title: Modified cellulose nanocrystal for vitamin C delivery.
abstract: Cellulose nanocrystal grafted with chitosan oligosaccharide (CNC-CSOS) was used to encapsulate vitamin C and prepare CNCS/VC complexes using tripolyphosphte via ionic complexation. The stability of vitamin C and the antioxidant activity of the CNCS/VC complexes were elucidated. The formation of the complex was confirmed using DSC and UV-vis spectrophotometry, and TEM was used to study the morphology of the complexes. The encapsulation efficiency of vitamin C at pH 3 and 5 was 71.6% ± 6.8 and 91.0 ± 1.0, respectively. Strong exothermic peaks observed in isothermal titration calorimetric (ITC) studies at pH 5 could be attributed to additional electrostatic interactions between CNC-CSOS and vitamin C at pH 5. The in vitro release of vitamin C from CNCS/VC complexes showed a sustained release of up to 20 days. The vitamin C released from CNCS/VC complex displayed higher stability compared with the control vitamin C solution, and this was also confirmed from the ITC thermograms. CNC-CSOS possessed a higher scavenging activity and faster antioxidant activity compared with its precursors, i.e., oxidized CNC and CSOS and their physical mixtures. Complexing vitamin C into CNC-CSOS particles yielded a dynamic antioxidant agent, where the vitamin C is released over time and displayed sustained antioxidant properties. Therefore, CNCS/VC can potentially be used in cosmeceutical applications as topical formulations.
authors.affiliation: Department of Chemical Engineering, Waterloo Institute for Nanotechnology, University of Waterloo, 200 University Avenue West, Waterloo, Ontario, N2L 3G1, Canada, spakhlag@uwaterloo.ca.
authors.forename: Seyedeh Parinaz
authors.initials: SP
authors.lastname: Akhlaghi
authors.forename: Richard M
authors.initials: RM
authors.lastname: Berry
authors.forename: Kam Chiu
authors.initials: KC
authors.lastname: Tam
mesh_terms: D000975:Antioxidants / Q000737:chemistry; D001205:Ascorbic Acid / Q000737:chemistry*; D002482:Cellulose / Q000737:chemistry*; D002626:Chemistry, Pharmaceutical / Q000379:methods; D048271:Chitosan / Q000737:chemistry; D003692:Delayed-Action Preparations / Q000737:chemistry; D016503:Drug Delivery Systems / Q000379:methods; D006863:Hydrogen-Ion Concentration; D053758:Nanoparticles / Q000737:chemistry*; D009844:Oligosaccharides / Q000737:chemistry; D055672:Static Electricity
chemical_list: D000975:Antioxidants; D003692:Delayed-Action Preparations; D009844:Oligosaccharides; D002482:Cellulose; D048271:Chitosan; D001205:Ascorbic Acid