Role of the templating approach in influencing the suitability of polymeric nanocapsules for drug delivery: LbL vs SC/MS.

Polymer nanocapsules play an increasingly important role for drug delivery applications. Layer-by-layer (LbL) templated synthesis has received the widest attention to fabricate polymer nanocapsules. However, for drug delivery applications, the LbL approach may not necessarily offer the optimum nanocapsules. We make the first attempt to compare the LbL approach with a more recently developed solid core/mesoporous shell (SC/MS) templated approach in context of their suitability for construction of sub-500 nm sized capsules for drug delivery applications. The nanocapsules of chitosan, poly(allylamine hydrochloride) (PAH), and poly(sodium 4-styrenesulfonate) (PSS) are fabricated using LbL and SC/MS templating approaches and loaded with curcumin, a model lipophilic anticancer drug. The influence of the templating approach on capsule aggregation, polymer loading, drug loading, cellular uptake, and therapeutic efficacy against MCF-7 breast cancer cells is compared in an effort to identify the most suitable fabrication method and polymer material for drug delivery applications. In combination, among different tested nanocapsules, chitosan nanocapsules fabricated using the SC/MS approach are found to be the most promising candidate that demonstrates the optimum cytotoxic efficiency and significant potential for drug delivery.