A series of Zinc and Silver co-substituted Sr5(PO4)2SiO4 samples were developed to evaluate the induction of antibacterial properties within the parent material. Structural evaluation of the powder ...samples showed a good agreement of diffraction data with respective ICDD data cards, and biocompatible secondary phases were found to be present alongside the parent material. A decrease in crystallite size (<40 nm) was observed as the substitution level increased calculated from Scherrer's equation which was also evident in infrared spectra. 6% molar substitution (Zn-3% & Ag-3%) was found to be optimized concentration for the same based on biocompatibility studies involving Hemolytic and MTT assay against MG-63 cell lines. The samples were identical in morphology to Hydroxyapatite and showed excellent bone regeneration capabilities supported by secondary phases confirmed during SBF treatment studies evaluated using diffraction, IR spectra, and electron microscopy that showed signs of apatite seeding over the particles. Both Qualitative and quantitative antibacterial tests in the form of Media poisoning and CFU calculations proved successful acquisition of antibacterial properties at 6% molar substitution. Hence the proposed system can be deemed antibacterial and biocompatible for human application and further evaluated as a possible substitute for Ca–P ceramics for bone regeneration applications.
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•Zinc substitution was successfully achieved in Strontium Phosphosilicate.•Needle morphology of P63/m was observed to be retained with Zinc Substitution.•Optimised substitution levels ...were decided based on biocompatibility studies.•Antibacterial efficacy of parent material increased with respective levels of doping.•Apatite seeding was discovered in vitro that ultimately leads to bone mineralization.
Synthesis of Pure phase and a series of Zinc substituted Strontium phosphosilicate was attempted in the present study and assessed structurally and biologically. The Sol-Gel technique ensured proper reactivity and apatite formation upon sintering. The acidic medium was more applicable for synthesis on account of the isoelectric point of silica and formation of secondary Sr2SiO4 phase, important and applicable in bioactivity apart from Sr2P2O7 as another secondary phase. Sintering formed agglomerated stable crystalline phases evident from diffraction further confirmed by infrared spectroscopy. The morphology showed minimal differences from the parent material increasing agglomeration upon the increment of dopant. Biological evaluations showed the successful formation of amorphous Calcium phosphate with two days of SBF immersion and proliferation of MG-63 Cells upon Zinc incorporation. The antibacterial properties were enhanced upon the incorporation of Zinc while Strontium phosphosilicate in the pure phase failed to produce favourable antibacterial activity.
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•HAP composite coatings with 0–5% of f-MWCNTs on 316 L SS were prepared by ELD method•Contact angle studies showed better hydrophobicity for the 5% HAP/f-MWCNTs coating•Tafel and EIS ...plots of composite coatings exhibited enhanced corrosion resistance•HAP/f-MWCNTs composite coated 316 L SS showed improved Vickers hardness (Hv)
Coatings using functionalized multi-walled carbon nanotubes (f-MWCNTs)/hydroxyapatite (HAP) on 316 L Stainless Steel by electrodeposition at the parameter of “-1.5 V” for 30 min. with three electrode set-up configuration and optimization of various concentrations of f-MWCNTs from 1 to 5% were done to improve the coating characteristics for future biomedical applications. The obtained coatings were characterized by Fourier Transformed-Infra Red spectroscopy (FT-IR) and X-ray diffractometer (XRD) to reveal the phase formation in the composites. With various additions of f-MWCNTs, the HAP phase was found to be retained. The growth of HAP on f-MWCNTs was analyzed by High-resolution Transmission Electron Microscope (HR-TEM) and the morphology of composite was found to be of the needle and flower-like particles. To understand the corrosion resistance effect of the developed HAP/f-MWCNTs composite in SBF, electrochemical investigations were carried out using Impedance and Tafel polarization analysis. From the results, it was observed that the coatings have enhanced corrosion resistance behavior and bioactivity. In addition, the Vickers Hardness study proved that the prepared HAP/fMWCNTs composite coating was found to have improved hardness value of (Hv) 390.2 ± 8.0. Thus, the electrodeposited composite coating on 316 L SS substrate can be effectively deployed for biomedical applications.
Mycoremediation is deemed as a very effective method of pollutant removal considering the versatility of fungi in terms of their ecology, nutritional modes, adaptability, morphology, physiology, and ...metabolism. Fungi, being decomposers, are indispensable for nutrient recycling in an ecosystem. They have the unique ability to metabolize different organic and inorganic pollutants using them as energy and carbon sources, and degrading them to innocuous concentrations and non-hazardous states. A large number of fungal genera from almost all fungal phyla have exhibited the ability of pollutant degradation, while two major phyla Basidiomycota and Ascomycota have been most extensively explored due to their profound ligninolytic activities and thereby remarkable mycoremediation performance. Biodegradation of a large number of pollutants has been accomplished using fungal systems, such as polyaromatic hydrocarbons, pharmaceutically active compounds, heavy metals, synthetic dyes, toxins, and radionuclides. These pollutants are degraded through physically or enzymatically controlled mechanisms like bioaccumulation, biosorption, biomineralization, and biotransformation. This review widely focuses on the exploration of fungal diversity for bioremediation of different types of pollutants encompassing their physiological aspects. It also unravels the mechanisms involved in the pollutant degradation processes and gives an insight into the strategies that could enhance the efficiency of mycoremediation process.
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•Silica nanoparticles have been reported in green manner.•A feasibility of producing pure silica from waste materials by alkali/acid treatment.•Acidic extraction, high purity 98% has ...been obtained.•Ash obtained from waster materials would be promising low cost raw material.
The major interest of the paper deals with the extraction of silica from four natural sources such as rice husk, bamboo leaves, sugarcane bagasse and groundnut shell. These waste materials in large quantities can create a serious environmental problem. Hence, there is a need to adopt proper strategy to reduce the waste. In the present investigation, all the waste materials are subjected to moisture removal in a hot plate and sintered at 900°C for 7h. The sintered powder was treated with 1M NaOH to form sodium silicate and then with 6M H2SO4 to precipitate silica. The prepared silica powders were characterized by FT-IR, XRD and SEM-EDAX analysis. The silica recovered from different sources was found to vary between 52% and 78%. Magnesium substituted silica was formed from the groundnut waste and further treatment is required to precipitate silica.
The purpose of this study is to prepare and evaluate the effect of synthesized titanium dioxide (TiO2) nanoparticles for their biocompatibility on physiological body fluids and the effect of cell ...toxicity to produce osteointegration when used as implantable materials. For the past few decades, the number of researches done to understand the importance of the biocompatibility of bioceramics, metals, and polymers and their effect on clinical settings of biomedical devices has increased. Hence, the total concept of biocompatibility encourages researchers to actively engage in the investigation of the most compatible materials in living systems by analyzing them using suitable physical, chemical, and biological (bioassay) methods. The ceramic material nano TiO2 was prepared by sol-gel method and analyzed for its functional group and phase formation by Fourier transform infrared spectroscopy and powder X-ray diffraction. Furthermore, the particle size, shape, surface topography, and morphological behavior were analyzed by dynamic light scattering, zeta potential, scanning electron microscopy-energy dispersive X-ray analysis, and transmission electron microscopy analysis. In addition to this, the cytotoxicity and cytocompatibility were determined on MG63 cell lines with varying doses of concentrations such as 1 µg/mL, 10 µg/mL, 25 µg/mL, 50 µg/mL, and 100 µg/mL with different time periods such as 24 hours and 48 hours. The results have not shown any toxicity, whereas, it improved the cell viability/proliferation at various concentrations. Hence, these findings indicate that the nano TiO2 material acts as a good implantable material when used in the biomedical field as a prime surface-modifying agent.
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•We have synthesized the HAP with inclusion of Ce4+ and Si4+ by Sol-Gel method.•XPS analysis proves the valence states of Ce and Si ions as 4+ in HAP.•Ce/Si-HAP shows the excellent ...blood compatible, anti-microbial and apatite formation.•Ce/Si-HAP@5% exhibits the good cellular metabolic activity towards MG-63 osteoblast.
Multi-ion, co-substituted bioactive glass ceramics play a significant role in the stimulation of physical and biological properties for outstanding effects in biomedical application. The following work attempts to develop HAP as a parent material doped with a combination of cerium (Ce4+ @1.25 wt%) and silicon (Si4+ @1, 3 and 5 wt%) by refluxing based sol-gel technique. The anti-bacterial tests exhibit E. coli showing higher inhibition efficiency, in vitro hemolytic test exhibit good compatible nature of dual doped HAP with erythrocytes (<5% of hemolytic). In vitro bioactivity assay confirms that the developed dual doped HAP possesses excellent bone-like apatite layer formation on their surfaces. In vitro cellular study was performed for Ce/Si-HAP@5% powder against MG-63 cells, which demonstrated the good cell viability at higher concentrations (up to 800 µg/ml). Further, dual doped HAP powders were characterized by various analytical techniques such as ATR-FTIR, Powder-XRD, TGA-DTA, SEM-EDS, TEM and XPS analysis. The studies confirm that the synthesized dual doped HAP will act as better bioactive glass ceramics for potential orthopedic and dentistry applications.
Human osteology is the biomechanics science that deals with the study of minerals and non-collagenous organic components that shield human organs and aids in the production of blood cells. A bone ...follows a specific regenerative pattern after injury or defect. Direct healing ability is still a substantial medical challenge in pathological or nonunion conditions. Such bone defects often necessitate a choice of biomaterial matrix (polymer/ceramic/bioglasses/metallic implants) with the combinations of bioactive signaling molecules (drug molecules) in a spatiotemporal pattern. In this regard, we address the development of a drug delivery system and also outline the interactions of drug molecules with the scaffolding surface that could further trigger the regeneration process. Eventually, the review highlights the notion of drug embedded onto the three-dimensional scaffolds and the release profiles surface coated metallic implant that creates a new window for bone tissue engineering. Besides, a systematic review was performed for literature regarding the role of antibiotics and dual drug delivery strategies that would have a potential utilization of bone-related infection control.
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Most high load-bearing implants are metallic alloys which contain toxic chemical components that might be released due to the corrosive environment of body fluids and load-bearing activity. Surface ...modification techniques do not guarantee biocompatibility. Hence, the bioactive surface of implants can be modified by coating the surface with a suitable material that addresses the needs of the patient. The choice and application process of the coatings should be determined based on the workability of the material and its physiochemical properties, such as the procedures involved and performance in avoiding removal of any desirable material properties that are helpful in the tissue regeneration process. Tailor-made coating materials prove very promising, as they might improve permanent implantations, make them more affordable and reduce the need for surgical revisions. The scope of the featured properties, such as addition of accelerated tissue regeneration, antibacterial properties and controlled release and removal of debris from the biological system to the metal implants makes coatings an ideal choice for surface modification of implants. This report reviews several options available for forming a biologically active layer over metallic surfaces that will interact with and produce desirable effects on host tissues.
In this study, for the first time we have developed the composite coatings using sol-gel derived hydroxyapatite HAP: (Ca)10(PO4)6(OH)2 and magnetite (Fe3O4) on alkali treated Ti-6Al-4V alloy using ...various concentrations of Fe3O4 nanoparticles such as 1, 3 and 5wt% respectively. The fabricated composite coatings were characterized by XRD, SEM-EDAX and contact angle measurements. In vitro bioactivity study confirmed that the composite coated Ti-6Al-4V was highly bioactive and induces bone like apatite formation in the presence of Fe3O4 NPs which involves the nucleus formation by developing Fe-OH groups on the surface of coatings. The corrosion resistance study proved that 1wt% of Fe3O4 with HAP composite coatings exhibit good anticorrosion behaviour than the 3, 5wt% of composites due to lower Fe-OH groups and uniform with adherent layer which restricts the leaching of ions. Hence, this finding suggested that HAP/Fe3O4 composites coated implants can be used for biomedical applications.
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•First time, we have developed HAP-Fe3O4 coatings on Ti-6Al-4V by spin coating.•Petal to needle shaped morphology was observed with increase in Fe3O4 content.•Ball like apatite crystals were formed due to electrostatic interaction of Fe-OH.•Corrosion resistance was more for 1wt% of Fe3O4 due to less Fe-OH groups leaching.
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