The Dual-Mode Imaging of Nanogold-Labeled Cells by Photoacoustic Microscopy and Fluorescence Optical Microscopy

Photoacoustic microscopy is dominantly sensitive to the endogenous optical absorption, while a fluorescence optical microscopy can detect the fluorescence emission to obtain the image of a sample. To some extent, the physical processes of the 2 methods are opposite, one is absorption and another is emission, but both can be used to image cells. In this article, a simultaneous dual-mode imaging system of photoacoustic microscopy and fluorescence optical microscopy is set up to image tobacco cells. Furthermore, gold nanoparticles, which have a large absorption coefficient and enough fluorescence emission with wavelength of 512 nm, are used to label certain drugs and added to the tobacco cells. Then based on the simultaneous dual-mode microscopy imaging system, the photoacoustic microscopy and fluorescence optical microscopy images of gold nanoparticle-labeled tobacco cells are obtained. The final purpose of this experimental research is to detect if the labeled drugs can enter the cells by the positions of the gold nanoparticles. This will help the experts to deliver organic pesticide more accurately and effectively. The experimental results show that by gold nanoparticle labeling technology, the imaging quality of photoacoustic microscopy and fluorescence optical microscopy can be improved, which indicates that the drugs probably enter the tobacco cells successfully.