Carbon nanotubes in nanocomposites and hybrids with hydroxyapatite for bone replacements (original) (raw)
Related papers
2021
The reassessment of the literature stipulates that an increasing amount of research in exploring the Hydroxyapatite Carbon Nanotubes (HA-CNT) system for orthopedic application. Chemical precipitation, CNT functionalization, and spray drying are the routinely used methods for CNT dispersal in HA matrix for the application such as bone tissue engineering, nanostructured scaffolds, dental regeneration, myocardial regeneration, and skin regeneration. Although mechanical strength and biocompatibility is a substantial concern for the fabrication of structures. Developing composite and bioceramic scaffolding with different natural and synthetic biomaterials are the futuristic approach in the biomedical engineering field. The problems such as biocompatibility, biodegradability, and mechanical resistance can be solved by combining natural, and artificial biomaterials. The natural biomaterials, such as collagen, cellulose, chitosan, have a close resemblance to the natural extracellular matrix...
Carbon nanotube reinforced hydroxyapatite composite for orthopedic application: A review
2012
Application of hydroxyapatite (HA) in orthopedic implants suffers from its low fracture toughness and poor wear resistance. Carbon nanotube (CNT), with its high stiffness and mechanical strength, is an attractive reinforcement for HA to surmount these issues. The last 7-8 years have seen a number of studies to explore the efficiency of CNT reinforcement in strengthening HA, in the form of composites and coatings. Impressive improvement in the fracture toughness and wear resistance of HA with CNT reinforcement and beneficial effects on biocompatibility has sparked further research interests, for possible clinical applications. This review article aims to cover a wide span of this exciting and expanding research arenafrom detailed technical discussions on HA-CNT system, their processing techniques and the influence of CNT dispersion in the HA matrix. Role of CNT in the improvement of mechanical properties and tribological behavior of the composite has been discussed in light of different processing techniques. Other important issues related to HA-CNT system, e.g., phase transformation and crystallinity of HA and HA-CNT interfacial bonding has been stressed upon. Biocompatibility of HA-CNT composites, which is extremely important for its intended orthopedic application, has been summarized with an overview of the present status. An in-depth analysis of the information presented in this review facilitates a better understanding of the current state of HA-CNT research and allows framing guidelines toward future research direction for its successful clinical application.
Journal of Ceramic Processing Research, 2021
Due to the predominance diseases such as bone fracture, bone cancer, and osteoporosis Worldwide. There is a developing requirement for synthesizing biomaterials for bone repair or substitute due to the predominance of bone fracture, bone cancer, and osteoporosis. In this study, multi-wall carbon nanotubes (MWCNT) of (0.6%, 1%, 1.4%, 2%) wt.% and High-density polyethylene HDPE (60) wt.% were incorporated into hydroxyapatite (40) wt.% to form biocomposite using hot-press techniques. These samples were characterized by XRD, Field Emission scanning electron microscope (FESEM), Atomic force microscopy (AFM), mechanical properties with tensile strength and hardness test. Homogeneous, better distribution of the fibrous network and microstructure arrangements were among the most prominent characteristics obtained through XRD, FESEM, and AFM examinations. The result showed improved approximately (3.1 times) compared with pure sample (without addition MWCNT) in the tensile test. Also, the microhardness improves approximate 24% compared to pure samples HA/ HDPE. Based on the experimental results, the synthesis HA/ HDPE/MWCNT bio-composites prepared to have excellent characteristics that make them suitable application as a substitute material for bone repair.
The present work describes a simple shear mixing technique for developing a hydroxyapatite (HAp)-carbon nanotube (CNT) nanocomposite and the effect of reinforcement on the physical, mechanical, in vitro bioactivity and biological properties of HAp. XRD and FTIR confirmed that the main phase of the composites is HAp. HRTEM images demonstrated the formation of a two-dimensional nanocomposite structure, whereas FESEM images indicated the formation of nanosized HAp grains featuring sporadically distributed CNT molecules. No major phase changes in HAp were observed with up to 5% added CNT. However, adding more than 1% CNTs caused an increase in internal crystal strain and increased substitution of CO 3 2 À for OH À and PO 4 3 À groups in pure HAp. The average crystallite size increased from $ 46 nm to 100nmwithonly0.5100 nm with only 0.5% added CNT, remained nearly unaffected up to 2% CNTs thereafter and suddenly decreased at 5% CNTs ( 100nmwithonly0.561 nm). The FESEM and HRTEM images clearly showed the attachment of MWCNT chains on HAp grains, which directly affected the samples' fracture toughness and flexural strength. Of the samples, 1% showed maximum values of K 1C , whereas 5% showed maximum values of HV and three-point bending flexural strength. The in vitro bioactivity indicated increased apatite formation on the sample surface up to 1% CNTs after 24 weeks. However, adding 2% and 5% CNTs resulted in a manifold increase in apatite formation up to 12 weeks, after which dissolution increased up to 24 weeks, possibly due to increased substitution of CO 3 2 À for OH À and PO 4 3 À groups. This result is confirmed by the FTIR studies. For all added CNT contents, all samples exhibited high haemocompatibility. However, there was a compromise between the observed mechanical properties and in vitro bioactivity studied up to 24 weeks, and care must be taken before selecting any final application of the nanocomposites.
Materials Science and Engineering: C, 2018
Hydroxyapatite-functionalized multi-walled carbon nanotube (HA-fMWCNT) magnetic nanocomposite was successfully prepared using a novel slurry-compounding method. The prepared HA-fMWCNT nanocomposite with the addition of small amount (0.5 wt%) of fMWCNT exhibited much greater improvement in mechanical properties due to strong interfacial adhesion between acid-treated MWCNTs fillers and HA matrix, thus efficient stress transfer to nanotubes from the matrix. The nanocomposite exhibited excellent haemocompatibility. Fractographic analysis was performed in order to understand the fracture behavior and toughening mechanisms. The fracture mechanisms and micro-deformation were examined by studying the microstructure of arrested crack tips using field emission scanning electron microscopy (FESEM). The origination and formation of micro-cracks are the dominant fracture mechanisms and micro-deformation in the HA-fMWCNTs nanocomposite. The developed new method enables to the fabrication of magnetic HA-fMWCNTs nanocomposite with superior mechanical performance may be potential for application as high load-bearing bone implants in the biomedical field.
Assisted deposition of nano-hydroxyapatite onto exfoliated carbon nanotube oxide scaffolds
Nanoscale, 2015
Electrodeposited nano-hydroxyapatite (nHAp) is more similar to biological apatite in terms of microstructure and dimension than apatites prepared by other processes. Reinforcement with carbon nanotubes (CNTs) enhances its mechanical properties and increases adhesion of osteoblasts. Here, we carefully studied nHAp deposited onto vertically aligned multi-walled CNT (VAMWCNT) scaffolds by electrodeposition and soaking in a simulated body fluid (SBF). VAMWCNTs are porous biocompatible scaffolds with nanometric porosity and exceptional mechanical and chemical properties. The VAMWCNT films were prepared on a Ti substrate by a microwave plasma chemical vapour deposition method, and then oxidized and exfoliated by oxygen plasma etching (OPE) to produce graphene oxide (GO) at the VAMWCNT tips.
Materiali in tehnologije
In this investigation, multi-wall carbon nanotubes (MWCNT) with various percentages (0.6%, 1%, 1.4%, 2%) were combined into and High-density polyethylene HDPE (60) wt. % and hydroxyapatite (40) wt. % to form biocomposite using hot-press techniques. The surface topography by AFM images illustrates differences in the roughness of the sample's surface with different adding percentages of MWCNT. The DSC technique exhibits the effect of adding MWCNT in different percentages with the degree of crystallinity, which its effect on mechanical properties for samples. The in vitro bioactivity was investigated by immersion the samples in Ringer's solution as simulated body fluid (SBF) at (0, 3, 6, 9, 12) days (after immersing). The FE-SEM and EDx image explained the apatite layers formation on the sample's surface after 3 days immersed in Ringer solution. Based on XRD Technique, after immersion days in the Ringer solution, the crystallographic structure of hydroxyapatite is formed...