scholarly journals Fiber-Templated 3D Calcium-Phosphate Scaffolds for Biomedical Applications: The Role of the Thermal Treatment Ambient on Physico-Chemical Properties

Materials ◽  
2021 ◽  
Vol 14 (9) ◽  
pp. 2198
Author(s):  
Aura-Cătălina Mocanu ◽  
Florin Miculescu ◽  
George E. Stan ◽  
Andreea-Mădălina Pandele ◽  
Mihai Alin Pop ◽  
...  
Keyword(s):  
Biomedical Applications ◽  
Mechanical Performance ◽  
Chemical Properties ◽  
Performance Assessments ◽  
Mechanical Reinforcement ◽  
Architectural Features ◽  
Fast Bone ◽  
Physico Chemical ◽  
Mechanical Performances

A successful bone-graft-controlled healing entails the development of novel products with tunable compositional and architectural features and mechanical performances and is, thereby, able to accommodate fast bone in-growth and remodeling. To this effect, graphene nanoplatelets and Luffa-fibers were chosen as mechanical reinforcement phase and sacrificial template, respectively, and incorporated into a hydroxyapatite and brushite matrix derived by marble conversion with the help of a reproducible technology. The bio-products, framed by a one-stage-addition polymer-free fabrication route, were thoroughly physico-chemically investigated (by XRD, FTIR spectroscopy, SEM, and nano-computed tomography analysis, as well as surface energy measurements and mechanical performance assessments) after sintering in air or nitrogen ambient. The experiments exposed that the coupling of a nitrogen ambient with the graphene admixing triggers, in both compact and porous samples, important structural (i.e., decomposition of β-Ca3(PO4)2 into α-Ca3(PO4)2 and α-Ca2P2O7) and morphological modifications. Certain restrictions and benefits were outlined with respect to the spatial porosity and global mechanical features of the derived bone scaffolds. Specifically, in nitrogen ambient, the graphene amount should be set to a maximum 0.25 wt.% in the case of compact products, while for the porous ones, significantly augmented compressive strengths were revealed at all graphene amounts. The sintering ambient or the graphene addition did not interfere with the Luffa ability to generate 3D-channels-arrays at high temperatures. It can be concluded that both Luffa and graphene agents act as adjuvants under nitrogen ambient, and that their incorporation-ratio can be modulated to favorably fit certain foreseeable biomedical applications.

scholarly journals How to Improve Physico-Chemical Properties of Silk Fibroin Materials for Biomedical Applications?—Blending and Cross-Linking of Silk Fibroin—A Review

Materials ◽  
2021 ◽  
Vol 14 (6) ◽  
pp. 1510
Author(s):  
Sylwia Grabska-Zielińska ◽  
Alina Sionkowska
Keyword(s):  
Silk Fibroin ◽  
Biomedical Applications ◽  
Magnetic Particles ◽  
Chemical Properties ◽  
Ternary Mixtures ◽  
Cross Linking ◽  
Advantages And Disadvantages ◽  
Physico Chemical ◽  
Binary And Ternary Mixtures ◽  
To Receive

This review supplies a report on fresh advances in the field of silk fibroin (SF) biopolymer and its blends with biopolymers as new biomaterials. The review also includes a subsection about silk fibroin mixtures with synthetic polymers. Silk fibroin is commonly used to receive biomaterials. However, the materials based on pure polymer present low mechanical parameters, and high enzymatic degradation rate. These properties can be problematic for tissue engineering applications. An increased interest in two- and three-component mixtures and chemically cross-linked materials has been observed due to their improved physico-chemical properties. These materials can be attractive and desirable for both academic, and, industrial attention because they expose improvements in properties required in the biomedical field. The structure, forms, methods of preparation, and some physico-chemical properties of silk fibroin are discussed in this review. Detailed examples are also given from scientific reports and practical experiments. The most common biopolymers: collagen (Coll), chitosan (CTS), alginate (AL), and hyaluronic acid (HA) are discussed as components of silk fibroin-based mixtures. Examples of binary and ternary mixtures, composites with the addition of magnetic particles, hydroxyapatite or titanium dioxide are also included and given. Additionally, the advantages and disadvantages of chemical, physical, and enzymatic cross-linking were demonstrated.

scholarly journals Occurrence of drug target residues within decantation tank sediments: a good clue to assess their historical excretion?

2021 ◽  
Vol 31 (1) ◽  
Author(s):  
Thomas Thiebault ◽  
Laëtitia Fougère ◽  
Anaëlle Simonneau ◽  
Emilie Destandau ◽  
Claude Le Milbeau ◽  
...  
Keyword(s):  
Drug Target ◽  
Chemical Properties ◽  
Deposition Process ◽  
Drug Consumption ◽  
Organic Layers ◽  
Sewer Systems ◽  
Physico Chemical ◽  
Deep Underground ◽  
Deposition Processes

AbstractThis study investigated the potential of sediments accumulated in sewer systems to record human activities through the occurrence of drug target residues (DTR). The installation studied is 17 m deep underground decantation tank that traps the coarse fractions of a unitary sewer system (northern part of Orléans, France), collecting both stormwater and wastewater. The sediments deposited in this tank could constitute a nonesuch opportunity to study the historical evolution of illicit and licit drug consumption in the catchment, however, the deposition processes and the record of DTRs remain largely unknown at present. Five cores were acquired from 2015 to 2017. One hundred fifty-two sediment samples were extracted using a mixture of ultra-pure water:methanol (1:1) prior to analysis of the extracts by high-pressure liquid chromatography coupled to tandem mass spectrometry. Several classical sedimentological analyses such as total organic carbon, facies description and granulometry were also performed on these samples, in order to understand the most important factors (e.g., physico-chemical properties of the DTRs, solid type, assumed load in wastewater) impacting their deposition.The key role of the speciation of DTRs was highlighted by the higher contents in neutral and anionic DTRs in organic layers, whereas only cationic DTRs were found in mineral layers. The considerable modifications in the sediments’ properties, generated by distinct origins (i.e., stormwater or wastewater), are therefore the most important drivers that must be taken into account when back-calculating the historical patterns of drug consumption from their DTR concentrations in decantation tank sediments. Further research remains necessary to fully understand the deposition process, but this study provides new clues explaining these temporal evolutions.

scholarly journals Impact of Quantum Dot Surface on Complex Formation with Chlorin e6 and Photodynamic Therapy

Nanomaterials ◽  
2018 ◽  
Vol 9 (1) ◽  
pp. 9 ◽  
Author(s):  
Artiom Skripka ◽  
Dominyka Dapkute ◽  
Jurga Valanciunaite ◽  
Vitalijus Karabanovas ◽  
Ricardas Rotomskis
Keyword(s):  
Photodynamic Therapy ◽  
Cancer Therapy ◽  
Complex Formation ◽  
Chemical Properties ◽  
Disease Diagnosis ◽  
Chlorin E6 ◽  
Deep Tissue ◽  
Physico Chemical

Nanomaterials have permeated various fields of scientific research, including that of biomedicine, as alternatives for disease diagnosis and therapy. Among different structures, quantum dots (QDs) have distinctive physico-chemical properties sought after in cancer research and eradication. Within the context of cancer therapy, QDs serve the role of transporters and energy donors to photodynamic therapy (PDT) drugs, extending the applicability and efficiency of classic PDT. In contrast to conventional PDT agents, QDs’ surface can be designed to promote cellular targeting and internalization, while their spectral properties enable better light harvesting and deep-tissue use. Here, we investigate the possibility of complex formation between different amphiphilic coating bearing QDs and photosensitizer chlorin e6 (Ce6). We show that complex formation dynamics are dependent on the type of coating—phospholipids or amphiphilic polymers—as well as on the surface charge of QDs. Förster’s resonant energy transfer occurred in every complex studied, confirming the possibility of indirect Ce6 excitation. Nonetheless, in vitro PDT activity was restricted only to negative charge bearing QD-Ce6 complexes, correlating with better accumulation in cancer cells. Overall, these findings help to better design such and similar complexes, as gained insights can be straightforwardly translated to other types of nanostructures—expanding the palette of possible therapeutic agents for cancer therapy.

Retarding Bioactivity Effect of Ciprofloxacin Incorporated in Polyvinyl Alcohol/Bioglass Scaffold as Bone Graft

2015 ◽  
Vol 1104 ◽  
pp. 163-167 ◽  
Author(s):  
Salha Boulila ◽  
Hassane Oudadesse ◽  
Bertrand Lefeuvre ◽  
Khansa Chaabouni ◽  
Fatima Makni-Ayedi ◽  
...  
Keyword(s):  
Polyvinyl Alcohol ◽  
Biomedical Applications ◽  
Potential Role ◽  
Icp Oes ◽  
Rapid Reduction ◽  
Physico Chemical ◽  
Before And After ◽  
Osteoinductive Property ◽  
Apatitic Phase

The biomaterials are used for many biomedical applications. The main objective of the present work was to investigate the potential role of Bioglass (Melting)- Polyvinyl alcohol (BG (M)-PVA) and Bioglass (Melting)-Polyvinyl alcohol-20%Ciprofloxacin (BG (M)-PVA-20Cip) in regenerative bone capacity. These composites were implanted in the femoral condyles of Wistar rats and compared to that of ovariectomised groups. Our results noted, after the different period of implantation (15, 30, 60 and 90 days), that the Alkaline phosphatase (ALP) and Acid phosphatase (ACP) activities showed an excellent osteoinductive property of BG (M)-PVA, that this phenomena decreased with the presence of ciprofloxacin. Physico-chemical techniques (ICP-OES and SEM) were engaged to highlight the influence of antibiotic on the structure, porosity and bioactivity of a porous Glass-PVA before and after implantation. The results obtained by ICP-OES showed a rapid reduction in silicon (Si) and sodium (Na), and noted an accelerator increase in calcium (Ca) and phosphorus (P) ion concentrations in BG (M)-PVA that the BG (M)-PVA-20Cip. This result is confirmed by SEM. We can conclude that the loading of ciprofloxacin in BG (M)-PVA is characterized by a retard effect of formation of apatitic phase.

scholarly journals Influence of Dispersing Method on the Quality of Nano-Admixtures Homogenization in Cement Matrix

Materials ◽  
2020 ◽  
Vol 13 (21) ◽  
pp. 4865
Author(s):  
Elżbieta Horszczaruk ◽  
Paweł Łukowski ◽  
Cyprian Seul
Keyword(s):  
High Speed ◽  
Mechanical Performance ◽  
Chemical Properties ◽  
Cement Composite ◽  
Cement Matrix ◽  
Cement Composites ◽  
Nano Sio2 ◽  
Mechanical Stirring ◽  
Physico Chemical ◽  
Nano Fe3o4

In recent years, a nano-modification of the cement composites allowed to develop a number of new materials. The use of even small amount of nano-admixture makes possible not only to improve the physico-mechanical properties of the cement materials, but also to obtain the composite with high usability, optimised for the given application. The basic problem of nano-modification of the cement composites remains the effectiveness of dispersing the nanomaterials inside the cement matrix. This paper deals with the effect of the type and size of the nanoparticles on the tendency to their agglomeration in the cement matrix. The main techniques and methods of dispersing the nanomaterials are presented. It has been demonstrated, on the basis of the results of testing of three nanomodifiers of 0D type (nano-SiO2, nano-Fe3O4 and nano-Pb3O4), how the structure and properties of the nanomaterial affect the behaviour of the particles when dissolving in the mixing water and applying a superplasticiser. The nanoparticles had similar size of about 100 nm but different physico-chemical properties. The methods of dispersing covered the use of high-speed mechanical stirring and ultrasonication. The influence of the method of nano-modifier dispersing on the mechanical performance of the cement composite has been presented on the basis of the results of testing the cement mortars modified with 3% admixture of nano-SiO2.

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