AA	Ascorbic acid
AC	Apical compartment
ACEI	Angiotensin-converting enzyme inhibitor
API	Active pharmaceutical ingredient
BC	Basolateral compartment
BCS	Biopharmaceutics Classification System
CAP	Captopril
CHI	Chitosan
CHI-Ac	Chitosan acetate
CHI-Asc	Chitosan ascorbate
DoE	Design of Experiments
FT-IR	Fourier transform infrared spectroscopy
GLY	Glycerol
HATR	Horizontal attenuated total reflectance
HBSS	Hank’s balanced salt solution
ICH	International Council for Harmonization
NR	Neutral Red
PB	Phosphate buffer
Ph.Eur.	European Pharmacopeia
QbD	Quality by Design
RH	Relative humidity
SD	Standard deviation