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Five new complexes of the palladium(II) ion (C1-C5) having the general formula [(PdL 2 )]Cl 2 with some 2-aminothiazoles (L1-L5), where L1 = 2-amino-4-(3,4-difluorophenyl)thiazole, L2 = 2-amino-5-methyl-4-phenylthiazole, L3 = 2-amino-4-phenylthiazole, L4 = 2-amino-4-(4-chlorophenyl)thiazole, and L5 = 2-amino-4-(2,4-difluorophenyl)thiazole, have been synthesized and characterized by elemental microanalysis and infrared, 1 H NMR and 13 C NMR spectroscopy. The in vitro antimicrobial activity of the five ligands and the corresponding Pd(II) complexes is investigated. Testing is performed by the microdilution method and the minimum inhibitory concentration (MIC) and minimum microbicidal concentration (MMC) have been determined. Testing is conducted against 11 microorganisms (nine strains of pathogenic bacteria and two yeast species). The tested ligands and palladium(II) complexes show selective, high and moderate activity. There is a difference in antimicrobial activity between the ligands and the corresponding palladium(II) complexes. The complexes have significant anti-staphylococcal activity and activity on Pseudomonas aeruginosa which is better than the positive control. The interactions of newly synthesized palladium(II) complexes with calf thymus DNA (CT-DNA) were investigated using UV-Vis absorption and fluorescence spectroscopy. Analysis of UV-absorption and fluorescence spectra indicates the formation of a complex between the palladium(II) complexes and DNA. The high values of intrinsic binding constants, K b , of the order 10 4 M -1 and Stern-Volmer quenching constants, K SV indicated very good binding of all complexes to CT-DNA. Also, the new Pd(II) complexes show high cytotoxic activity towards the human prostate cancer cell line and insignificant activity towards non-cancerous human fibroblasts. Future research could additionally explore the biological activity of Pd(II) complexes presented in this paper and investigate the possibility of their implementation in clinical practice.5 M -1 indicated very good binding of all complexes to CT-DNA. Also, the new Pd(II) complexes show high cytotoxic activity towards the human prostate cancer cell line and insignificant activity towards non-cancerous human fibroblasts. Future research could additionally explore the biological activity of Pd(II) complexes presented in this paper and investigate the possibility of their implementation in clinical practice.

In this paper, Cu(II), Mn(II) and Zn(II) complexes with N , N , N -trimethyl-2-oxo-2-(2-(1-(thiazol-2-yl)ethylidene)hydrazinyl)ethan-1-aminium chloride (HL1Cl) were synthesized and characterized by single-crystal X-ray diffraction, IR spectroscopy, elemental analysis and DFT calculations. In all three complexes, a ligand (L1) is coordinated in a deprotonated formally neutral zwitterionic form via NNO donor set atoms. Cu(II) and Zn(II) form mononuclear penta-coordinated complexes [CuL1(N 3 )(CH 3 OH)]BF 4 and [ZnL1(N 3 ) 2 ], respectively, while Mn(II) forms a binuclear [Mn 2 L1 2 (μ- 1,1 -N 3 ) 2 (N 3 ) 2 ]·2CH 3 OH complex, with unusual distorted trigonal-prismatic geometry around the metal centers. The antimicrobial activity of these complexes was tested against a panel of Gram-negative and Gram-positive bacteria, two yeasts and one fungal strain. The binuclear Mn(II) complex showed antifungal activity of similar intensity to amphotericin B. Based on the results of the brine shrimp test and DPPH radical scavenging activity, the most active Cu(II) and Mn(II) complexes were selected for evaluation of cytotoxic activity against five malignant cancer cell lines (HeLa, A375, MCF7, PC-3 and A549) and one normal cell line HaCaT. Both complexes showed significant activity. It should be pointed out that the activity of the Mn(II) complex against the MCF7 breast cancer cell line is only slightly weaker than that of cisplatin, but with selectivity to the tumor cell line in comparison to normal HaCaT cells, which is non-existent in the case of cisplatin.

Antimicrobial materials are expected to be alternatives for antibiotics against multidrug-resistant bacteria. In this paper, non-spherical α-Fe 2 O 3 @Au/PDA core/shell nanoparticles with tunable shapes are synthesized by a one-step in situ oxidation-redox polymerization method toward near infrared light-responsive antibacterial therapy. The thickness and composition of the Au/PDA hybrid shell can be controlled by varying the concentration of HAuCl 4 and the dopamine precursor. Owing to the wonderful photothermal characteristics originating from the Au/PDA shell, the spindle α-Fe 2 O 3 @Au/PDA core shell nanoparticles exhibit excellent photothermal sterilization effects against both Escherichia coli and Staphylococcus aureus at low concentrations. Meanwhile, the NIR photothermal induced bactericidal performance indicates that α-Fe 2 O 3 @Au/PDA hybrid particles with tunable non-spherical shapes possess unique controllable antibacterial effects. As a result, this finding provides a simple strategy for fabricating high performance photothermal antibacterial agents and the final products possess high potential in synergistic antimicrobial therapy.

The survival of all urease and/or hydrogenase containing pathogens depends on the proper homeostasis of nickel. In the scope of this perspectives paper, details of Ni(2+) metabolism of Helicobacter pylori, a widespread stomach-ulcer causing bacterium, are described. Nickel binding proteins and thermodynamics of such metal complexes are discussed in detail and special focus is given to potential nickel binding sequences in this metal's chaperones and regulators. A list of potential Ni(2+) binding sites in various pathogens is presented, which points out numerous examples of nickel interactions that still need to be understood.

The green synthesis of supported noble metal nanoparticles is now the most exciting field for various catalytic applications as well as biomedical applications. In this paper we report a novel synthesis method of a polymer consisting of silver nanoparticles (AgNPs) using immobilized microorganisms in alginate beads. Microorganisms present in the polymer reduce aqueous AgNO3 to AgNPs which get trapped in the polymer to form Ag-Alginate (Ag-Alg) biohydrogel. The formed biohydrogel was characterized by UV-visible (UV-Vis) spectroscopy, dynamic light scattering (DLS) spectroscopy, X-ray diffraction (XRD), Fourier transform infrared (FT-IR) spectroscopy, scanning electron microscopy (SEM), energy dispersive X-ray (EDS), transmission electron microscopy (TEM), and selected area electron diffraction (SAED) analysis. TEM analysis showed that less than 15 nm AgNPs formed in the polymer. The Ag-Alg biohydrogel exhibited efficient heterogeneous catalytic activity in the reduction of 4-nitrophenol to 4-aminophenol in the presence of NaBH4 in aqueous solution with durable reusability. Also this biohydrogel showed excellent antimicrobial activity against pathogenic bacteria (antibiotic resistant) and fungi. The described synthesis method of Ag-Alg biohydrogel can be considered robust, cost effective and eco-friendly. The formed highly catalytic active biohydrogel can be used as catalyst in industries and drinking water purification.

Polyaniline/Cu(0.05)Zn(0.95)O (PANI/CZO) nanocomposites were prepared by in situ inverse microemulsion method. Based on the characterization of the crystal structure, chemical composition, and morphology of the samples, it was confirmed that CZO nanoparticles were incorporated into the polyaniline matrix. Studies of the antimicrobial activities of the samples against Staphylococcus aureus, Escherichia coli and Candida albicans were carried out using powder inhibition zone, minimum inhibitory concentration and minimal bactericidal concentrations methods. The results showed clearly that, as an antibacterial agent, PANI/CZO nanocomposites exhibited excellent antibacterial activity against the growth of microorganisms. Furthermore, the antibacterial mechanism of the samples was also deduced in this paper.