Porous silicon microcarriers for extended release of metformin: Design, biological evaluation and 3D kinetics modeling

•Metformin adsorption induced a positive charge on PSi surface.•Thermally oxidized PSi surface extended metformin delivery along 26 h.•Diffusional model was applied to accurately predict MET loading and release kinetics.•MET-μPSip microcarriers did not induce inflammatory processes.•In vivo studies of MET-µPSip carrier showed a sustained hypoglycemic effect.