Micro-computed tomography (Micro-CT) analysis in assessing the pore structure of hydroxyapatite-functionalized bacterial cellulose for bone tissue engineering

Abstract

The porous structure of scaffolds is critical in facilitating cellular activities such as mass transport, cell migration, and vascularization. The pore size and porosity of the scaffold need to be adjusted according to the specific tissue to enable long-term cultivation in vitro. Therefore, selecting the method to be used in the porosity characterization is critical. In addition to analyzing pore characteristics, micro-computed tomography (Micro-CT) can assess parameters such as the degree of anisotropy, interconnectivity, and hydroxyapatite (HAp) density in bone tissue scaffolds, providing advantages over alternative methods. In this study, a bacterial cellulose-HAp scaffold was fabricated, and its porosity, pore distribution, wall thickness distribution, surface area, degree of anisotropy, and HAp density were characterized. Additionally, 3D models of the scaffold were generated using Micro-CT imaging. The findings of this study demonstrate that Micro-CT is an effective tool for measuring these critical parameters in soft, foam, or flexible scaffolds without causing structural damage. The advantages of this technique over alternative methods are also emphasized. Upon examining the Micro-CT results of the scaffolds designed for bone tissue engineering, it was found that the pore sizes predominantly ranged from 90 to 150 μm, with a maximum pore size of 320 μm. The porosity was approximately 85%, the degree of anisotropy was 1.06, and the HAp density was 125 mg/cm³. It was concluded that these parameters are suitable for bone formation, indicating that the produced scaffolds are suitable for bone tissue engineering.