In Situ Precipitation of Cluster and Acicular Hydroxyapatite onto Porous Poly(γ-benzyl-l-glutamate) Microcarriers for Bone Tissue Engineering

Abstract

Bone tissue engineering scaffold based on microcarriers provides an effective approach for the repair of irregular bone defects. The implantation of microcarriers by injection can reduce surgical trauma and fill various irregular shaped bone defects. Microcarriers with porous structure and osteogenic properties have shown great potential in promoting the repair of bone defects. In this study, two kinds of hydroxyapatite/poly-(γbenzyl-L-glutamate) (HA/PBLG) microcarriers were constructed by emulsion/in situ precipitation method and their structures and properties were studied. First, PBLG porous microcarriers were prepared by an emulsion method. Surface carboxylation of PBLG microcarriers was performed to promote the deposition of HA on PBLG microcarriers. Next, the modified porous PBLG microcarriers were used as the matrix, combined with the in situ precipitation method; the cluster HA and acicular HA were precipitated onto the surface of porous microcarriers in the presence of ammonia water and tri(hydroxymethyl)aminomethane (Tris) solution, respectively. The micromorphology, composition, and element distribution of the two kinds of microcarriers were characterized by TEM, SEM, and AFM. Adipose stem cells (ADSCs) were cultured on the cluster HA/PBLG and acicular HA/PBLG microcarriers, respectively. ADSCs could grow and proliferate normally on both kinds of microcarriers wherein the acicular HA/PBLG microcarriers were more favorable for early cell adhesion and showed a beneficial effect on mineralization and osteogenic differentiation of ADSCs. Successful healing of a rabbit femur defect verified the bone regeneration ability of acicular HA/PBLG microcarriers.

Pearl-inspired graphene oxide-collagen microgel with multi-layer mineralization through microarray chips for bone defect repair

“…Nowadays, the hydroxyapatite (HAp), which is produced by biomimetic mineralization process using simulated body fluids (SBFs), has become the most popular bone substitute material attributing to the similarity in the inorganic component of human and animal bones, good biocompatibility, osteoconductivity, and osteoinductivity [ 4 , [14] , [15] , [16] ]. The crystalline structure and morphology of HAp play vital roles in mediating cellular behaviors [ [17] , [18] , [19] , [20] ]. For instance, the crystalline structure of HAp affects the release process of Ca and P ions, which regulate the cell fate [ 19 ].…”

“…For instance, the crystalline structure of HAp affects the release process of Ca and P ions, which regulate the cell fate [ 19 ]. The morphology of HAp can provide biophysical information for adjusting cell behaviors [ 18 ]. In addition, the roughness surfaces of HAp can facilitate cell adhesion and proliferation [ 20 ].…”

Adsorption of Inositol Phosphate on Hydroxyapatite Powder with High Specific Surface Area

“…Hydroxyapatite (Ca 10 (PO 4 ) 6 (OH) 2 ; HAp), the main component of human bones and teeth, is known as a bioceramic and is commonly used as an artificial bone and tooth root [ 1 , 2 ]. Artificial bones put to practical use in the medical field have various forms and shapes, such as granules [ 3 ], blocks [ 4 ], cylinders [ 5 ], porous bodies [ 6 ], and paste (cement) [ 7 , 8 , 9 ], and suitable ones are selected depending on the application.…”

The effect of enhanced bone marrow in conjunction with 3D-printed PLA-HA in the repair of critical-sized bone defects in a rabbit model

“…In recent decades, hydroxyapatite (HA; Ca5-[PO4]3] OH]) and beta-tricalcium phosphate (β-TCP; Ca3[PO4])2) have been widely applied to facilitate bone repair and regeneration in clinical settings due to their recognized biocompatibility and osteoconductivity (15,16). Previous studies have also shown that single-phase materials cannot perfectly meet the needs of BTE scaffolds (17).…”