Factor Affecting Geometry of TiO2 Nanotube Arrays (TNAs) in Aqueous and Organic Electrolyte

TiO2 nanotube arrays (TNA) have attracted scientific interest due to the combination of functional material properties with controllable nanostructure. Superior properties of TNA, including vectorial pathway of e− transport, minimized e− recombination, and high specific surface area render them as the most promising candidate for environment remediation, energy conversion and biocompatibility applications. The superior properties and efficacy of the TNA in various applications influenced by structural characteristics such as pore size, length and wall thickness. Therefore in this chapter the effect of various electrochemical parameters such as applied voltage, anodization time, electrolyte composition on the formation of controlled dimension of TNA in aqueous and organic electrolytes are reviewed

Localization of conductivity towards scalable and sustainable wearable electronics

Localized conductivity on fabrics is envisioned to make a shift in sustainable wearable electronics. Among the wearable electronics, localized conductivity has not been widely reported yet. Hence, we report a simple way to localize conductivity on polyester fabrics using reduced Graphene Oxide (rGO). Coupling agent, (3-aminopropyl) triethoxysilane (APTES) was used to change the chemically dormant nature of polyester fabrics, which made easy networking with GO. Then, the GO coating was substantially reduced to rGO, accomplishing conductive tracks on fabrics. rGO coated fabric showed a surface resistivity of 320 Ω/□. Even after 20 washing cycles, a significant change in surface resistivity was not observed which signifies a good wash fastness. APTES created a covalent bond network between rGO and polyester, which was proven by FTIR. This cost effective and sustainable method endows the electronic textile industry with a rapid improvement towards scalable production

Localised Delivery of Cisplatin from Chitosan-Coated Titania Nanotube Array Nanosystems Targeting Nasopharyngeal Carcinoma

Pupose: Cisplatin (CDDP), while amongst the recognised chemotherapeutic drugs currently available, is known to have limitations; the lack of a single treatment approach and non-specific targeted therapies. Therefore, the development of an innovative strategy that could achieve localised CDDP treatment is an urgent undertaking. Recent advances in titania nanotube arrays (TNAs) technology have demonstrated promising applications for localised chemotherapeutic drug treatment. The present work investigated the efficiency of a TNA nanosystem for the localised CDDP treatment of nasopharyngeal carcinoma (NPC). Methods: Two models of the TNA nanosystem were prepared: CDDP loaded onto the TNA nanosystem surface (CDDP-TNA) and the other consisted of chitosan-coated CDDP-TNA. CDDP release from these two nanosystems was comprehensively tested on the NPC cells NPC/HK-1 and C666-1. The NPC cytotoxicity profile of the two CDDP-TNA nanosystems was evaluated after incubation for 24, 48 and 72 hours. Intracellular damage profiles were studied using fluorescence microscopy analysis with Hoechst 33342, acridine orange and propidium iodide. Results: The half-maximal inhibitory concentrations (IC50) of CDDP at 24 hours were 0.50 mM for NPC/HK-1 and 0.05 mM for C666-1. CDDP in the CDDP-TNA and chitosan-coated CDDPTNA models presented a significant degree of NPC inhibition (P<0.05) after 24, 48 and 72 hours of exposure. The outcome revealed cellular damage and shrinkage of the cell membranes after 48 hours of exposure to CDDP-TNA. Conclusion: This in vitro work demonstrated the effectiveness of TNA nanosystems for the localised CDDP treatment of NPC cells. Further in vivo studies are needed to support the findings

Surface Modification and Bioactivity of Anodic Ti6Al4V Alloy

The present study deals with surface modification of Ti6Al4V alloy via anodization technique. The morphology, structure, adhesion and bioactivity of Ti6Al4V alloy after anodization process were investigated in detail. The influence of fluoride content and direct circuit (DC) applied voltage during anodization of Ti6Al4V alloy in a bath with electrolytes composed of ethylene glycol (EG) and ammonium fluoride (NH4F) were considered. It was found that the average pore sizes and length of nanoporous or nanotubes were increasing with the fluoride content and applied voltage. A minimum of 3 wt% of NH4F is required to grow a self-organized nanotube arrays. As the fluoride content was increased to 5 wt%, TiO2 nanotubes with average diameter of 110 nm and 3.4 microm lengths were successfully synthesized. It is noteworthy to point out that the rate of the nanotube formation was increasing up to 9 microm thick bioactive TiO2 nanotubes layer as anodization time was increased to 3 h. Based on the results obtained, the PA6 cells cultured on anodic Ti6Al4V alloy showed highest level of cell viability and greater cell adhesion compared to the flat Ti6Al4V foil substrate. In fact, highly ordered nanotubes structure on Ti6Al4V alloy can provide beneficial effects for PA6 cells in attachment and proliferation

The Effect of Preparation Method on Ni/Ce/Al Catalyst for High Temperature Water-Gas Shift Reaction

High temperature water gas shift (HT-WGS) is an important catalytic process connected with reforming process in hydrogen production. Ni/CeO2-Al2O3 (or Al2O3) catalysts were studied in this work on the effect of catalyst preparation method toward the physicochemical properties and the HT-WGS activity. Ni/CeO2-Al2O3 were prepared by sol-gel and impregnation methods whereas Ni/Al2O3 was prepared by impregnation method. The catalyst samples were characterized by XRD, H2-TPR and H2-TPD techniques. The catalytic activities of HT-WGS catalysts was demonstrated at 550°C, GHSV of 2x105 mLh-1gcat-1and steam-to-CO ratio of 3. Nickel was detected as a nickel aluminate phase in the calcined catalyst. Ni strongly interacted with support in the calcined catalyst prepared by sol-gel method. The strong metal-support interaction can be resisted by preparing catalyst via impregnation and CeO2 can promote the H2O dissociation in HT-WGS mechanism. The highest metal dispersion, largest metal surface area and greatest HT-WGS activity were consequently achieved by Ni/CeO2-Al2O3 prepared from impregnation method

Low Temperature Synthesis of MgFe2O4 Soft Ferrite Nanocrystallites

Single phase soft ferrite nanocrystallites could be synthesized by various methods. Most of the methods start from preparation of powder or they are high temperature synthesis. We have tried to synthesize MgFe2O4 nanocrystallites at low temperature to improve their properties. MgFe 2O4 magnetic particles with crystallite size (∼7.4nm) were successfully synthesized below 200°C by auto-combustion assisted sol-gel method with the control of pH value and hydrolysis conditions. The pH dependent combustion nature has been studied by thermal analysis (DTA and TG) of the dried gel. The formation of single phase cubic spinel was confirmed by XRD analysis. The morphology of the powder was characterized by FESEM. It represents a soft agglomerated structure composed of magnetically interacting ultrafine crystallites. These nanocrystallites synthesized at low temperature improved electrical and magnetic properties and the results discussed

Shelf-life, bioburden, water and oxygen permeability studies of laser welded SEBS/PP blended polymer

Abstract The most common material used for blood bags is PVC, which requires the addition of DEHP to increase its flexibility. DEHP is known to cross the polymer barrier and move into the stored blood and, ultimately, the patient's bloodstream. In this work, an alternative prototype composed of SEBS/PP was fabricated through blow-moulding and compared with the commercially available PVC-based blood bag which was designated as the control. The blow-moulded sample layers were welded together using CO2 lasers and optimized to obtain complete sealing of the sides. The samples' performance characteristics were analyzed using water permeability, oxygen permeability, shelf-life, and bioburden tests. The SEBS/PP sample exhibited the highest oxygen permeability rate of 1486.6 cc/m2/24 h after 40 days of ageing, indicating that the sample is conducive for red blood cell (RBC) respiration. On the other hand, the SEBS/PP sample showcased a lower water permeability rate of 0.098 g/h m2 after 40 days of aging, indicating a high-water barrier property and thus preventing water loss during storage. In comparison, the oxygen and water permeability rates of PVC-DEHP were found to be distinctly lower in performance (662.7 cc/m2/24 h and 0.221 g/h m2, respectively). In addition, shelf-life analyses revealed that after 40 days of ageing, polymer samples exhibited no visual damage or degradation. The optimal parameters to obtain adequate welding of the SEBS/PP were determined to be power of 60% (18 W), speed of 70 in/sec and 500 Pulse Per Inch (PPI). Furthermore, the bioburden estimates of SEBS/PP of 115 CFU are markedly lower compared to the bioburden estimate of PVC-DEHP of 213 CFU. The SEBS/PP prototype can potentially be an effective alternative to PVC-based blood bags, particularly for high-risk patients in order to reduce the likelihood of medical issues

Genome-nanosurface interaction of Titania Nanotube Arrays: evaluation of telomere, telomerase and NF-κB activities on epithelial cell model

Titanium Dioxide Nanotube Arrays (TNA) provides promising platform for medical implants and nanomedicine applications. The present cell-TNA study has provided profound understanding on protection of genome integrity via telomere, telomerase and NF-κB activities using epithelial cell model. It has been revealed in this study that cell-TNA interaction triggers the telomere shortening activity and inhibition of telomerase activity at mRNA and protein level. The present work supported that cell-TNA stimulus might involve controlled transcription and proliferative activities via NBN and TERF21P mechanisms. Moreover, inhibition of NF-κB may promote molecular sensitivity via senescence -associated secretory phenotype activities and might results in reduced inflammatory response which would be good for cell and nanosurface adaptation activities. Thus, this nanomaterial-molecular knowledge is beneficial for further nanomaterial characterization and advanced medical application

Biodegradable potential of LLDPE/TiO2-ZnO film in soil and hydrolytic systems targeted for healthcare-related product

Medical-grade polymers present challenges in long-term healthcare waste management due to resistance in degradation mechanisms. Collaborative nanocomposite technology in biomedical polymers holds promise for enhancing biodegradability. This study examined the biodegradability of LLDPE/TiO2-ZnO film in various environmental conditions (compost soil, pond soil, coastline, and landfill soil, hydrolytic and simulated body fluid models) and further assessment using field emission scanning electron microscopy (FESEM) and Coupled Plasma Optical Emission spectroscopy. Nanocomposite present in LLDPE polymer could enhance the biodegradability potential of the film possibility via hydrolysis and free radicals’ activities, especially in high moisture content environment. Deformation holes in the film were observed via FESEM confirming degradability activities. The biodegradability rate is also could be influenced by microbe-rich environments. The insights gained from this study have the potential to contribute to the advancement of biodegradable polymers and the improvement of waste management technology in the healthcare industry