Hierarchical structure and biomineralization in cricket tooth

TL;DR

This study investigates the hierarchical structure and biomineralization process in cricket teeth, revealing zinc-based crystalline compounds and nanoscale microfibril organization that contribute to their sharpness and strength.

Contribution

It provides detailed insights into the elemental composition, crystalline structures, and hierarchical organization of cricket teeth, highlighting biomineralization mechanisms.

Findings

Zinc is the main heavy element in cricket teeth.

Surface contains ZnFe2(AsO4)2(OH)2(H2O)4 crystalline compound.

Interior contains ZnCl2-like biomineral forming nanoscale microfibrils.

Abstract

Cricket is a truculent insect with stiff and sharp teeth as a fighting weapon. The structure and possible biomineralization of the cricket teeth are always interested. Synchrotron radiation X-ray fluorescence, X-ray diffraction and small angle X-ray scattering techniques were used to probe the element distribution, possible crystalline structures and size distribution of scatterers in cricket teeth. Scanning electron microscope was used to observe the nanoscaled structure. The results demonstrate that Zn is the main heavy element in cricket teeth. The surface of the cricket teeth has a crystalline compound like ZnFe2(AsO4)2(OH)2(H2O)4. While, the interior of the teeth has a crystalline compound like ZnCl2, which is from the biomineralization. The ZnCl2-like biomineral forms nanoscaled microfibrils and their axial direction points at the top of tooth cusp. The microfibrils aggregate random into intermediate filaments, forming a hierarchical structure. A sketch map of the cricket tooth cusp was proposed and a detailed discussion was given in this paper.