This review discusses the significance of natural deep eutectic solvents (NaDESs) as a promising green extraction technology. It employs the consolidated meta-analytic approach theory methodology, using the Web of Science and Scopus databases to analyze 2091 articles as the basis of the review. This review explores NaDESs by examining their properties, challenges, and limitations. It underscores the broad applications of NaDESs, some of which remain unexplored, with a focus on their roles as solvents and preservatives. NaDESs’ connections with nanocarriers and their use in the food, cosmetics, and pharmaceutical sectors are highlighted. This article suggests that biomimicry could inspire researchers to develop technologies that are less harmful to the human body by emulating natural processes. This approach challenges the notion that green science is inferior. This review presents numerous successful studies and applications of NaDESs, concluding that they represent a viable and promising avenue for research in the field of green chemistry.

Photodynamic therapy (PDT) mediated by photosensitizers loaded in nanostructures as solid lipid nanoparticles has been pinpointed as an effective and safe treatment against different skin cancers. Amazon butters have an interesting lipid composition when it comes to forming solid lipid nanoparticles (SLN). In the present report, a new third-generation photosensitizing system consisting of aluminum-phthalocyanine associated with Amazon butter-based solid lipid nanoparticles (SLN-AlPc) is described. The SLN was developed using murumuru butter, and a monodisperse population of nanodroplets with a hydrodynamic diameter of approximately 40 nm was obtained. The study of the permeation of these AlPc did not permeate the analyzed skin, but when incorporated into the system, SLN-AlPc allowed permeation of almost 100% with 8 h of contact. It must be emphasized that SLN-AlPc was efficient for carrying aluminum-phthalocyanine photosensitizers and exhibited no toxicity in the dark. Photoactivated SLN-AlPc exhibited a 50% cytotoxicity concentration (IC₅₀) of 19.62 nM when applied to B16-F10 monolayers, and the type of death caused by the treatment was apoptosis. The exposed phospholipid phosphatidylserine was identified, and the treatment triggered a high expression of Caspase 3. A stable Amazon butter-based SLN-AlPc formulation was developed, which exhibits strong in vitro photodynamic activity on melanoma cells.

Background: Paullinia cupana Kunth, popularly known as guarana, a native Amazonian shrub cultivated by the Sateré-Mawé ethnic group, has been used in traditional medicine for various purposes, including stimulant and therapeutic actions, due to its chemical composition, which is rich in bioactive compounds. This study explored the reductive potential of guarana with nanobiotechnology and aimed to synthesize silver nanoparticles (AgNPs) using the aqueous extract of leaves collected during the dry and rainy seasons, assessing their biological and catalytic activities. Methods: The AgNPs were synthesized in a water bath at 70 °C for three hours and then characterized using techniques such as UV-Vis spectroscopy, DLS, zeta potential, MET, NTA, and EDX and had their effects on various biological systems assessed in vitro, as well as in catalytic tests aimed at indicating the probable influence of the time when the plant material was collected on the properties of the nanostructures. Results: The AgNPs had an average diameter between 39.33 and 126.2 nm, spherical morphology, absorption bands between 410 and 450 nm, and high colloidal stability over two years. The biological results showed antibacterial activity against all the species tested, as well as remarkable antioxidant action against DPPH and ABTS free radicals, in the same way as the aqueous leaf extracts of P. cupana, in addition to cytotoxic properties against cancerous (A431 and A549) and non-cancerous (HaCaT and HNTMC) cells. The AgNPs were active against promastigote forms of Leishmania (Leishmania) amazonensis while not affecting the viability of macrophages, and from the LC₅₀ and LC₉₀ values, the AgNPs were more effective than the metal salt solution in controlling Aedes aegypti larvae and pupae. We also reported that the catalytic degradation of the organic dyes methylene blue (MB) and methyl orange (MO) by AgNPs was over 90% after 40 or 14 min, respectively. Conclusions: Thus, our results support the potential of seasonal extracts of guarana leaves to produce AgNPs with diverse application possibilities for the health, industrial, and environmental sectors.

Photodynamic therapy (PDT) uses a photosensitizer to generate reactive oxygen species (ROS) that kill target cells. In cancer treatments, PDT can potentially induce immunogenic cell death (ICD), which is characterized by a well-controlled exposure of damage-associated molecular patterns (DAMPs) that activate dendritic cells (DCs) and consequently modulate the immune response in the tumor microenvironment. However, PDT still has limitations, such as the activity of photosensitizers in aqueous media and poor bioavailability. Therefore, a new photosensitizer system, SLN-AlPc, has been developed to improve the therapeutic efficacy of PDT. In vitro experiments showed that the light-excited nanocarrier increased ROS production in murine melanoma B16-F10 cells and modulated the profile of DCs. PDT induced cell death accompanied by the exposure of DAMPs and the formation of autophagosomes. In addition, the DCs exposed to PDT-treated B16-F10 cells exhibited morphological changes, increased expression of MHCII, CD86, CD80, and production of IL-12 and IFN-γ, suggesting immune activation towards an antitumor profile. These results indicate that the SLNs-AlPc protocol has the potential to improve PDT efficacy by inducing ICD and activating DCs.

This study explores the development and characterization of lipid nanostructures (NLCs) containing natural deep eutectic solvents (NaDESs) derived from taperebá peel extract (Spondias mombin), a by-product rich in bioactive phenolic compounds, including ellagic acid and quercetin. The taperebá extract exhibited a high polyphenol content (2623 mg GAE/L) and notable antioxidant activity, as demonstrated by DPPH (258 mM TEAC/100 mL) and ABTS (495 mM TEAC/100 mL) assays. NLCs were developed using NaDESs to enhance the stability and bioavailability of the antioxidant compounds. Physicochemical characterization confirmed the formation of stable, nanometric, and monodispersed formulations with efficient encapsulation. Biological evaluation of the NLC-TAP-NaDES formulation demonstrated its remarkable capacity to mitigate oxidative stress in cells subjected to H₂O₂-induced ROS generation. Fluorescence imaging revealed a significant reduction in intracellular ROS levels in treated cells compared to untreated controls, confirming the antioxidant efficacy of the formulation. This outcome underscores the synergy between NaDESs and NLC systems in protecting and delivering phenolic compounds. This study highlights the potential of utilizing underexplored by-products, such as taperebá peels, to develop sustainable and effective antioxidant delivery systems. The NLC-TAP-NaDES platform combines nanotechnology with green chemistry principles, presenting significant implications for the treatment of oxidative stress-related conditions and broader applications in pharmaceutical and nutraceutical sciences. These findings contribute to advancing sustainable innovations in antioxidant therapies, leveraging the dual benefits of bioeconomy and high-performance nanomaterials.

Background/Objectives: Optimizing synthesis parameters is essential to ensure the quality and stability of nanostructures. This study aimed to optimize the synthesis of selenium nanoparticles (SeNPs) by chemical reduction, using sodium selenite (Na₂SeO₃), ascorbic acid (AA), and polyvinyl alcohol (PVA) at different concentrations, volumes, and molar ratios. The effects of reduction time, purification steps, and variations in the concentration of the precursor and reducing agent, as well as in the volume of the stabilizer, on the characteristics of SeNPs were investigated to ensure their long-term stability, maintenance of their properties, and biological applicability. Methods: The SeNPs were analyzed by UV/Vis absorption spectroscopy, Dynamic Light Scattering (DLS), and Transmission Electron Microscopy (TEM), and were also evaluated for antifungal activity against the SC5314 strain of Candida albicans. Results/Conclusions: Monodisperse SeNPs were obtained under high concentrations of Na₂SeO₃ and AA, short reduction time, higher volumes of PVA (2–4 mL), and purification at 24.300× g, presenting a spherical morphology, hydrodynamic diameter of 137.0–171.7 nm, dry diameter of 20–120 nm, polydispersity index of 0.049–0.306, Zeta potential of −7.79 to −19.6 mV, and stability for up to 180 days. In the absence or presence of 1 mL of PVA, the SeNPs were predominantly amorphous. Regarding biological activity, the SeNPs did not exhibit antifungal activity under the experimental conditions in the tested strain. Together, this study provides a comprehensive update on the synthesis of SeNPs under different conditions and their stability over time, contributing to the consolidation of knowledge in the field.