The water oxidation is the limiting step in the water-splitting process. Given this scenario, the development of new catalysts is essential in this field. The emergent demand is the use of Earth-abundant elements and catalysts with high performance under mild conditions. Because of this, catalysts such as Prussian Blue analogues (PBA) have been receiving a lot of attention in recent years. In addition, working under neutral conditions allows us to take advantage of the modification of conductive polymeric 3D printed electrodes (3DPE) with Prussian Blue. Thus, we described in this work the development of the polymeric 3D printed electrodes modified by cobalt-Prussian Blue and their performance in the water oxidation process. The 3D printed electrodes modified with Co3[Co(CN)6]2 (Co-Co PBA) have a Tafel slope of 343 mV dec−1 while those modified with Co3[Fe(CN)6]2 (Co-Fe PBA) have a Tafel slope of 378 mV dec−1. This means that both catalysts have the same mechanism for the water oxidation process. On the other hand, the overpotential of Co-Co PBA in 3DPE is lower than the value observed by Co-Fe PBA in 3DPE suggesting the best electrocatalytic activity for Co-Co PBA catalyst.

Abstract The treatment of infections caused by resistant microorganisms represents a big challenge in healthcare due to limited treatment options. For this reason, the discovery of new active substances which are able to perform innovative and selective actions is of great impact nowadays. Statins and triazenes (TZC) have consolidated as a promising class of compounds, characterized by the expressive biological activity, especially antimicrobial activities. The aim of this study was to assess the in vitro synergistic antibacterial effect of the association of statins and a new TZC complex {[1-(4-bromophenyl)-3-phenyltriazene N 3-oxide-κ 2 N 1,O 4](dimethylbenzylamine-κ 2 C 1,N 4)palladium(II)} (Pd(DMBA)LBr) against American Type Culture Collection (ATCC) strains and clinical isolates. The complex and the statins showed bacterial activity of all tested strains and clinical isolates, evidencing that TZC complexion with metals can be promising. Simvastatin showed synergy when associated to the complex (FICI≤0.5), being the minimum inhibitory concentration (MIC) of 16 µg mL-1 found in 6 samples. Thus, it is possible to infer that the association between Pd(DMBA)LBr and simvastatin consists of an alternative to increase the pontential of these compounds, since statins have low toxicity.

Bacterial resistance to antibacterial agents is currently a major concern. We report the synthesis, in vitro antibacterial activity and toxicity toward Artemia salina of six diaryltriazene compounds bearing different substituent groups. Minimal Inhibitory Concentration (MIC) and Minimal Bactericidal Concentration (MBC) values against standard strains (ATCC) and clinical isolates (including ESBL, MBL and AmpC strains) were good to very good, in the range 8 to 128 mg mL-1. Results suggest that hydroxyl, 4-carboxyl and 4-phenyldiazenil groups attached to the diaryltriazenes provide enhanced activity. Toxicity results showed very low LC50 values for three compounds (10-fold lower than DTIC).