Corrosion inhibitors are substances that reduce or eliminate the corrosion of a metal in a certain environment. Corrosion inhibitors act by several mechanisms, including adsorption, film formation, passivation, and oxygen scavenging. Due to their toxicity, classic corrosion inhibitors affect the environment. Therefore, in recent years, more and more studies have focused on the development of eco-friendly inhibitors for the environment. In this study, ethanolic extract of Galium verum (GV) was tested for the inhibition of steel corrosion in 1 M HCl medium using electrochemical methods: open circuit potential (OCP), potentiodynamic polarization (PP), and electrochemical impedance spectroscopy (EIS). Reverse-phase liquid chromatography (HPLC) and gas chromatography mass spectrometry (MS-GC) previous studies state that GV extract contains polyphenols and other chemical species responsible for the inhibitory effect. Corrosion investigations have highlighted the influence of the concentration of the GV extract, in the range of 50 ÷ 400 ppm G.A.E./mL, as well as the influence of temperature in the range of 20 ÷ 50 °C. The corrosion inhibitory efficiency of the Galium verum ethanolic extract had a maximum value of 91.82% for a concentration of 400 ppm polyphenol content, demonstrating the inhibitory potential of this green product in an acidic environment for mild steel. Statistical calculus on the obtained values of EIS inhibitor efficiency showed that the effect of the extract becomes stronger at higher concentrations.

Plant-derived corrosion inhibitors are increasingly investigated due to their rich content of adsorption-active phytochemicals. Four extracts obtained from Achillea millefolium were biochemically characterized through spectrophotometric and chromatographic analyses, confirming a substantial polyphenolic content and associated antioxidant capacity. In addition, the hydroethanolic extract (1:1) was examined for its ability to inhibit the corrosion of S235 mild steel in 1 M HCl and neutral medium of 3.5% NaCl by gravimetry, potentiodynamic polarization, open-circuit potential, and electrochemical impedance spectroscopy methods, suggesting that its antioxidant molecules may contribute to the passivation of the metal surface, but in different mechanistic ways. The inhibitory efficiency determined by both the gravimetric method and the Taffel polarization curve method reaches values of 78.53% in HCl 1 M and of 79.65% in NaCl 3.5%, thus demonstrating the contribution of polyphenols from the Achillea millefolium extracts to the inhibition of corrosion.

Flunarizine is a calcium channel blocker widely used in neurological disorders; however, its low aqueous solubility may influence formulation stability and drug dispersion in polymer-based systems. The present study aimed to evaluate the compatibility of flunarizine with selected excipients and to investigate its incorporation into polymeric hydrogel matrices. Binary mixtures of flunarizine with excipients such as hydroxypropyl-β-cyclodextrin, polyethylene glycol (PEG 6000), Tween 20, gelatin, and citric acid were prepared and characterized using Fourier-transform infrared spectroscopy (FTIR), thermogravimetric analysis (TG/DTG), and high-performance liquid chromatography (HPLC). The FTIR spectra of the analyzed samples do not reveal the appearance of new absorption bands that may indicate chemical interactions; instead, minor spectral variations were observed due to weak intermolecular interactions within the polymer network. Thermal analysis revealed decomposition patterns consistent with those of the individual components, suggesting the absence of significant incompatibilities. A validated RP-HPLC method enabled sensitive and reliable quantification of flunarizine in the analyzed systems, with a limit of detection (LOD) of 0.05 µg/mL and a limit of quantitation (LOQ) of 0.16 µg/mL. Accuracy testing showed average recovery rates of 100% across 80–120% spiking levels. Overall, the results support the compatibility of flunarizine with the investigated excipients and the suitability of the studied hydrogels as potential drug delivery matrices.

The thienopyridine derivative—prasugrel hydrobromide—is commonly used as an antiplatelet drug to prevent thrombotic events. Its physicochemical properties indicate susceptibility to environmental factors such as light and humidity, which can affect its solid-state stability and, consequently, its pharmaceutical behaviour. Knowledge of the solid-state stability profile of this compound is essential to enable control of processing and storage conditions. The objective was to assess the effects of light and moisture on prasugrel hydrobromide and its binary mixtures with different pharmaceutical excipients. Samples were stored at room temperature (approximately 60–70% relative humidity) for seven days in open glass containers. Assessment was performed by FTIR-ATR spectroscopy and thermal analysis (TG/HF). Measurements showed that exposure to humidity induced detectable and reversible structural and thermal changes, most of which were associated with moisture adsorption and hydrogen-bond rearrangements. This study demonstrates the importance of environmental control during storage, and further studies to understand behaviour as a function of moisture are essential for ensuring the long-term stability of prasugrel hydrobromide in solid pharmaceutical formulations.

Due to their diverse phytochemical composition, medicinal plants belonging to the families Amaryllidaceae, Lamiaceae, and Myrtaceae possess antimicrobial and antioxidant properties. In this study, six ethanolic extracts of Allium ursinum, Allium sativum, Allium cepa, Salvia rosmarinus, Ocimum basilicum, and Syzygium aromaticum were analyzed by HS-SPME GC-MS and HPLC. Their chemical composition was evaluated and compared by chemometrics and their biological activity determined by an antimicrobial assay. A total of 72 compounds was detected (terpenoids, phenolic derivatives, fatty acids, and phytosterols). In Allium species, phytosterols were mainly abundant, whereas O. basilicum extracts were characterized by high contents of linalool and S. rosmarinus by 2-hydroxychalcone and 4-hydroxybutanoic acid lactone. Principal component analysis distinguished chemically species-specific chemical profiles, whilst the HPLC evaluation resulted in the highest quercetin content in S. rosmarinus extracts, which also displayed the best antibacterial effect against Staphylococcus aureus. Despite the observed correlation between the quercetin content and antibacterial activity, no definitive relation could be established without biological replicates, MIC evaluation, and tests with isolated compounds.