Insight into morphological, physicochemical and spectroscopic properties of β-chitin nanocrystalline structures

William Marcondes Facchinatto; Danilo Martins Dos Santos; Andrea de Lacerda Bukzem; Tiago Bueno Moraes; Filipe Habitzreuter; Eduardo Ribeiro de Azevedo; Luiz Alberto Colnago; Sérgio Paulo Campana-Filho

doi:10.1016/j.carbpol.2021.118563

Insight into morphological, physicochemical and spectroscopic properties of β-chitin nanocrystalline structures

Carbohydr Polym. 2021 Dec 1:273:118563. doi: 10.1016/j.carbpol.2021.118563. Epub 2021 Aug 18.

Authors

William Marcondes Facchinatto¹, Danilo Martins Dos Santos², Andrea de Lacerda Bukzem³, Tiago Bueno Moraes⁴, Filipe Habitzreuter³, Eduardo Ribeiro de Azevedo⁵, Luiz Alberto Colnago², Sérgio Paulo Campana-Filho³

Affiliations

¹ São Carlos Institute of Chemistry, University of São Paulo, Avenida Trabalhador sao-carlense 400, Zip Code 13560-590, PO Box 780, São Carlos, SP, Brazil. Electronic address: williamfacchinatto@alumni.usp.br.
² Brazilian Corporation for Agricultural Research, Embrapa Instrumentation, Rua XV de Novembro 1452, Zip Code 13560-970, PO Box 741, São Carlos, SP, Brazil.
³ São Carlos Institute of Chemistry, University of São Paulo, Avenida Trabalhador sao-carlense 400, Zip Code 13560-590, PO Box 780, São Carlos, SP, Brazil.
⁴ Department of Chemistry, Institute of Exact Sciences, Federal University of Minas Gerais, Av. Antônio Carlos, 6627, Zip Code 31270-901, PO Box 702, Belo Horizonte, MG, Brazil.
⁵ São Carlos Institute of Physics, University of São Paulo, Avenida Trabalhador São-carlense 400, Zip Code 13560-590, PO Box 369, São Carlos, SP, Brazil.

PMID: 34560974
DOI: 10.1016/j.carbpol.2021.118563

Abstract

We systematically investigated the effect of β-chitin (BCH) particle size on the preparation of nanocrystals/nanowhiskers (CWH) by acid hydrolysis. Regardless this variable, CWH aqueous suspension exhibited outstanding stability and the average degree of acetylation remained nearly constant after the acid treatment. In contrast, the morphology, dimensions, crystallinity, and molecular weight of CHW were significantly affect by the particle size. Although needle-like crystals have predominated, BCH particles sizes significantly affected the dimensions and asymmetry of CWH, as confirmed by the rheological and NMR relaxation (T₂) behaviors. According to different SSNMR approaches, the acid hydrolysis meaningless affected the local chain conformation, while the spatial freedom of BCH intersheets, rated upon the mobility of methyl segments, was taken as evidence of higher permeability of acid into small particle sizes. Thus, this study demonstrated the importance of standardizing the surface/bulk proportions of β-chitin aiming to predict and control the CWH morphology and related properties.

Keywords: Beta-Chitin Nanocrystals; Beta-Chitin Nanowhiskers; Morphology; Particle surface/bulk proportions relationship; Rheological behavior; SSNMR spectroscopy.