Development and characterization of nanocapsules comprising dodecyltrimethylammonium chloride and κ-carrageenan

The aim of this work was to develop and characterize a new type of nanocapsules. To this end, a nanoemulsion bearing an oily core (Miglyol 812) was obtained by spontaneous emulsification and stabilized by dodecyl-trimethylammonium chloride (DTAC), a commercial cationic surfactant; this nanoemulsion was coated with proportionally very small amounts of κ-carrageenan (at molar charge ratios of Z ≤ 0.0045) that interact predominantly by an electrostatic mechanism with the positively charged sites at the polar heads of DTAC at the nanoemulsion's surface to harness nanocapsules of average size ∼250–330 nm and zeta potential (ζ) ranging from ∼+80 to +7 mV. The potential application of the new type of developed nanosystems as drug delivery vehicles has yet to be investigated and fully realized.

A model proposed to describe the interaction between κ-carrageenan and DTAC-stabilized nanoemulsion; it explains the influence of the polyelectrolyte attached at the nanocapsule's surface on the physical properties.Figure optionsDownload as PowerPoint slideHighlights
► We succeeded to develop new prototype of nanocapsules based on the electrostatic interaction of oppositely charged κ-carrageenan polyelectrolyte with the surface of DTAC-stabilized nanoemulsion.
► The interaction is extremely effective as even at Z values of ∼0.0045 (Z = [SO3−]/[(CH3)3N+]), the surface of the nanocapsules becomes almost completely neutralized.
► The potential application of this new type of nanocapsules in drug delivery seems promising.