The State of Starch/Hydroxyapatite Composite Scaffold in Bone Tissue Engineering with Consideration for Dielectric Measurement as an Alternative Characterization Technique.

Mohd Riza Mohd Roslan,Ee Meng Cheng,Joo Shun Tan,Nadhiya Liyana Mohd Kamal,Chong You Beh,Nashrul Fazli Mohd Nasir,Mohd Shamzi Mohamed,Muhammad Farid Abdul Khalid

doi:10.3390/ma14081960

Abstract

Hydroxyapatite (HA) has been widely used as a scaffold in tissue engineering. HA possesses high mechanical stress and exhibits particularly excellent biocompatibility owing to its similarity to natural bone. Nonetheless, this ceramic scaffold has limited applications due to its apparent brittleness. Therefore, this had presented some difficulties when shaping implants out of HA and for sustaining a high mechanical load. Fortunately, these drawbacks can be improved by combining HA with other biomaterials. Starch was heavily considered for biomedical device applications in favor of its low cost, wide availability, and biocompatibility properties that complement HA. This review provides an insight into starch/HA composites used in the fabrication of bone tissue scaffolds and numerous factors that influence the scaffold properties. Moreover, an alternative characterization of scaffolds via dielectric and free space measurement as a potential contactless and nondestructive measurement method is also highlighted.

Highlights

Tissue engineering revolves around exploiting biological and engineering fundamentals to collocate cells and scaffold materials in assisting tissue growth and recovery process.It is favorably viewed as a feasible method to overcome transplantation issues due to inadequacies alluded to donor tissues or organs [1]
In the latest study by Beh et al [51], the scaffold made of corn starch and nanohydroxyapatite (n-HA) composite has a network of macropores (200–600 μm) and micropores
The factors that improve the properties of a scaffold, in terms of its structure, including using a larger amount of starch, sintering at a lower temperature, and using heat-treated hydroxyapatite

Summary

Introduction

Tissue engineering revolves around exploiting biological and engineering fundamentals to collocate cells and scaffold materials in assisting tissue growth and recovery process. Hollister [19] underlined the significance of scaffold materials and porous structural designs that fall in the region of 10 μm to 100 μm to manifest temporary mechanical function, preserve tissue volume, and deliver necessary biofactors (stem cells, genes and proteins) for stimulating the tissue repair. In the latest study by Beh et al [51], the scaffold made of corn starch and nanohydroxyapatite (n-HA) composite has a network of macropores (200–600 μm) and micropores (50–100 μm) It has a high degree of interconnectivity, suggesting that highly porous cornstarch/HA endowed with good mechanical properties can be a potential biomaterial for bone tissue engineering applications. The scaffold must be designed to meet specific porosity requirements to facilitate cell attachment and migration, apart from having sufficient mechanical strength to support newly generated tissues These porosity requirements include the size of pores, the interconnectivity of pores, and distribution. Micropores size range from 622 μm to 966 μm, while macropores size range from 3683 μm to 5517 μm Little microporosity suggesting the scaffold is fully dense

Findings

Starch as Particulate Pore Former

The Effect of Porosity in Ceramic over Microwave Dielectric Measurement

Conclusions