SERS/TERS Characterization of New Potential Therapeutics: The Influence of Positional Isomerism, Interface Type, Oxidation State of Copper, and Incubation Time on Adsorption on the Surface of Copper(I) and (II) Oxide Nanoparticles

α-Amido sulphones as useful intermediates in the preparation of C-chiral α-aminophosphonates and α-aminophosphonic acids

α-Amido sulphones have been used as useful starting materials in the preparation of C-chiral α-aminophosphonates and α-aminophosphonic acids. The developed methodology is based on a one-pot, base-catalysed in situ generation of an imine intermediate followed by addition of a phosphorus nucleophile. The presented protocol is simple and effective and can be applied to a variety of structurally diverse α-amido sulphones and phosphorus nucleophiles, leading to the desired pure products after simple crystallization in very good yields. Importantly, the use of H-phosphonate bearing a chiral auxiliary allows the reaction to be performed with high diastereoselectivity (a single diastereoisomer is generated and isolated) and the possibility of precise control of the configuration at the newly generated C-chiral centre.

Metallic nanoparticles as effective sensors of bio-molecules

This work describes biologically important nanostructures of metals (AgNPs, AuNPs, and PtNPs) and metal oxides (Cu₂ONPs, CuONSs, γ-Fe₂O₃NPs, ZnONPs, ZnONPs-GS, anatase-TiO₂NPs, and rutile-TiO₂NPs) synthesized by different methods (wet-chemical, electrochemical, and green-chemistry methods). The nanostructures were characterized by molecular spectroscopic methods, including scanning/transmission electron microscopy (SEM/TEM), energy dispersive X-ray spectroscopy (EDS), X-ray diffraction analysis (XRD), photoelectron spectroscopy (XPS), ultraviolet-visible spectroscopy (UV-vis), dynamic light scattering (DLS), Raman scattering spectroscopy (RS), and infrared light spectroscopy (IR). Then, a peptide (bombesin, BN) was adsorbed onto the surface of these nanostructures from an aqueous solution with pH of 7 that did not contain surfactants. Adsorption was monitored using surface-enhanced Raman scattering spectroscopy (SERS) to determine the influence of the nature of the metal surface and surface evolution on peptide geometry. Information from the SERS studies was compared with information on the biological activity of the peptide. The SERS enhancement factor was determined for each of the metallic surfaces.

Spectroscopic characterization and in vitro studies of biological activity of bradykinin derivatives

Eleven multiple analogs of bradykinin-a peptide that is a natural ligand of B1 and B2 receptors but does not bind or activate the B1 receptor unless Arg⁹ is removed from the sequence by the action of carboxypeptidase N-were synthesized. Their biological activity was examined on T-REx cell lines expressing B1 or B2 receptors using the intracellular IP1 assay. The mRNA expression of B1R and B2R in the lysate of tumor cell lines, e.g., U87-MG (human astrocytoma), SHP-77 (human small cell lung cancer), and H4 (human brain glioma), was determined. For five B1R antagonists, adsorption at the liquid/solid interface (Au nanoparticles (AuNPs) served as the solid surface) was discussed in terms of the vibrations of molecular fragments (structural factors) responsible for the biological properties of these analogs.