Study on the degradation of chitosan by pulsed electric fields treatment

Abstract

Abstract Chitosan solution was processed by applying pulsed electric fields (PEF) with different strengths up to 25 kV cm − 1 . Changes of the physicochemical properties of chitosan, such as molecular weight and crystallinity degree, were measured by analyses of scanning electron microscopy (SEM), viscosity molecular weight ( M v ), X-ray diffractometry (XRD), FTIR and UV spectra. The results showed that after being treated at 25 kV cm − 1 , the chitosan granules were significantly deformed with many pits and cracks appeared on the surface. M v was decreased with the increasing electric field strength, for example, the M v was decreased from 2.81 × 10 5 Da (initial chitosan) to 1.54 × 10 5 Da after the PEF treatment at 25 kV cm − 1 . Meanwhile, the crystalline region of the treated sample was significantly damaged from XRD patterns. All results showed that the PEF technique is a possible method to obtain low molecular-weight chitosan. Industrial Relevance Chitosan solution was treated by using pulsed electric fields (PEF) with different strengths up to 25 kV·cm -1 . Changes of the physicochemical properties of chitosan were measured by analyses of scanning electron microscopy (SEM), viscosity molecular weight (M v ), X-ray diffractometry (XRD), FTIR and UV spectra. The results showed that the PEF technique is a promising method for scale-up industrial manufacture of low-molecular-weight chitosan.