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An arginine substituted zinc phthalocyanine (ArgZnPc) which is capable of disaggregating at high concentrations in polar non aqueous solvents through concentration-driven hydrogen bond type transformation has been prepared. The ArgZnPc was prepared through a "guanidine meditated self-catalytic ester hydrolysis" reaction. The concentration-driven disaggregation of ArgZnPc was confirmed by UV-Vis absorption spectra, fluoresce emission spectra and lifetimes, and singlet oxygen quantum yields data. This result provides a new way for the disaggregation of aromatic compounds at high concentrations.

The interaction between the photosensitive antitumour drug, 2(3),9(10),16(17),23(24)-tetra-(((2-aminoethylamino)methyl)phenoxy)phthalocyaninato-zinc(II) (ZnPc) and bovine serum albumin (BSA) has been investigated using various spectroscopic methods. This work may provide some useful information for understanding the interaction mechanism of anticancer drug–albumin binding and gain insight into the biological activity and metabolism of the drug in blood. Based on analysis of the fluorescence spectra, ZnPc could quench the intrinsic fluorescence of BSA and the quenching mechanism was static by forming a ground state complex. Meanwhile, the Stern–Volmer quenching constant (KSV), binding constant (Kb), number of binding sites (n) and thermodynamic parameters were obtained. Results showed that the interaction of ZnPc with BSA occurred spontaneously via hydrogen bond and van der Waal's force. According to Foster's non-radioactive energy transfer theory, the energy transfer from BSA to ZnPc occurred with high possibility. Synchronous fluorescence and circular dichroism (CD) spectra also demonstrated that ZnPc induced the secondary structure of and conformation changes in BSA, especially α helix. Copyright © 2015 John Wiley & Sons, Ltd.

A new docetaxel (DTX) delivery system has been prepared based on calcium phosphate nanoparticles (CaP NPs) and obtained DTX-adsorbed CaP NPs. The DTX-adsorbed CaP NPs were nearly spherical with mean diameter about 200 nm and a negative zeta potential of −18.8 ± 0.5 mV. They can be well dispersed and stable in water for a long time. In addition, the DTX-adsorbed CaP NPs showed higher cytotoxicity in human nonsmall-cell lung cancer (NSCLC) cell lines than that of DTX at the same experimental conditions. Thus, it could be concluded that CaP NPs can be a promising DTX delivery vehicle in NSCLC chemotherapy.

Controlled drug release systems can enhance the safety and availability but avoid the side effect of drugs. Herein, the concept of DNA complementary base pairing rules in biology is used to design and prepare a photothermal-triggered drug release system. Adenine (A) modified polydopamine nanoparticles (A-PDA, photothermal reagent) can effectively bind with thymine (T) modified Zinc phthalocyanine (T-ZnPc, photosensitizer) forming A-PDA = T-ZnPc (PATP) complex based on A = T complementary base pairing rules. Similar to DNA, whose base pairing in double strands will break by heating, T-ZnPc can be effectively released from A-PDA after near infrared irradiation-triggered light-thermal conversion to obtain satisfactory photodynamic-photothermal synergistic tumor treatment. In addition, PDA can carry abundant Gd3+ to provide magnetic resonance imaging guided delivery and theranostic function.

The doping of titanium dioxide (TiO2) with various metal or nonmetal elements has been considered as an effective strategy to extend the photoactive wavelength region to visible light. In this paper (nitrogen [N] and sulfur [S])-codoped anatase TiO2 nanoparticles were prepared via a sol–gel route, followed by a heat treatment at elevated temperatures. The as-prepared samples were extensively characterized by X-ray diffraction, UV–Vis absorption spectroscopy, and X-ray photoelectron spectroscopy. The N, S-codoped TiO2 nanoparticles showed a strong visible light absorption and exhibited an enhanced photocatalytic activity for the degradation of methylene blue as compared with the pure, N- or S-doped TiO2 under either UV light or solar light irradiation.

(Copper, Nitrogen)-codoped titanium dioxide (TiO2) nanoparticles have been prepared via a sol–gel route, followed by heat treatment at an elevated temperature. Such (Cu, N)-codoped TiO2 nanoparticles showed a strong absorption in the visible region and a red shift in the band gap transition and exhibited an enhanced photocatalytic activity as compared with the pure, N-doped and Cu-doped TiO2 for xylenol orange decomposition.