Ultrasonic assisted water-in-oil emulsions encapsulating macro-molecular polysaccharide chitosan: Influence of molecular properties, emulsion viscosity and their stability

Hydrodynamic cavitation: A feasible approach to intensify the emulsion cross-linking process for chitosan nanoparticle synthesis

“…From a practical application perspective, the particle size and the PDI representing the size distribution of chitosan NPs have an important relationship with their function and purpose, e.g., target-oriented release for the drug [9] , [32] . The oil phases used as a suspension media in the emulsion cross-linking process can greatly affect the droplet size, uniformity, and stability of W/O emulsions due to their different physical properties (e.g., viscosity) [7] , [9] , [30] , which can indirectly affect the particle size, the size distribution, and the surface morphology of chitosan NPs during the subsequent cross-linking reaction process.…”

“…The HC-induced formation of W/O nanoemulsion containing CS was performed with reference to our previous work [30] . First, CS was dissolved in an aqueous acidic media at a given pH value to prepare the solutions, and Span 80 was added to the oil phase with stirring at 55 ± 5 °C for 5 min.…”

“…The droplet size and size distribution of HC-produced W/O emulsions containing CS were measured using DLS on the Zetasizer nano S90 (Malvern Instruments, UK), as described previously [30] . The Z-average diameter represents the mean droplet size.…”

“…The change in chemical bonds of oil molecules was tested using Fourier transform infrared spectroscopy (FTIR, Perkin Elmer, USA) [30] , [31] . The FTIR spectra of pure palm oil and palm oil after the formation of HC-produced chitosan NPs were studied, and FTIR spectrophotometry was carried out with a scan range of 4000–400 cm −1 .…”

“…The current study is a continuation of our previous research [30] , in which a uniform W/O nanoemulsion containing CS was prepared using an ultrasonic reactor. The main objective was to evaluate the feasibility of introducing controlled HC to the emulsion cross-linking process to produce uniformly sized chitosan NPs.…”