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A binder is an important component in lithium-ion batteries and plays a significant role in maintaining the properties of active substances. Most studies in the field of binders have only focussed on physical properties such as bonding performance. Here, a polyacrylic acid-modified binder was designed and adapted to Li[Ni 0.8 Co 0.1 Mn 0.1 ]O 2 , which enhanced the electrochemical stability of Li[Ni 0.8 Co 0.1 Mn 0.1 ]O 2 from 30.2 to 66.6% (300 cycles at 1 C). We for the first time discovered that this was caused by a chemical reaction between polyacrylic acid and the residual lithium on the surface during the cycling, which formed a lithium propionic acid coating layer and maintained the stability of the layered structure.

The interaction of DNR-D3 (daunorubicin derivative) synthesized in our laboratory with ctDNA was investigated by UV spectrum and fluorescence spectrum under physiological conditions (pH 7.4) for the first time. The red shifts and hypochromicities were observed from the absorption titration experiments. These results suggest that DNR-D3 was intercalated into the DNA base pairs. Through the fluorescence quenching data measured at different temperatures (20 degrees C, 30 degrees C and 37 degrees C), it is known that the quenching mechanism of fluorescence of DNR-D3 by ctDNA is a static quenching type. On the other hand, the binding constant, the number of binding sites and thermodynamic parameters were also obtained. These data also indicate that the binding mode of the interaction between DNR-D3 and ctDNA is intercalation. Additionally, the types of interaction force are mainly hydrogen bonding and electrostatic interaction, and the binding is exothermic enthalpy-entropy cooperative driven process. When the degree of fluorescence quenching of DNR-D3 is 50%, the ratio of the molar concentration of DNR-D3 to ctDNA is 7/25, which indicates that the DNR-D3 anthracycline was intercalated into the DNA base pairs and that DNR-D3 showed a strong anti-cancer activity. DNR-D3 is expected to become one of the drug candidates from our investigations.

The interaction between norfloxacin (NRF) and ovalbumin (OVA) was studied by fluorescence and absorption spectroscopy. The binding constants and the binding sites were measured by fluorescence quenching method. It was found that the emission peak of OVA was positioned at 338 nm. When the norfloxacin was added into OVA solution gradually, the intensity of 338 nm emission peak of OVA decreased obviously and moved towards long wavelength. The experiment demonstrated that the higher the temperature, the lower the slopes of quenching curves of OVA in the presence of different amounts of NRF. It was confirmed that the combination of NRF with OVA is a single static quenching process. With the increase in the pH of the solution, the quenching efficiency decreased in the binding. From thermodynamic parameters, it can be judged that the binding power between OVA and NRF is electrostatic effect and H-bond formation. The UV-Vis absorption spectra of OVA in the presence of NRF show that the conformation of OVA changed.

Protein is one of the most important living matters, and researches relatedto it have interested so many scientific workers. The secondary structure of protein plays a crucial role in maintaining protein's physiological activity. With the development of technology and the improvement of research technique, there are more and more in-depth studies on protein's microstructure. In recent years, many research works in this field have been done with different kinds of physical and chemical methods and Fourier transform infrared spectroscopy(FTIR)holds an unshaken position due to its unique superiority. The present paper is a general review of the related studies all over the world, and the assignments of the major infrared absorption bands of denaturized protein are introduced, and the spectroscopic features and the analytical methods are mainly reviewed.