Magnetic cellulose nanocrystal stabilized Pickering emulsions for enhanced bioactive release and human colon cancer therapy

Stimuli-responsive drug release and controlled delivery play crucial roles in enhancing the therapeutic efficacy and lowering over-dosage induced side effects. In this paper, we report magnetically-triggered drug release and in-vitro anti-colon cancer efficacy of Fe3O4@cellulose nanocrystal (MCNC)-stabilized Pickering emulsions containing curcumin (CUR). The loading efficiency of CUR in the micron-sized (≈7 μm) MCNC-stabilized Pickering emulsions (MCNC-PE) template was found to be 99.35%. The drug release profiles showed that the exposure of MCNC-PE to external magnetic field (EMF) (0.7 T) stimulated the release of bioactive from MCNC-PE achieving 53.30 ± 5.08% of the initial loading over a 4-day period. The MTT assay demonstrated that the CUR-loaded MCNC-PE can effectively inhibits the human colon cancer cells growth down to 18% in the presence of EMF. The formulation also resulted in 2-fold reduction on the volume of the 3-D multicellular spheroids of HCT116 as compared to the control sample. The MCNC particle was found to be non-toxic to brine shrimp up to a concentration of 100 μg/mL. Our findings suggested that the palm-based MCNC-PE could be a promising yet effective colloidal drug delivery system for magnetic-triggered release of bioactive and therapeutics.