Effect of Chitosan Coating on PLGA Nanoparticles for Oral Delivery of Thymoquinone: In Vitro, Ex Vivo, and Cancer Cell Line Assessments

In the present study, thymoquinone (TQ)-encapsulated chitosan- (CS)-coated poly(d,l-lactide-co-glycolide) (PLGA) nanoparticles (NPs) were formulated using the emulsion evaporation method. NPs were optimized by using 33-QbD approach for improved efficacy against breast cancer. The optimized thymoquinone loaded chitosan coated Poly (d,l-lactide-co-glycolide) nanoparticles (TQ-CS-PLGA-NPs) were successfully characterized by different in vitro and ex vivo experiments as well as evaluated for cytotoxicity in MDA-MB-231 and MCF-7 cell lines. The surface coating of PLGA-NPs was completed by CS coating and there were no significant changes in particle size and entrapment efficiency (EE) observed. The developed TQ-CS-PLGA-NPs showed particle size, polydispersibility index (PDI), and %EE in the range between 126.03–196.71 nm, 0.118–0.205, and 62.75%–92.17%. The high and prolonged TQ release rate was achieved from TQ-PLGA-NPs and TQ-CS-PLGA-NPs. The optimized TQ-CS-PLGA-NPs showed significantly higher mucoadhesion and intestinal permeation compared to uncoated TQ-PLGA-NPs and TQ suspension. Furthermore, TQ-CS-PLGA-NPs showed statistically enhanced antioxidant potential and cytotoxicity against MDA-MB-231 and MCF-7 cells compared to uncoated TQ-PLGA-NPs and pure TQ. On the basis of the above findings, it may be stated that chitosan-coated TQ-PLGA-NPs represent a great potential for breast cancer management.