Devices based on light emitting fabrics dedicated to PDT preclinical studies

Whether preclinical studies either involve a cell or animal model, the distribution of light plays a determinant role in the reproducibility of results of photodynamic therapy (PDT) studies. Unfortunately, only few illumination devices dedicated to preclinical studies are available and are for the most, very expensive. Most research teams use home-made solutions that may not always be reproducible because of undefined light distribution, additive thermal emission, or unsuitable for shapes and volumes to illuminate. To address these issues, we developed illumination devices dedicated to our preclinical studies, which embed knitted light emitting fabrics (LEF) technology. LEF technology offers a homogeneous light distribution, without thermal emission and can be coupled with various light sources allowing investigation of several PDT modalities (irradiance, wavelength, illumination duration/mode). For in-vitro studies, we designed light plates, each allowing illumination of up to four 96-cells plates. For in-vivo studies, we designed mice boxes allowing three animals placement in prone position, equally surrounded by LEF and ensuring homogeneous extracorporeal illumination. Optical validation was performed and reproducibility of both preclinical systems were assessed. Both systems can deliver homogeneous light with an irradiance that can reach several mW/cm2, with varying durations and wavelengths. First results of preclinical studies demonstrate a high reproducibility, with an easy setup, and a great adaptability of illumination modalities with these devices based on light emitting fabrics.