Surface behavior and bulk properties of aqueous chitosan and type-B gelatin solutions for effective emulsion formulation

Jagadish Chandra Roy; Fabien Salaün; Stéphane Giraud; Ada Ferri; Jinping Guan

doi:10.1016/j.carbpol.2017.06.001

Surface behavior and bulk properties of aqueous chitosan and type-B gelatin solutions for effective emulsion formulation

Carbohydr Polym. 2017 Oct 1:173:202-214. doi: 10.1016/j.carbpol.2017.06.001. Epub 2017 Jun 3.

Authors

Jagadish Chandra Roy¹, Fabien Salaün², Stéphane Giraud², Ada Ferri³, Jinping Guan⁴

Affiliations

¹ University Lille Nord de France, F-5900 Lille, France; ENSAIT, GMTEX, F-59100, Roubaix, France; Department of Applied Science and Technology, Politecnico di Torino, Italy; College of Textile and Clothing Engineering, Soochow University, Suzhou, Jiangsu, 215123, China. Electronic address: jagadish-chandra.roy@ensait.fr.
² University Lille Nord de France, F-5900 Lille, France; ENSAIT, GMTEX, F-59100, Roubaix, France.
³ Department of Applied Science and Technology, Politecnico di Torino, Italy.
⁴ College of Textile and Clothing Engineering, Soochow University, Suzhou, Jiangsu, 215123, China.

PMID: 28732859
DOI: 10.1016/j.carbpol.2017.06.001

Abstract

The behavior of aqueous chitosan (CH), type-B gelatin (GB) and CH-GB coacervate was studied on oil-in-water emulsion formulation at various pH and concentration ratio. The coacervate was formed by phase separation at ratios CH:GB, 1:10 to 1:1 with total biopolymer concentrations of 0.55%-1.0% (w/v) at pH 4.0-5.5. Soluble complexes were formed below pH 5.0 and coacervate formation was confirmed at pH 5.0 and above by zeta potential and UV-spectroscopy measurements. The coacervate formation was found maximum at the CH-GB ratios of 1:10 and 1:5 at pH 5.5. Formulated emulsions (>10μm droplets) using 1% (w/v) chitosan and GB were found stable (+52.5mv and creaming index 86%) and unstable respectively. Emulsion stabilized by mixed CH:GB 1:5 (3%w/v) had no creaming effect. The instability was attributed to the lower surface activity (K=5.0Lg^-1) of pure GB compared to CH (K=14.3Lg^-1). The formulation and methods can successfully tune the stability of the emulsions.

Keywords: Chitosan; Coacervate; O/W emulsion; Turbidity; Type-B gelatin; Zeta potential.