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Nanocomposite sol comprised of hydroxyapatite (HA) and silk fibroin (SF) was synthesized via a wet-mechanochemical route. SF particles were chemically modified using an alkali solution attempting to disentangle their surface fibrils so as to enhance the effective contact between the mineral and the organic particles. With the alkali pretreated SF involved, Vickers microhardness of the composite increases by 57% and a more enhanced three-dimensional porous network with a homogenous particle form and a uniform pore size distribution is formed through the intimate crosslinkage between HA clusters and SF fibrils. In addition, the alkali pretreatment of SF not only increased the viscosity and the rigidity of the composite sol, but also promotes its gelation process, which is favorable for healing bone defects by an injection technique.

Four copper(I) complexes of 2,11-dithia[3.3]paracyclophane (dtpcp), [CuI(dtpcp)] · MeCN (1), [CuBr(dtpcp)] · MeCN (2), [CuCl(dtpcp)] · MeCN (3) and [Cu2I2(dtpcp)2] · Me-thf (4) (Me-thf=2-methyltetrahydrofuran), have been synthesized and their molecular structures determined by X-ray crystallography. Complexes 1 and 2 are isostructural, and exhibit 3D networks with elliptical channels along a-axis, which are constructed by dtpcp molecules bridging zigzag CuI and CuBr chains, respectively. Complexes 3 and 4 are 2D porous sheet networks constructed by bridging the zigzag copper-dtpcp chains via rhombic ring of Cu2X2 (X=Cl or I). All sheets in 3 are packed in an eclipsed manner through π–π stackings to generate channels along the a-axis. However, the 2D porous sheets in 4 are packed in an offset mode such that channels are not formed along c-axis. Complexes 1 and 2 can reversibly incorporate guest acetonitriles without collapse of structures, and the original frameworks of 1 and 2 are completely recovered after incorporation of guests which are confirmed by X-ray powder diffraction (XRPD) pattern and 1H NMR spectrum. Additionally, complex 1 exhibits selectivity in size and polarity for guest inclusion.

A new type of silver(I) coordination complex derived from silver(I) perchlorate (or triflate) and polycyclic aromatic compounds is reviewed. Structural studies by single-crystal X-ray diffraction have shown that all compounds contain extended one- to three-dimensional structures in which several metal atoms are sandwiched between two fused polycyclic systems. Special attention is paid to the combination of the plasticity of the metal ion, coordinative versatility of the aromatic ligand, solvent effect and the nature of the counteranions for designing metal complexes with a wide range of infinite frameworks.