Magnetic modified cellulose nanocrystals fabricated using ultrasound-coprecipitation: Characterization and application as pickering emulsion stabilizers

Abstract

This study was aimed to investigate the fabrication and properties of magnetic cellulose nanocrystal (MCNC) and further explored its application in stabilizing Pickering emulsions. The MCNC was successfully synthesized by ultrasound-coprecipitation. Combinational morphological and structural techniques were used for characterization. The results highlight the significant role of ultrasonic parameters on the fabrication of MCNC. Ultrasound at 80 W/5 min found to be the optimal condition for MCNC fabrication, resulting in the highest saturation magnetization of up to 83.82 emu/g for obtained MCNC. Compared to cellulose nanocrystals without magnetic modification, MCNC was more efficient in stabilizing oil-in-water (O/W) emulsions due to an increase in wettability (71.4°) and a higher surface charge (−45.1 mV). The dense packaging of emulsion droplets by surrounding MCNC served as a sufficient steric barrier preventing aggregation and coalescence during storage. The emulsion exhibited a dual stimulus-responsive behavior when exposed to a pH/magnetic field. This work provides potential applications of MCNC in the iron fortification of diet or as smart vehicles for the targeted delivery of bioactive compounds.