Fabrication and characterization of quercetin loaded almond gum-shellac nanoparticles prepared by antisolvent precipitation

Abstract

A novel nanoparticle (NP) delivery system was designed for encapsulation of bioactive compounds for which quercetin was used as a model. A combination of almond gum (AG) and shellac as biopolymers using the antisolvent method was employed to fabricate the NPs. The influence of several significant preparation factors was investigated. Bare shellac particles showed extreme aggregation when exposed to pH 1.2 (gastric acid conditions), whereas the colloidal system containing 0.7% AG was capable to form NPs with particle size of 197nm with no sign of physio-chemical instability at pH 1.2 and with an encapsulation efficiency (EE) of 78%. Addition of small amounts of polysorbate 80 and Quillaja Saponin led to a drastic decrease in particle size to 90 and 116nm, respectively, with an encapsulation efficiency higher than 98%. The morphology characterization of the NPs with Cryo-SEM revealed that most NPs were spherical with rough surfaces, indicating that AG adsorbed onto the shellac surface as was also reflected by electrokineic measurements. DSC and FTIR analyses indicated that inclusion of quercetin within the NPs coincided with a transition from the crystalline to the amorphous state.To conclude, this study presented the formulation of promising nanocarriers applicable not only in the food but also in the pharmaceutical industry.