Pickering Emulsion-Assisted Spherical Crystallization of Ibuprofen
- Jiayuan Wang,
- Wenqi Cao,
- Jianli Wang,
- Lingyu Zhu
Abstract
Spherical crystallization is a promising process intensification
technique, where surfactant is an important ingredient in formulation
but needs to be used carefully due to toxicological reasons. This work
proposes to substitute the conventionally used surfactants by adopting
colloidal particles stabilized Pickering emulsions for spherical
crystallization. A representative system is selected for study, where
silica nanoparticles are prepared to stabilize emulsions and evaporative
crystallization of ibuprofen is carried out. Depletion attraction is
exploited to improve the Pickering emulsion stability for better
confining on crystallization with two depletants PEG and PVA tested.
Crystal products from the emulsions prepared with silica nanoparticles
and the non-ionic surfactant Tween 20 are compared. The results show
that depletion attraction is helpful for producing stable Pickering
emulsions with high dispersed phase fraction and mono-dispersed
ibuprofen spherical agglomerates. Silica nanoparticles contribute to
reduced induction time by boosting heterogeneous nucleation and mitigate
secondary agglomeration possibly by steric effects.