In this paper, we describe the combination of ultraviolet (UV) spectroscopy with the optical clearing technique toinduce new tissue windows, evaluate their efficiency, study thediffusion properties of agents and discriminate cancer. The use ofhighly concentrated glycerol solutions has induced high efficiencyclearing effects in the UV, both in human colorectal and gingivaltissues. The protein dissociation rate obtained for colorectal tissueswas approximately 3 times higher in pathological than in normalmucosa and the kinetics of diffuse reflectance in the UV allowedto estimate the diffusion coefficient for water in gingival mucosa atglycerol action as (1.78 ± 0.26) × 10−6 cm2/s.