The SEM and TEM study on the structure of organic scaffold (conchix) isolated from Mytilus edulis L. mussel shells

¹ Murmansk Arctic University, 183010 Murmansk, Russia
² Kazan Institute of Biochemistry and Biophysics, FRC Kazan Scientific Center of RAS, 420111 Kazan, Russia

^* Corresponding author: derkachsr@mstu.edu.ru

Abstract

Demineralised shell of marine molluscs represents an scaffold matrix or conchix and a promising mineral-free biomaterial. The purpose of this work was to study the microstructure of the demineralized shell of the mussel Mytilus edulis L. – an organic matrix isolated with various decalcified reagents – a solution hydrochloric acid HCl and a solution of ethylenediaminetetraacetic acid disodium salt Na₂-EDTA. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) were used as experimental methods in this study. It is shown that the chemical nature of the demineralising reagent determines the structural features of the studied conchix samples, their three layers – periostracum, prismatic layer and nacreous layer in particular. Treatment of mussel shells with HCl solution to remove calcium carbonate leads to partial destruction of the biopolymer structure of the binding organic matrix of mussel shells. Gentle treatment of mussel shells with EDTA solution ensures the preservation of the native structure of the organic matrix. This mineral-free biopolymer has high potential for using in food industry and biomedical applications.