Imaging the Bio-Distribution of Fluorescent Probes Using Multispectral Epi-Illumination Cryoslicing Imaging

The increasing availability of fluorescent probes for in vivo optical imaging enables the interrogation of complex biological processes in small animals serving as models for human-like tissue function and disease. However, the validation of probe bio-distribution during their development or the study of different disease models, in support of in vivo imaging studies, is not straightforward. The imaging system developed consists of a customized multispectral planar imager that has been adapted on a commercial cryomicrotome and provides a powerful modality for ex vivo imaging of small animals. The ability to capture 3D anatomical (color) and fluorescence volumetric distributions of multiple fluorescent markers in high resolution is showcased. Serving both as a method for accurately imaging the bio-distribution of multiple fluorescent agents inside organisms and as a modality for the validation of non-invasive methods, multispectral cryoslicing imaging offers useful insights to ex vivo optical imaging of molecular probes.