Development of nanostructured lipid carriers for the encapsulation and controlled release of vitamin D3

Nanostructured lipid carriers (NLCs) for encapsulating vitamin D3 (VD3), a lipophilic vitamin, were successfully fabricated by hot high pressure homogenization. The physicochemical properties of the VD3-NLCs were characterized, and the release profiles of VD3 in simulated gastrointestinal fluids were investigated. Optimum VD3-NLCs were obtained with a small diameter (132.9nm), a high zeta potential (-41.90mV), and a high encapsulation efficiency (85.6%). The stability of the VD3-NLCs was tested during 20days of storage at 25°C under a wide range of pHs. In vitro digestion in simulated gastrointestinal fluids demonstrated their capability for controlled release because the NLCs were able to remain stable and protect the VD3 in simulated stomach fluid, but released more than 90% of the VD3 in simulated intestinal fluid. Therefore, the developed NLCs are promising carriers for increasing the oral bioavailability of VD3.