Multiphoton microscopy for 3D imaging of nanofibres stained with resveratrone

Resveratrone is a new compound formed by the UV radiation of trans-resveratrol [1]. It has already been determined to have large values of absorption cross-section making it suitable for bio-imaging and multi-colour labelling [1]. In this work, we study the nonlinear properties of resveratone by two-photon fluorescence spectroscopy and we demonstrate its application for labelling and imaging the three-dimensional (3D) structure of cellulose acetate nanofibers. These fibres are used as scaffolds in tissue engineering where the two-photon laser microscopy gains its advantage from its intrinsic three-dimensional resolution and the absence of background fluorescence. The aim of the work is to image the 3D arrangement of the fibres and obtain the penetration length of the cultured cells in the scaffold. The imaging was performed using a pulsed Ti-Sapphire laser in a modified confocal microscope setup. We have also demonstrated a labelling process where the resveratrone is already produced directly on the nanofibers by UV irradiation. The results obtained clearly show the details of the cell and nanofibers arrangements and other potentials for 3D cell imaging for different samples.