Article 9 unclassified drug controlled study 7 nonhuman 6 Permeability 4 chemistry 4 drug effect 4 human 4 human cell 4 metabolism 4 permeability 4 cell membrane permeability 3 particle size 3 Animals 2 Caco-2 cell line 2 Humans 2 Steam 2 animal 2 animal cell 2 animal tissue 2 binding affinity 2 cell viability 2 chemical phenomena 2 chemical structure 2 comparative study 2 crystal structure 2 drug absorption 2 drug bioavailability 2 drug penetration 2 drug synthesis 2