Phillips, JustinVenter, Jaco-LouisAtanasova, Maria TodorovaWesley-Smith, JamesOosthuizen, HesterEmmambux, Mohammad NaushadDu Toit, Elizabeth LouisaFocke, Walter Wilhelm2021-08-042021-08-042020-03Phillips, J., Venter, J., Atanasova, M.T. et al. 2020, 'Dextrin nanocomposites as matrices for solid dosage forms', ACS Applied Materials and Interfaces 2020, 12, 14, 16969–16977.1944-8244 (print)1944-8252 (online)10.1021/acsami.0c02061http://hdl.handle.net/2263/81143Safe application of water-insoluble acaricides requires fast release from solid dosage systems into aquatic environments. Dextrin is a water-soluble form of partially hydrolyzed starch, which may be used as matrix material for these systems if retrogradation can be inhibited by the inclusion of nanofillers. Several glycerol-plasticized thermoplastic dextrin-based nanocomposites were prepared with a twin-screw extrusion-compounding process. The nanofillers included a layered double hydroxide (LDH), cellulose nanofibers (CNF), and stearic acid. The time-dependent retrogradation of the compounds was monitored by X-ray diffraction (XRD) and dynamic mechanical thermal analysis (DMA). XRD showed that composite samples that included stearic acid in the formulation led to the formation of an amylose-lipid complex and a stable crystallinity during aging. The most promising nanocomposite included both stearic acid and CNF. It was selected as the carrier material for the water-insoluble acaricide Amitraz. Fast release rates were observed for composites containing 5, 10, and 20% (w/w) of the pesticide. A significant reduction in the particle size of the released Amitraz powder was observed, which is ascribed to the high-temperature compounding procedure.en© 2020 American Chemical SocietyLayered double hydroxide (LDH)Cellulose nanofibers (CNF)Stearic acidX-ray diffraction (XRD)Dynamic mechanical thermal analysis (DMA)DextrinSolid dosage formAcaricideThemoplastic starchPostprint Article