Photoactivatable Fluorescent Dyes with Hydrophilic Caging Groups and Their Use in Multicolor Nanoscopy
Alexey N. Butkevich, Michael Weber, Angel R. Cereceda Delgado, Lynn M. Ostersehlt, Elisa D’Este, Stefan W. Hell
Abstract
We propose a series of fluorescent dyes with hydrophilic carbamate caging groups that undergo rapid photoactivation under UV (≤400 nm) irradiation but do not undergo spurious two-photon activation with high-intensity (visible or infrared) light of about twice the wavelength. The caged fluorescent dyes and labels derived therefrom display high water solubility and convert upon photoactivation into validated super-resolution and live-cell-compatible fluorophores. In combination with popular fluorescent markers, multiple (up to six)-color images can be obtained with stimulated emission depletion nanoscopy. Moreover, individual fluorophores can be localized with precision <3 nm (standard deviation) using MINSTED and MINFLUX techniques.