The biomolecular binding behavior of anticancer drug dacarbazine (DTIC) in the presence of titanium dioxide (TiO2) nanoparticle interface has been studied by using electrochemical methods. The results indicate that the presence of TiO2 nanoparticles can obviously increase the binding affinity of DTIC to DNA or DNA bases and significantly enhance the detection sensitivity for the relative biomolecular recognition.

The effect of fl-cyclodextrin (fl-CD) on the spectral properties of quinine molecules has been specifically studied by absorption/fluorescence and Fourier transform infrared (FTIR) spectroscopy. In particular, FTIR studies of the complexation of aqueous quinine hydrochloride with fl-CD provide fresh insight into the molecular structure of the complex and reveal some important information in relation to the molecular interactions of the cyclodextrin complex system. Nuclear magnetic resonance data support the inclusion conformation of the interaction sites and the presence of hydrogen bonds which stabilize the complexes.

We report a novel approach to enhance the efficient accumulation and utilization of anticancer drug daunorubicin on cancer cells through the combination with CdS nanoparticles. Our observations using confocal fluorescence scanning microscopy as well as electrochemical analysis methods demonstrate that CdS nanoparticles can readily bind with daunorubicin on the external membrane of the targeted cells and facilitate the uptake of drug molecules in the human leukemia K562 cells. Besides, our results also indicate that the competitive binding of CdS nanoparticles with accompanying anticancer drug to the membrane of leukemia K562 cells could efficiently prevent the drug release by the drug-sensitive and drug-resistant leukemia cells and thus inhibit the possible multidrug resistance of cancer cells, which could be further utilized to improve the future drug efficiency in respective tumor chemotherapies.

The electrochemical redox-induced contact angle changes of hemoglobin droplets in the absence and presence of tetraheptylammonium-capped Fe3O4 nanoparticles have been explored by using in situ electrochemical contact angle measurements. The results indicate that the electrochemical redox process may lead to some structure changes of hemoglobin (Hb), which could further induce the hydrophobic-to-hydrophilic changes of the relative droplets. Our observations demonstrate that hemoglobin could self-assemble on the surface of the functionalized Fe3O4 nanoparticles as Hb–Fe3O4 nanocomposites, which may contribute to much more significant change of the electrochemical redox-induced contact angle values than that with free nano-Fe3O4. These results suggest that in situ electrochemical contact angle measurements could be readily applied as a new and convenient method to detect some specific biological process.

The binding behavior of several fluorescence dyes to calf thymus DNA has been studied by absorption, fluorescence and atomic force microscopy (AFM), which could provide direct evidence of formation modes and the corresponding nanostructural features of the ligand-DNA complexes.