon-Enhanced Autofluorescence Imaging of Organelles in Label-Free Cells by Deep-Ultraviolet Excitation.

Abstract

We demonstrate the observation of organelles in label-free cells on an aluminum thin film using deep-ultraviolet surface plasmon resonance (DUV-SPR). In particular, the Kretschmann configuration is used for the excitation of DUV-SPR. MC3T3-E1 cells are directly cultured on the aluminum thin film, and DUV-SPR leads to autofluorescence of in the label-free MC3T3-E1. We found that nucleic acid and mitochondria in these label-free MC3T3-E1 cells quite strongly emit the autofluorescence as a result of DUV-SPR. Yeast cells are also deposited on the aluminum thin film. Tryptophan and mitochondrial nicotinamide adenine dinucleotide (NADH) in the yeast cells are subsequently excited, and their autofluorescence is spectrally analyzed in the UV region. On the basis of these results, we conclude that DUV-SPR constitutes a promising technique for the acquisition of highly sensitive autofluorescence images of various organelles in the cells.