Investigation of structural properties of forsterite coating on AZ91 magnesium alloy by sol-gel method

This study examined the synthesis and characterization of a nanostructured forsterite coating on a biodegradable AZ91 alloy to enhance its bioactivity. The coating was applied using sol-gel technique, resulting in a homogeneous and crack-free surface as confirmed by scanning electron microscopy. X-ray diffraction was used to identify the phases present in the coating, which confirmed the presence of forsterite particles with an average size of 35 nm. To evaluate the effectiveness of the coating, potentiodynamic polarization electrochemical tests were conducted in simulated body fluid (SBF), which showed that the corrosion current density decreased from 11 μA cm−2 for uncoated samples to 4.3 μA cm−2 for coated samples. Moreover, the surface of the coated magnesium alloy showed fewer cracks and cavities after being immersed in SBF for 672 h. Given that the early degradation of magnesium alloy poses challenges for prostheses and bone stabilizers, this coating could promote bone healing and positive interaction with bone tissue while preventing toxicity from metal ions

Preparation and Evaluation of Inhalable Itraconazole Chitosan Based Polymeric Micelles

Background: This study evaluated the potential of chitosan based polymeric micelles as a nanocarrier system for pulmonary delivery of itraconazole (ITRA).Methods: Hydrophobically modified chitosan were synthesized by conjugation of stearic acid to the hydrophilic depolymerized chitosan. FTIR and 1HNMR were used to prove the chemical structure and physical properties of the depolymerized and the stearic acid grafted chitosan. ITRA was entrapped into the micelles and physicochemical properties of the micelles were investigated. Fluorescence spectroscopy, dynamic laser light scattering andtransmission electron microscopy were used to characterize the physicochemical properties of the prepared micelles. The in vitro pulmonary profile of polymeric micelles was studied by an air-jet nebulizer connected to a twin stage impinger.Results: The polymeric micelles prepared in this study could entrap up to 43.2±2.27 μg of ITRA per milliliter. All micelles showed mean diameter between 120–200 nm. The critical micelle concentration of the stearic acid grafted chitosan was found to be 1.58×10-2 mg/ml. The nebulization efficiency was up to 89% and the fine particle fraction (FPF) varied from 38% to 47%. The micelles had enough stability to remain encapsulation of the drug during nebulization process.Conclusions: In vitro data showed that stearic acid grafted chitosan based polymeric micelles has a potential to be used as nanocarriers for delivery of itraconazole through inhalation