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By altering some synthesis variables, the morphology and structural properties of anodic TiO2 nanotube arrays (TiO2NTs) can be tailored to a specific application. This study aims to investigate the effect of electrolyte-containing ions from human plasma and annealing temperature on structural, morphological, and mechanical parameters of TiO2NTs films, targeting its potential biomedical applications. Bio-inspired TiO2NTs were grown from Ticp and its Ti6Al4V alloy by potentiostatic anodization in the recently developed SBF-based electrolyte, maintained at 10 °C and 40 °C. The thermal investigation was performed by TGA/DSC and used to define the phase transition temperatures used for annealing (450 °C and 650 °C). Morphological and structural parameters were evaluated by FE-SEM, XRD, contact angle measurements, and nanoindentation. Results show that self-organized as-formed TiO2NTs were grown under all synthesis conditions with different wettability profiles for each substrate group. At 450 °C annealing temperature, the beginning of nanostructures collapse starts, becoming evident at 650 °C. The nanoindentation characterization reveals that both electrolyte and thermal annealing exhibited low effects on the hardness and Young’s modulus. The tailoring of specific properties by different synthesis conditions could allow the individualization of treatments and better performance in vivo. [ABSTRACT FROM AUTHOR]

Modifications of Ti-based surface are increasingly studied to improve biological responses on the biomedical implants field. In this study, nanotubular arrays were grown from Ticp (T) and its alloy, Ti6Al4V (A), by potentiostatic anodization at 25 V for 90 min in ethylene glycol media containing 0.75% w/w of NH4F, H2O 9% v/v and 1% v/v of Simulated Body Fluid (SBF) maintained at 10 °C (T10 and A10) and 40 °C (T40 and A40) for drug release studies. Coatings were top filled with cefazolin (1 mg) and the releasing procedure was performed in 5 mL of PBS at 37 °C, taking 0.5 mL aliquots at 1, 4, 7, 10, 15 and 30 min. The as-formed coatings were characterized by Scanning Electron Microscopy (SEM), X-rays Diffraction (XRD) and contact angle measurements. Contact angle measurements indicate that T-based nanotubular coatings are highly wettable, being 0.00° and 6.74° ± 1.96 for T10 and T40 respectively. Coatings obtained from Ti-alloy exhibits low wettability than T-based samples for both temperatures. All samples release the drug on short time intervals (4 to 10 min). The drug release rate is inversely proportional to the contact angle, considering substrate groups. Thus, a higher wettability tendency presents a higher release rate. This result shows that wettability is an important parameter to be considered in the design of Ti-based biomaterials. [ABSTRACT FROM AUTHOR]

Modified titanium nanotubes (TiO2NTs) coatings are grown in simulated body fluid (SBF) from Ticp and Ti6Al4V. The addition of 1% v/v of SBF to the electrolyte neither modifies film morphology nor the structural oxide characteristics for both metal substrates. However, an improvement in mechanical properties (hardness and elasticity model) and wettability is observed. From bioactive assay, a higher amount of fluorapatite was detected on the top of TiO2NTs prepared in SBF‐based electrolyte. [ABSTRACT FROM AUTHOR]

This study innovates in comparing biological activities and chemical composition obtained from extracts and fractions from Pereskia aculeate leaves. Seven extracts and five fractions were produced by conventional successive solid-liquid extraction coupled with simultaneous bioguided purification using solvents of distinct polarities. A comparative analysis was conducted between these purified fractions and the original extracts to elucidate potential improvements in the bioactivity. The extract and fractions were evaluated using the ABTS, DPPH, FRAP, and Folin-Ciocalteau methods and HPLC-DAD and UHPLC-ESI-Q-TOF-MS/MS evaluated chemical composition. The fractions obtained from the hydroalcoholic extract showed better results, with the acetone fraction (Fr-Ace) exhibiting enhanced bioactivity, especially in the FRAP (1095 μmol of FeSO 4 /g) antioxidant capacity method. The results demonstrated that medium to high polarity solvents were the most effective in extracting bioactive phenolic compounds, with rutin being the predominant compound. The sequential hydroalcoholic fractionation (SHF) method extracted a greater variety of compounds, including vanillic acid and cinnamic acid, which were reported for the first time in P. aculeate leaves. The identified compounds by UPLC-Q-TOF-MS/MS included flavonoids derived from quercetin, isorhamnetin, and kaempferol, phenolic acids, and their derivatives. Quercetin-3- O -xyloside, kaempferol-3- O -arabinoside, trehalose, feruloyltyramine, malyngic acid, pinellic acid, and 16-hydroxy-9-oxooctadeca-10,12,14-trienoic acid were identified for the first time in P. aculeata leaves., Competing Interests: The authors declare no competing financial interest., (© 2024 The Authors. Published by American Chemical Society.)

By altering some synthesis variables, the morphology and structural properties of anodic TiO 2 nanotube arrays (TiO 2 NTs) can be tailored to a specific application. This study aims to investigate the effect of electrolyte-containing ions from human plasma and annealing temperature on structural, morphological, and mechanical parameters of TiO 2 NTs films, targeting its potential biomedical applications. Bio-inspired TiO 2 NTs were grown from Ti cp and its Ti6Al4V alloy by potentiostatic anodization in the recently developed SBF-based electrolyte, maintained at 10 °C and 40 °C. The thermal investigation was performed by TGA/DSC and used to define the phase transition temperatures used for annealing (450 °C and 650 °C). Morphological and structural parameters were evaluated by FE-SEM, XRD, contact angle measurements, and nanoindentation. Results show that self-organized as-formed TiO 2 NTs were grown under all synthesis conditions with different wettability profiles for each substrate group. At 450 °C annealing temperature, the beginning of nanostructures collapse starts, becoming evident at 650 °C. The nanoindentation characterization reveals that both electrolyte and thermal annealing exhibited low effects on the hardness and Young's modulus. The tailoring of specific properties by different synthesis conditions could allow the individualization of treatments and better performance in vivo ., (© 2021 IOP Publishing Ltd.)