Using Fda-Approved Drugs As Off-Label Fluorescent Dyes For Optical Biopsies: From In Silico Design To Ex Vivo Proof-Of-Concept

Optical biopsies bring the microscope to the patient rather than the tissue to the microscope, and may complement or replace the tissue-harvesting component of the traditional biopsy process with its associated risks. In general, optical biopsies are limited by the lack of endogenous tissue contrast and the small number of clinically approved in vivo dyes. This study tests multiple FDA-approved drugs that have structural similarity to research dyes as off-label in situ fluorescent alternatives to standard ex vivo hematoxylin & eosin tissue stain. Numerous drug-dye combinations shown here may facilitate relatively safe and fast in situ or possibly in vivo staining of tissue, enabling real-time optical biopsies and other advanced microscopy technologies, which have implications for the speed and performance of tissue- and cellular-level diagnostics.