Preparation of Laponite Bioceramics for Potential Bone Tissue Engineering Applications

Abstract

We report a facile approach to preparing laponite (LAP) bioceramics via sintering LAP powder compacts for bone tissue engineering applications. The sintering behavior and mechanical properties of LAP compacts under different temperatures, heating rates, and soaking times were investigated. We show that LAP bioceramic with a smooth and porous surface can be formed at 800°C with a heating rate of 5°C/h for 6 h under air. The formed LAP bioceramic was systematically characterized via different methods. Our results reveal that the LAP bioceramic possesses an excellent surface hydrophilicity and serum absorption capacity, and good cytocompatibility and hemocompatibility as demonstrated by resazurin reduction assay of rat mesenchymal stem cells (rMSCs) and hemolytic assay of pig red blood cells, respectively. The potential bone tissue engineering applicability of LAP bioceramic was explored by studying the surface mineralization behavior via soaking in simulated body fluid (SBF), as well as the surface cellular response of rMSCs. Our results suggest that LAP bioceramic is able to induce hydroxyapatite deposition on its surface when soaked in SBF and rMSCs can proliferate well on the LAP bioceramic surface. Most strikingly, alkaline phosphatase activity together with alizarin red staining results reveal that the produced LAP bioceramic is able to induce osteoblast differentiation of rMSCs in growth medium without any inducing factors. Finally, in vivo animal implantation, acute systemic toxicity test and hematoxylin and eosin (H&E)-staining data demonstrate that the prepared LAP bioceramic displays an excellent biosafety and is able to heal the bone defect. Findings from this study suggest that the developed LAP bioceramic holds a great promise for treating bone defects in bone tissue engineering.

LAPONITE® nanorods regulating degradability, acidic-alkaline microenvironment, apatite mineralization and MC3T3-E1 cells responses to poly(butylene succinate) based bio-nanocomposite scaffolds

“…LAP is silicate, thus the mechanism of apatite mineralization on the composites scaffolds might be similar to the apatite mineralization on silicate-based biomaterials in SBF (rich Si-OH rst formed on material surface in SBF, then induced Ca ion distribution, calcium phosphate nucleation, and ultimate apatite formation) as described in previous publications. 5 Cells adhesion and spreading on the biomaterial surface are the rst sequential reactions, which are crucial for subsequent cells proliferation and differentiation. 34 In this study, from the SEM micrographs, the MC3T3-E1 cells adhered and spread better on sPL30 than sPL15, and sPL15 better than sPL0 scaffolds.…”

“…3 Study has shown that LAP induced the osteogenic differentiation of the MC3T3-E1 cells by enhancing ALP activity, runt-related transcription factor 2 (RUNX2) transcript upregulation, bonerelated matrix protein deposition (osteocalcin and osteopontin), following by matrix mineralization. 4,5 In previous studies, LAP has been incorporated into electrospun poly(lactic-co-glycolic acid) nanobers scaffolds, which remarkably enhanced osteoblastic differentiation (alkaline phosphatase activity and osteocalcin secretion) of human mesenchymal stem cells (hMSCs). 3,6 In addition, nanocomposite hydrogel of cross-linked poly(ethylene oxide) and LAP with the content ranging from 40 to 70 wt% were prepared, which signicantly stimulated the adhesion, spreading, proliferation and differentiation of the MC3T3-E1 cells.…”

Comparative study of porous hydroxyapatite/chitosan and whitlockite/chitosan scaffolds for bone regeneration in calvarial defects

“…To avoid the disadvantages of tissue-based bone graft, synthetic biocompatible scaffolds have been applied in tissue engineering for bone regeneration. [3][4][5] Hydroxyapatite (HAP; Ca 10 (PO 4 ) 6 (OH) 2 ), a major inorganic component of biological hard tissues such as bone and tooth, has been widely investigated for its application in bone tissue engineering owing to its excellent biocompatibility and biodegradability. [6][7][8][9] For example, Bhumiratana et al 10 explored the incorporation of silk sponge matrices with HAP microparticles to generate highly osteogenic composite scaffolds, which could induce in vitro bone formation.…”

In vitroandin vivostudies of a gelatin/carboxymethyl chitosan/LAPONITE® composite scaffold for bone tissue engineering

“…22 Despite advances in the physical and chemical properties of polymers by reinforcement with nanoclay, few studies have examined the interaction between clay-based scaffolds and cells. [23][24][25][26] Ambre et al reported that incorporating synthetic silicate into chitosan/polygalacturonic acid scaffolds promoted osteogenic differentiation of human mesenchymal stem cells (hMSCs). 26 Hong Zhuang et al found out that montmorillonite-intercalated gelatin/chitosan induced the adhesion and proliferation of rat stromal stem cells; 27 Ganesh Nitya et al demonstrated hMSCs seeded on scaffolds embedded with halloysite nanoclay showed higher proliferation rate and alkaline phosphatase (ALP) activity.…”