The cellular entrance and exit of bioactive molecules are key-issues for living organisms since they encompass crucial processes (cell signaling and communication, cellular excretory activity and drug delivery…) Whatever the nature of the uptake/release process, unsolved questions remain on the quantification of the species crossing the plasma membrane and on the description of the mechanistic steps involved at short timescales. Our project relies on the merging and coupling of electrochemical and fluorescence techniques to provide a characterization of dynamic processes related to the internalization and the release of biomolecules. We propose an integrated approach where the quest for quantitative and time resolved information on transport governs both the design/preparation of adequate redox fluorescent probes and the conception of suitable setups. This integrated “from the probe to the application” approach is aimed at making fluorescence and electrochemistry a designable, controllable and quantitative dual tool to explore transport issues in both mimetic and living systems.