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New, electroactive, positively charged peptides consisting of either L‐lysine or L‐arginine and containing one or two anthraquinone units in the structure were synthesized. Electrochemical properties of the synthesized compounds were examined by cyclic‐, normal pulse‐ and microelectrode voltammetries. Spectroscopic and potentiometric methods were used to characterize such properties of the new peptides as: pKa, diffusion coefficients and formal potentials in water and DMSO. The obtained results show that the number of noninteracting, anthraquinone units incorporated into one peptide chain leads to proportional increase of height of voltammetric and spectroscopic signals.

Protonation of gossypol Schiff bases (S1 and S2), possessing different numbers of basic N-atoms, was studied using potentiometric, spectroscopic, ESI MS and PM5 methods. Titration of S1 and S2 with HClO(4), monitored by the FT-IR and (1)H NMR, indicated that the change from the enamine-enamine into the protonated imine-imine tautomeric form occurs at different Schiff base-H(+) ratio. The FT-IR and PM5 results show that for S1 the first protonation step occurs at Schiff base moiety whereas for S2 it is realised at N-atom of the morpholine. The formation of N(+)-HO hydrogen bond between morpholine moieties within S2 contributes to high pK(a(ACN)) = 22.65.

An electrochemical oxidation using a highly boron‐doped diamond (BDD) electrode has been tested for the treatment of solutions containing ionic liquids (ILs). The double‐sided Si/highly BDD electrodes were synthesized by microwave plasma enhanced chemical vapour deposition (MW PE CVD). Investigation of the electrode surface with scanning electron microscopy (SEM) confirmed that the synthesized layers were continuous and formed densely packed grain structure. The structure of BDD was confirmed by Raman spectra analysis. The effect of IL structure as the kind of electrolyte (Na2SO4 and NaCl) has been investigated. Electrolyses were conducted in an undivided electrolytic cell under galvanostatic conditions. The efficiency of the process has been evaluated in terms of variations of IL concentrations and chemical oxygen demand (COD) removal. Results show that pyridinium ILs were easier removed than imidazolium salts. The intermediates of electrochemical degradation of 1‐butyl‐3‐methylimidazolium salt were detected, and IL degradation pathway was proposed based on the analytical results. It was suggested that •OH radicals produced by water electrolysis attacked IL to form its derivatives with keto groups substituted to imidazolium ring. These compounds underwent ring breakage, which led to the formation of aliphatic acids that were eventually mineralized by electrolysis to CO2. Other by‐products were obtained by cutting one of the side chains substituted to N atoms in imidazolium ring. Additionally in NaCl electrolyte chloroorganic by‐products were identified.