Application of HEMA-AAm copolymer to achieve faster optical tissue transparency for 2D/3D fluorescence imaging.

Optical transparency methods can facilitate biological tissue optical imaging, which enabled accurate three-dimensional (3D) signal visualization and quantification of complex biological structures. Unfortunately, existing optical clearing approaches present a compromise between maximizing clearing capability, the preservation of fluorescent protein emission and the speed of sample processing. To address this challenge, we synthesis of a 2-hydroxyethyl methacrylate (HEMA)-acrylamide (AAm) copolymer using antipyrine (ATP) and 2,2'-thiodiethanol (TDE) as solvent, which could embed tissue samples rapidly and highly transparent, and compatible with multiple fluorescence labeling. It can enable volumetric imaging of tissue up to the scale of mice organs, shrinkage duration of the clearing and preserve emission from fluorescent proteins and dyes. This copolymer with suitable toughness and plasticity allows the tissue of interest to be sectioned into thin slices, and histological techniques provide high-resolution two-dimensional (2D) images of cells and subcellular structures. Furthermore, HEMA-AAm copolymer -tissue transparent could distinguish cell structures between healthy and diabetic disease in dye-labeled liver tissues, which provides new insights into pathological diagnosis and analysis. Copolymer provides an environment to facilitate high-resolution 3D/2D fluorescence imaging, which enables the study of cellular and tissue morphology in experimental and clinical conditions of interest.