Abstract
Niosomes were prepared using a novel supercritical carbon dioxide based method to simultaneously encapsulate ferrous sulfate and vitamin D3 as hydrophilic and hydrophobic cargo, respectively. Vesicle particle size was determined to be bimodal with peak diameters of 1.44 ± 0.16 μm and 7.21 ± 0.64 μm, with the smaller peak comprising 98.8% of the total niosomal volume. Encapsulation efficiency of ferrous sulfate was 25.1 ± 0.2% and encapsulation efficiency of vitamin D3 was 95.9 ± 1.47%. Physical stability of the produced niosomes was assessed throughout a storage period of 21 days. Niosomes showed good physical stability at 20 °C, but storage at 4 °C showed an initial burst release, indicating possible rupture of the niosomal membrane. The Korsmeyer–Peppas equation was used to model the release of ferrous sulfate over time at both storage temperatures.
Acknowledgements
The authors would like to thank Heartland Assays for their assistance with the vitamin D3 sample analysis.
Declaration of interests
The authors report no declaration of interests. This work was supported in part by the Cornell Center for Materials Research with funding from the NSF MRSEC program (DMR-1120296).