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Nanomaterials based on metal–doped fluorapatite (FAP) have attracted considerable interest as potential next–generation antimicrobial agents. In this study, Cu2+–doped FAP nanocrystals have been successfully synthesized by a neutralization method at room temperature. Their structural, optical, antimicrobial, and hemcompatible properties have been investigated. XRD, FTIR, FESEM, and N2 adsorption–desorption studies indicate the formation of single–phase FAP mesoporous nanopowders, composed of rod–like particles. TEM images confirmed the formation of nanorodes with a length of 60 nm and a width of about 18 nm. Rietveld analysis shows that the Cu2+ ions preferentially substitute Ca2 (6 h) sites in the hexagonal fluorapatite crystal structure. Fluorescence spectroscopy accompanied by MCR–ALS method confirms substitution of Cu2+ ions in FAP crystal lattice with extracting additional d–d band transition at green color from FAP broadband self–activated luminescence in violet–blue color. Antimicrobial studies conducted on Staphylococcus aureus, Escherichia coli and Micrococcus lysodeikticus showed that FAP nanopowder with the highest Cu2+ content have strong bacteriostatic action on Staphylococcus aureus bacterial strain in mediums containing nutrition matters. In addition, this sample in comparison to pure FAP achieved a high percentage of relative reduction of bacterial population for all three species, being >90% in most cases. Fungistatic action is noticed too, throwgh the slowing down mycelium growth of fungus Aspergillus niger, Aspergillus flavus and Penicillium roqueforti and reduction of sporulation of Aspergillus niger species. Cu2+–doped FAP nanocrystals shows a synergistic antimicrobial effect with Cu2+ and F− ions. Concerning the potential biomedical applications, the hemolysis ratios of the Cu2+–doped FAP samples were below 5%. The obtained results pointed out the possible use of the synthesized nanocrystals as broad–spectrum antimicrobial agents for various

In vitro cytotoxic evaluation, formation constants and thermal stability of four mixed-ligand Co(II) complexes with tpmc = N,N',N",N'"-tetrakis(2-pyridylmethyl)-1,4,8,11-tetraazacyclotetradecane and carboxylate/dicarboxylate co-ligands of formulas [Co2(benz)2tpmc](ClO4)2•3H2O (1), benz– = benzoate anion; [Co2(L)tpmc](ClO4)2•nH2O, L = pht2– (phthalate dianion), n=2 (2), L = ipht2– (isophthalate dianion), n=4 (3) and L = tpht2–(terephthalate dianion), n=4 (4) are reported. The stoichiometric composition of the compounds in the solution were determined spectrophotometrically using Job's methods. Formation constants, K and Gibbs free energy, ΔG values were calculated. The thermal behavior of the complexes was investigated by simultaneous TG/DSC and TG – MS measurements. The cytotoxic effect of the complexes, the free ligands, the DMSO solvent and cis-platin, as referent cytostatic drug, was evaluated on Human cervix adenocarcinoma (HeLa), human melanoma (Fem-x) and human colon carcinoma (LS174) cell lines. The IC50 values were between 12.7–42.3 μM. The first crystal structure determination of the Co(II) complex [Co2(µ-pht)tpmc](ClO4)2•H2O with boat conformation of tpmc ligand, was also done. The complex crystallizes in monoclinic crystal system, C2/c space group. The geometries around both Co(II) atoms are highly distorted octahedral. The Co(II) ions exhibit CoN4O2 coordination environments with the four nitrogen donor atoms of the tpmc ligand and two oxygen atoms belonging to the one carboxylate group of pht2− ligand. The carboxylate groups of pht2− are coordinated in an endo-bidentate mode. The tpmc ligand adopted a boat conformation in which the two coordinated Co(II) atoms are located on the same side of the ring, with Co•••Co distance amounting 5.4799(5) Å.