Fig. 3. Physicochemical characterization of the nanostructures. (A) FTIR spectra of cisplatin (Pt(ii), active drug, dark blue), compound 1 (Pt(iv) precursor, light blue) and MnO₂–Pt(iv) NPs (2, red). *Main peaks mentioned in the discussion. (B) UV-Vis absorption spectra of the nanostructures 2, showing a broad absorption around 350 nm. (C) Expanded region of XPS spectra of MnO₂–Pt(iv) nanoparticles showing the peaks at region Mn2p.⁴⁴ (D) Expanded Mn3s region of XPS spectra of MnO₂–Pt(iv) NPs and table with reference magnitudes of peak splitting of different Mn oxidation states.⁴⁴ (E) Expanded Pt4f region of XPS spectra and table with reference binding energies of common Pt states in the Pt4f region.⁴⁵.