Di-aqua-bis-(nicotinamide-κN (1))bis-(thiocyanato-κS)cobalt(II).

In the title compound, [Co(NCS)2(C6H6N2O)2(H2O)2], the Co(II) cation is located on an inversion centre and is coordinated by two thio-cyanate anions, two nicotinamide mol-ecules and two water mol-ecules in a distorted N2O2S2 octa-hedral geometry. The amide group is twisted by 31.30 (16)° with respect to the pyridine ring. In the crystal, mol-ecules are linked by O-H⋯O, O-H⋯S and N-H⋯S hydrogen bonds into a three-dimensional supra-molecular network. Weak π-π stacking is observed between parallel pyridine rings of adjacent mol-ecules, the centroid-centroid distance being 3.8270 (19) Å.

Di-aqua-bis-(nicotinamide-κN (1))bis-(thio-cyanato-κN)nickel(II).

In the title complex, [Ni(NCS)2(C6H6N2O)2(H2O)2], the Ni(II) ion is located on an inversion center and is coordinated in a distorted octa-hedral environment by two N atoms from two nicotinamide ligands and two water mol-ecules in the equatorial plane, and two N atoms from two thio-cyanate anions in the axial positions, all acting as monodentate ligands. In the crystal, weak N-H⋯S hydrogen bonds between the amino groups and the thio-cyanate anions form an R 4 (2)(8) motif. The complex mol-ecules are linked by O-H⋯O, O-H⋯S, and N-H⋯S hydrogen bonds into a three-dimensional supra-molecular structure. Weak π-π inter-actions between the pyridine rings is also found [centroid-centroid distance = 3.8578 (14) Å].

Application of polymer nanocomposites in the nanomedicine landscape: envisaging strategies to combat implant associated infections.

This review article presents an overview of the potential biomedical application of polymer nanocomposites arising from different chemistries, compositions, and constructions. The interaction between the chosen matrix and the filler is of critical importance. The existing polymer used in the biomedical arena includes aliphatic polyesters such as polylactide (PLA), poly(ε-caprolactone) (PCL), poly(p-dioxanone) (PPDO), poly(butylenes succinate) (PBS), poly(hydroxyalkanoate)s, and natural biopolymers such as starch, cellulose, chitin, chitosan, lignin, and proteins. The nanosized fillers utilized to fabricate the nanocomposites are inorganic, organic, and metal particles such as clays, magnetites, hydroxyapatite, nanotubes chitin whiskers, lignin, cellulose, Au, Ag, Cu, etc. These nanomaterials are taking root in a variety of diverse healthcare applications in the sector of nanomedicine including the domain of medical implants and devices. Despite sterilization and aseptic procedures the use of these biomedical devices and prosthesis to improve the patient's 'quality of life' is facing a major impediment because of bacterial colonization causing nosocomial infection, together with the multi-drug-resistant 'super-bugs' posing a serious threat to its utility. This paper discusses the current efforts and key research challenges in the development of self-sterilizing nanocomposite biomaterials for potential application in this area.