Investigation of supramolecular stoichiometry and dynamic for inclusion complex of water soluble porphyrin with cucurbit(7)uril by fluorescence correlation spectroscopy

•Tuning of stoichiometry is achieved in fluorescence correlation spectroscopic titration.•CB[7] and cationic porphyrin forms 1:1 to 4:1 stoichiometric complexes sequentially.•Equilibrium binding constant and dynamic parameters are measured for each step.•Higher order complexation is anti-cooperative in nature for the present host–guest system.