The effect of surfactant composition on the chemical and structural properties of nanostructured lipid carriers

Abstract

Fine-tuning the nanoscale structure and morphology of nanostructured lipid carriers (NLCs) is central to improving drug loading and stability of the particles. The role of surfactant charge on controlling the structure, the physicochemical properties and the stability of NLCs has been investigated using three surfactant types (cationic, anionic, non-ionic), and mixed surfactants. Either one, a mixture of two, or a mixture of three surfactants were used to coat the NLCs, with these classified as one, two and three surfactant systems, respectively. The mixed (two and three) surfactant systems produced smaller NLC particles and yielded NLCs with lower crystallinity than the one surfactant system. The combined effects of the ionic and the non-ionic surfactants may play a key role in assisting the lipid-oil mixing, as well as maintaining colloidal repulsion between NLC particles. In contrast, for the three surfactant system, the lipid–oil mixture in the NLCs appeared less homogenous. This was also reflected in the results of the stability study, which indicated that NLC particle sizes in two surfactant systems appeared to be retained over longer periods than for other surfactant systems.

• Nanostructured lipid carriers
• surfactant
• stability
• Raman mapping

Acknowledgements

Authors acknowledge equipment supported from the Center of Excellence for Innovation in Chemistry and the National Nanotechnology Center.

Declaration of interest

The authors report no conflicts of interest. The authors alone are responsible for the content and writing of the article.

This research was financially supported by the National Nanotechnology Center (NANOTEC), Thailand (Research grant number P1011234). K. Karn-orachai is grateful for a scholarship from the Development and Promotion of Science and Technology talents project (DPST).