Cyclodextrins (CDs) have largely been investigated during the last decades for their outstanding properties, such as biocompatibility and biodegradability, with wide applications in the pharmaceutical field, among which the formation of inclusion complexes (ICs) with natural or synthetic lipophilic compounds. This review prioritizes the research of recent years (2022–2025), being focused on (1) systematization of the research of ICs based on the structure of the secondary metabolite, namely (i) polyphenols (PPs), (ii) terpenes and terpenoids (TTs), and (iii) alkaloids (Alks); (2) for each type of inclusion complex, the following aspects have been discussed: benefits of complexation, composite materials, and in vitro/in vivo and theoretical studies; and (3) pharmacokinetics and pharmacodynamics, risks, limitations, and perspectives of cyclodextrin inclusion complexes with secondary metabolites.

Angiogenesis is the process of developing new blood vessels from pre-existing ones. This review summarizes the main features of physiological and pathological angiogenesis and those of angiogenesis activation and inhibition. In healthy adults, angiogenesis is absent apart from its involvement in female reproductive functions and tissue regeneration. Angiogenesis is a complex process regulated by the action of specific activators and inhibitors. In certain diseases, modulating the angiogenic balance can be a therapeutic route, either by inhibiting angiogenesis (for example in the case of tumor angiogenesis), or by trying to activate the process of new blood vessels formation, which is the goal in case of cardiac or peripheral ischemia.

Potentiodynamic polarization (PDP) and electrochemical impedance spectroscopy (EIS) were applied to study the inhibitory effect of N-acetylcysteine (NAC) on corrosion inhibition of carbon steel in hydrochloric acid solution. N-acetylcysteine influenced the iron dissolution to a greater extent than the hydrogen evolution reaction acting as a mixed inhibitor, predominantly anodic. The charge transfer resistance (R_ct) gradually increased with the inhibitor concentration. From both methods, the inhibition efficiency (IE) reached a value of 89 ± 1% and NAC adsorption followed the Temkin isotherm. The value of adsorption Gibbs energy (Δ${\mathrm{G}}_{\mathrm{ads}}^{\mathrm{o}}$), around −35 kJ mol⁻¹, indicated a spontaneous adsorption and mixed action mechanism, with NAC chemical adsorption prevailing over physical one. New data will be reported by the computational study, that was performed using the density functional theory (DFT) method in aqueous phase. Quantum chemical descriptors were determined by B3LYP theory level with 6–31G+(d) basis set. Metropolis Monte Carlo atomistic simulation was used to reveal the adsorption configuration and interactions between acetylcysteine molecules and the carbon steel surface. Theoretical results were consistent with the experimental data, showing that the inhibitor action mechanism consisted of mainly chemisorption of its molecules on the carbon steel surface accompanied by van der Waals forces and electrostatic interactions.

In order to anticipate the effect induced by a natural product on the chemical activity of medicines simultaneously administered, spontaneous interactions of certain cancer treatment drugs such as, epirubicin (EPR), gemcitabine (GCT), and paclitaxel (PTX) with limonene (LIM)—a natural compound extracted from orange peel and known as an anticancer agent—were investigated. To estimate the stability of the drugs over time, a current density of 50 mA cm⁻² was applied as an external stimulus between two platinum electrodes immersed in hydrochloric acid solution containing ethyl alcohol/water in the volume ratio of 2/3, in the absence and presence of orange essential oil (limonene concentration of 95%). The concentration variation of chemotherapeutic agents over time was evaluated by UV-Vis spectrophotometry. Kinetic studies have shown a delay in the decomposition reaction of epirubicin and gemcitabine and a paclitaxel activity stimulation. Thus, in the presence of limonene, the epirubicin half-life increased from 46.2 min to 63 min, and from 6.2 min to 8.6 min in gemcitabine case, while for paclitaxel a decrease of half-life from 35.9 min to 25.8 min was determined. Therefore, certain drug-limonene interactions took place, leading to the emergence of molecular micro-assemblies impacting decomposition reaction of chemotherapeutics. To predict drug–limonene interactions, the Autodock 4.2.6 system was employed. Thus, two hydrophobic interactions and five π-alkyl interactions were established between EPR-LIM, the GCT-LIM connection involves four π-alkyl interactions, and the PTX-LIM bridges take place through three hydrophobic interactions and the one π-alkyl. Finally, the decomposition reaction mechanism of drugs was proposed.

The electrochemical behavior of pyridoxine was studied in 0.1 mol × L⁻¹ NaX (X = F, Cl, Br) support electrolyte on a gold electrode using cyclic voltammetry and UV–Vis spectrophotometry. The influence of gold nanoparticles (AuNPs) on the electrochemical behavior of pyridoxine was studied. The experimental results obtained by both cyclic voltammetry and UV–Vis spectrophotometry indicate strong interactions in the B₆ and NaBr/NaCl_AuNP systems, while in the NaF_B₆_AuNP ternary system the results indicate a mechanism of direct electrochemical degradation of vitamin B₆. The experimental results obtained for the electrochemical degradation of pyridoxine, in the presence of chloride and bromide ions, indicate strong interactions in the NaCl_B₆_AuNP and NaBr_B₆_AuNP systems associated with the spectrophotometric identification of the electrogenerated intermediates, while in the presence of fluoride ions no such products are identified. The development of the mechanism of electrochemical degradation of the pyridoxine molecule predicts both the formation of the corresponding electrogenerated intermediates and the steps of electro-incineration in a direct mechanism.

This study provides evidence on the stability of vitamin K₁ (VK) in the form of phytomenadione, in the absence and presence of a therapeutic preparation, as the gold nanoparticles (AuNPs), under the effect of sodium halide ions. The degradation susceptibility of the two compounds was assessed individually and in mixtures by cyclic voltammetry and electrolysis at a constant current density assisted by UV-Vis spectrophotometry. Their interactions with the halide ions differently impact on the electrochemical processes as follows: (i) the fluoride ions weakly affects the VK/AuNP stability and compatibility; (ii) the presence of chloride ions leads to VK/AuNP stability, for a short time and restrictive compatibility; (iii) bromide ions induce instability and incompatibility of the VK/AuNP system; (iv) spontaneous interactions between VK/AuNPs and iodide ions take place, consequently defining as an unstable and incompatible system.