polymeric drug delivery systems / physico-chemical characteristics / perturbation free energy / dilute solutions / gas-saturated solution / free energy / drug delivery systems / self-microemulsifying drug delivery systems / mass action law / conformational free energy / gas antisolvent / in vivo biological studies oral delivery systems / colloidal systems / physico-chemical characterization / chemical manufacturing / biopharmaceutical properties / pharmaceutical formulations / technology grinding / parenteral delivery systems / colloidal lipid carrier / food / /