Bis-ADC complexes cis-[Pd{C(NHC₆H₄NH₂)N(H)R}₂]Cl₂ (R = Xyl 4a, Cy 4b, C₆H₄-4-F 4c) and cis-[Pt{C(NHC₆H₄NH₂)N(H)R}₂]Cl₂ (R = Xyl 5a, Cy 5b, C₆H₄-4-F 5c) were synthesized via the metal-mediated coupling of two isocyanide ligands in cis-[MCl₂(CNR)₂] (M = Pd, Pt; R = Xyl, Cy, C₆H₄-4-F) and 1,2-diaminobenzene. New compounds 4c and 5a–c were characterized by HR ESI⁺-MS, IR, and ¹H, ¹³C{¹H} and ¹⁹⁵Pt{¹H} NMR spectroscopy; the structures of 4a and 5a were elucidated by single-crystal X-ray diffraction. The stability of the ADC complexes in aqueous media (5 mM NaCl) was monitored by UV absorption spectroscopy, HR ESI⁺ mass spectrometry, and ¹⁹⁵Pt{¹H} NMR spectroscopy (for 5a). Molar conductivity measurements in MeOH (Λ_M = 167–173 Ω⁻¹ mol⁻¹ cm²) indicate that, in this solvent, the ADC complexes exist as dicationic species of [A][Q]₂ type. The ADC complexes binding to CT DNA was investigated by means of spectroscopic and hydrodynamic techniques including UV absorption and circular dichroism spectroscopy, fluorescence spectroscopy, low-gradient viscometry, flow birefringence, and AFM imaging. As a result, complexes 4a and 5a were shown to bind double-stranded DNA predominantly via the formation of monofunctional adducts in the major groove of the macromolecule. Binding of the ADC complexes also provokes the formation of a large number of intermolecular DNA–DNA contacts in solution. The antiproliferative activity of all prepared ADC complexes 4a–c and 5a–c was evaluated in vitro against three human carcinoma cell lines (HT-29, MDA-MB-231, and MCF-7) and two non-tumorigenic cell lines (L929 and RC-124) and compared to that of cisplatin. Among the compounds studied, complexes 4a and 5a appeared to be the most active species with IC₅₀ values in MCF-7 cells of about 10 μM.

DNA interaction with silver and aluminum nanoparticles in a solution has been investigated with the AFM, SEM, dynamic light scattering, viscometry, and spectral methods. The comparison of DNA interaction with nanoparticles synthesized by the reduction of Ag⁺ions and with nanoparticles obtained by the electric discharge plasma method was done. DNA metallization in a solution and onn-silicon surface with metal nanoparticles or by the reduction of silver ions after their binding to DNA was executed and studied. It was shown that DNA strands with regular location of silver or aluminum nanoparticles can be prepared. The conditions for the formation of silver nanoparticles and silver nanoclusters on DNA were analyzed.

The study of DNA interaction with the acetate bis(1,10-phenanthroline)silver(I) monohydrate in a solution is of interest both for understanding the mechanism of biological activity of silver compound and for forming ordered structures (DNA fibrils) that can be used to solve various problems in the field of nanotechnology. The analysis of changing the DNA conformation (secondary structure, persistent length and volume effects) during the interaction by the methods of UV spectroscopy with the analysis of DNA melting, circular dichroism, viscosity, flow birefringence, AFM (atomic force microscopy) and SEM (scanning electron microscopy) was performed. The formation of two types of complexes was observed. At lower concentration of compound in DNA solution, silver atoms form the coordination bonds with a macromolecule, while the released phenanthroline ligands intercalate between DNA bases. When the concentration of the compound increases, the phenanthroline ligands form an ordered “layer” around the helix. The excess of silver compounds in the DNA solution (with more than five silver atoms per base pair), DNA precipitation is observed with the formation of long fibrils. It was shown that the binding of silver to DNA during the formation of complexes provides further metallization of the resulting structures with the aid of reducing agents; phenanthroline ligands influence the result of such metallization.