Au NPs on ZnFe₂O₄ enhances visible absorption, employed for paracetamol oxidation, where peaks were resolved by 2D HPLC.

Chia (Salvia hispanica L.) seeds contain antioxidants with great benefits for health and are widely used in the food industry. Antioxidants can be degraded by environmental factors, decreasing their biological activity. Their encapsulation in chitosan (CH) particles represents an alternative to protect them and increases their application. The encapsulation efficiency (EE) of the antioxidants in the CH particles depends on the synthesis conditions. In this study, two methods for encapsulation of chia extract in chitosan particles were evaluated: method A, 0.05 CH in 1 acetic acid was mixed with 0.07 of tripolyphosphate (TPP) and method B, 0.3 CH in 2 acetic acid was mixed with 1 TPP. The results showed that the EE decreased with the concentration of the extract, and the FTIR analysis suggested that the compounds of the extract were adsorbed on the surface of the particles. Dynamic light scattering and zeta potential analysis showed that the particles of method A are unstable and with a tendency to agglomerate, and the particles of method B are stable. The highest EE was obtained with 0.2mg·mL⁻¹ (method A) and 1.0mg·mL⁻¹ (method B) of the extract. The higher loading capacity (LC) (1672) was exhibited by the particles of method A. The best particle yield (6269) was observed for method B. The particles with the extract adsorbed showed antioxidant activity (560) at 25°C; however, in the particles with the extract encapsulated, the activity increased after subjecting to acidic conditions at 40°C due to the breakdown of the particles. The results obtained will allow choosing the appropriate conditions for the synthesis of chitosan particles loaded with chia extracts with specific characteristics (EE, LC, size, and type) according to their future applications. The particles could be used in food and pharmaceutical industries and even in edible films for food packaging.

The pH- and thermo-responsive behavior of polymeric hydrogels $\left({\mathrm{M}}_{\mathrm{C}}-\mathrm{c}\mathrm{o}-{\mathrm{M}}_{\mathrm{A}}\right)$ have been studied in detail using dynamic light scattering $\left(\mathrm{D}\mathrm{L}\mathrm{S}\right)$, scanning electron microscopy$\left(\mathrm{S}\mathrm{E}\mathrm{M}\right)$, nuclear magnetic resonance (¹H NMR) and rheology to evaluate the conformational changes, swelling–shrinkage, stability, the ability to flow and the diffusion process of nanoparticles at several temperatures. Furthermore, polymeric systems functionalized with acrylic acid $\left({\mathrm{M}}_{\mathrm{C}}\right)$ and acrylamide $\left({\mathrm{M}}_{\mathrm{A}}\right)$ were subjected to a titration process with a calcium chloride $\left({\mathrm{C}\mathrm{a}\mathrm{C}\mathrm{l}}_2\right)$ solution to analyze its effect on the average particle diameter$\left({\mathrm{D}}_{\mathrm{z}}\right)$, polymer structure and the intra- and intermolecular interactions in order to provide a responsive polymer network that can be used as a possible nanocarrier for drug delivery with several benefits. The results confirmed that the structural changes in the sensitive hydrogels are highly dependent on the corresponding critical solution temperature $\left(\mathrm{C}\mathrm{S}\mathrm{T}\right)$ of the carboxylic (–COOH) and amide (–CONH₂) functional groups and the influence of calcium ions $\left({\mathrm{C}\mathrm{a}}^{2+}\right)$ on the formation or breaking of hydrogen bonds, as well as the decrease in electrostatic repulsions generated between the polymer chains contributing to a particle agglomeration phenomenon. The temperature leads to a re-arrangement of the polymer chains, affecting the viscoelastic properties of the hydrogels. In addition, the diffusion coefficients $\left(D\right)$ of nanoparticles were evaluated, showing a closeness among with the morphology, shape, size and temperature, resulting in slower diffusions for larger particles size and, conversely, the diffusion in the medium increasing as the polymer size is reduced. Therefore, the hydrogels exhibited a remarkable response to pH and temperature variations in the environment. During this research, the functionality and behavior of the polymeric nanoparticles were observed under different analysis conditions, which revealed notable structural changes and further demonstrated the nanoparticles promising high potential for drug delivery applications. Hence, these results have sparked significant interest in various scientific, industrial and technological fields.

Cinnamomum verum, Origanum majorana, and Origanum vulgare have been used in traditional medicine for a long time to treat diabetes because of their promising therapeutic effects. The combination of these plants (COO) was tested to improve their efficacy using selenium nanoparticles (Se-COO-NPs) and gum Arabic (GA) as stabilizers for sustained release. Phenolic compounds of plants were identified using liquid chromatography–mass spectrometry (LC–MS/MS). GA-Se-COO-NPs were characterized by spectroscopic and microscopic methods and evaluated in diabetic zebrafish. The ultraviolet spectrum was assessed to confirm the formation of plasmon resonance at 267 nm. The obtained particle size of selenium nanospheres was 65.76 nm. They were maintained in a stable form for 5 months at 4 °C. Transmission electron microscopy (TEM) images demonstrated the presence of individual spherical nanoparticles. Fourier transform infrared spectroscopy (FT-IR) showed the interaction between COO extract and selenium, exhibiting good entrapment efficiency (87%). The elemental analysis of COO extract and GA-COO-SeNPs confirmed that NPs were obtained. The zebrafish were exposed to a high glucose concentration for two weeks, and type 2 diabetes and oxidative stress responses were induced. In diabetic zebrafish, treatment with NPs showed antilipidemic and hypoglycemic effects, high survivability, and reduced levels of glucose, reactive oxygen species (ROS), and lipids in the blood. This group this had a higher survivorship rate than the diabetic control. The results demonstrated that GA-Se-COO-NPs have high antidiabetic potential, most likely because of the synergic effects of phenolic compounds and Se nanoparticles.

Alzheimer’s disease is associated with protein aggregation, oxidative stress, and the role of acetylcholinesterase in the pathology of the disease. Previous investigations have demonstrated that geniposide and harpagoside protect the brain neurons, and cerium nanoparticles (CeO₂ NPs) have potent redox and antioxidant properties. Thus, the effect of nanoparticles of Ce NPs and geniposide and harpagoside (GH/CeO₂ NPs) on ameliorating AD pathogenesis was established on AlCl₃-induced AD in mice and an aggregation proteins test in vitro. Findings of spectroscopy analysis have revealed that GH/CeO₂ NPs are highly stable, nano-size, spherical in shape, amorphous nature, and a total encapsulation of GH in cerium. Treatments with CeO₂ NPs, GH/CeO₂ NPs, and donepezil used as positive control inhibit fibril formation and protein aggregation, protect structural modifications in the BSA-ribose system, have the ability to counteract Tau protein aggregation and amyloid-β1–42 aggregation under fibrillation condition, and are able to inhibit AChE and BuChE. While the GH/CeO₂ NPs, treatment in AD induced by AlCl₃ inhibited amyloid-β1–42, substantially enhanced the memory, the cognition coordination of movement in part AD pathogenesis may be alleviated through reducing amyloidogenic pathway and AChE and BuChE activities. The findings of this work provide important comprehension of the chemoprotective activities of iridoids combined with nanoparticles. This could be useful in the development of new therapeutic methods for the treatment of neurodegenerative diseases.