The physicochemical properties of chitosan prepared by microwave heating

Abstract

The aim of this study was to compare the physicochemical properties of chitosan prepared by microwave and water bath heating with an equivalent quantity of heat intake. The structure and physicochemical properties of the chitosan obtained by these two methods were characterized by Fourier transform infrared spectroscopy (FTIR), X‐ray diffractometry (XRD), gel permeation chromatography (GPC), and scanning electron microscopy (SEM). The FTIR and XRD patterns show that there was no significant difference in the structure of chitosan produced by the two heat sources. The results showed that chitosan with 73.86% deacetylation was successfully prepared by microwave heating within 60 min, while a longer time of 180 min was required for the preparation of chitosan with the same deacetylation degree (74.47%) using the conventional heating method under the same heating rate. Even under the same temperature conditions, microwave technology can greatly reduce the reaction time by approximately 1/3, while the chitosan produced by microwaves can obtain relatively low molecular weight and viscosity. These results showed that microwaves may efficiently promote complete chemical reactions by the friction heating mechanism generated by molecular vibration beyond a rapid heating source, turning into a more efficient, energy‐saving, and environmentally friendly method for the further use of rigid shrimp shells and highly crystalline crustacean materials.

Graphene–Oxide Porous Biopolymer Hybrids Enhance In Vitro Osteogenic Differentiation and Promote Ectopic Osteogenesis In Vivo

“…XRD spectra revealed that the addition of GO within the GCs matrix seems to cause alterations [ 2 ] within the unmodified samples spectrum, as the 11.7° peak associated with chitosan’s crystal I [ 93 ] and 21° band paired to the crystal II structure [ 94 ] significantly sharpen. Hence, it can be assumed that the identified sharpening is associated with a higher degree of crystallinity of the polysaccharide [ 95 ]; crystallization firstly occurred after crosslinking and accelerated with the GO embedding [ 30 ] within the matrix. This is confirmed by the crystallinity index (CI) that resulted from CI = [(I cr − I am )/I110] × 100, where I cr is the maximum intensity of the diffraction peak of Cs, and I am is the intensity of amorphous diffraction at 2θ = 16° [ 96 ].…”

Nanosystems for the Encapsulation of Natural Products: The Case of Chitosan Biopolymer as a Matrix

“…Cheng et al [ 70 ] reported physicochemical properties of chitosan prepared by microwave and water bath heating with an equivalent quantity of heat intake. Briefly, chitosan production with microwave heating reduced the time of deacetylation from 180 to 60 min to reach the same DD% as the water bath heating with the same quantity of heat.…”

Microwave-assisted methacrylation of chitosan for 3D printable hydrogels in tissue engineering

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