Bromelain Loaded Lipid-Polymer Hybrid Nanoparticles for Oral Delivery: Formulation and Characterization

Bromelain (Br), a mixture of proteolytic enzymes from pineapple (Ananas comosus), has various therapeutic potentials; however, its low bioavailability has limited the clinical applications specifically in oral delivery as the most common convenient used route of administration. In the present study, a lipopolymeric nanoparticle (NP) containing Br was developed to enhance its stability and oral delivery efficiency. Firstly, Br was loaded into poly (D, L-lactide-co-glycolide acid) (PLGA) and PLGA-phosphatidylcholine (PLGA-PC) NPs using double emulsion solvent evaporation technique. Then, Br integrity and activity were investigated using SDS-PAGE and gelatin test. The stability and release profile of Br from synthetized NPs were evaluated at different pH values of the digestive system. Furthermore, cytotoxicity, cellular uptake, and the amount of Br passage from Caco-2 cells were explored. The results showed PLGA-PC-Br NPs had higher encapsulation efficiency (83%) compared to PLGA-Br NPs (50%). In addition, this NP showed more Br released in neutral (20.36%) and acidic (34%) environments compared to PLGA-Br NPs after 5 days. The delay in the release of Br from PLGA-PC-Br NPs versus the faster release of Br from PLGA-Br formulation could assure that an appropriate concentration of Br has reached the intestine. Intestinal absorption study demonstrated that lipid polymer NPs were able to pass through Caco-2 cells about 1.5 times more (98.4%) than polymeric NPs (70%). In conclusion, PLGA-PC NPs would be considered as a promising lipid-polymer nanocarrier for effective intestinal absorption of Br.