Cationic nanocapsule suspension as an alternative to the sublingual delivery of nifedipine.

Nifedipine (NIFE) is a calcium channel blocker drug used to treat cardiovascular diseases, angina, and hypertension. However, NIFE is photolabile, has a short biological half-life, low aqueous solubility, and undergoes an intense first-pass effect, compromising its oral bioavailability. Thus, this study aimed to develop NIFE-loaded nanocapsules for sublingual administration. Nanocapsule suspensions of Eudragit RS100 and medium chain triglycerides containing NIFE were prepared by the interfacial deposition of preformed polymer technique. The developed formulations showed particle size around 170 nm, polydispersity index below 0.2, positive zeta potential, and acid pH. The NIFE content was 0.98 ± 0.03 mg/mL, and the encapsulation efficiency was 99.9%. The natural light photodegradation experiment showed that the nanocapsules were able to provide NIFE photoprotection. The nanocapsules reduced the cytotoxicity of NIFE and showed no genotoxic effects in the model. Through the HET-CAM test, the formulations were classified as non-irritating. The developed nanocapsule suspension demonstrated a controlled release of NIFE and mucoadhesive potential. The permeation assay showed that the nanocapsules favored the NIFE permeation to the receptor compartment. In addition, the nanocapsules provided greater drug retention in the mucosa. Thus, the development of polymeric nanocapsule suspensions showed that this system could be a promising platform for NIFE sublingual administration.