Investigation of binding interactions between BSA and [EPMpyr][Sal] through spectroscopy studies, thermophysical and thermodynamic properties

Enhancement of thioethers removal by pre-oxidation-coagulation: Effects of background organic matter

Swampy/septic odor caused by thioethers has become the main taste and odor (T&O) problem in drinking water of China. Improving its removal performance by commonly traditional water treatment process is significant. In our study, we have found that pre-oxidation could modify the background dissolved organic matter (DOM) properties and thus improve the coagulation performance of thioethers, increasing the coagulation removal rates by 1.5-3 times. Particularly, after pre-ozonation only protein-like substances remained, and thioethers removal was 1.5 times higher than that after pre-chlorination (only coagulation not including oxidation). Compared with humic acid (HA), the thioethers compounds removal efficiencies under bovine serum albumin (BSA) as background DOM was increased by 0.3-3 times. Through Freundlich model analysis, the binding strength of BSA (K_F = 20.712, at 298 K) to dimethyl disulfide (DMDS) was enhanced by 60 % compared to HA (K_F = 12.778, at 298 K). According to thermodynamic parameters, the binding effect between HA/BSA and thioethers compounds was mainly van der Waals forces and hydrogen bond. BSA with more amino structure and oxygen groups was more easily to adsorb DMDS through hydrogen bond and thus achieved better coagulation performance. Therefore, pre-ozonation combined with coagulation was suggested to be more suitable for thioethers compounds control.

An Overview on the Recent Advances in Alternative Solvents as Stabilizers of Proteins and Enzymes

Currently, the use of alternative solvents is increasing, namely ionic liquids (ILs) and deep eutectic solvents (DESs) in diverse fields of knowledge, such as biochemistry, chemistry, chemical engineering, biotechnology and biomedicine. Particularly, when compared to traditional solvents, these alternative solvents have great importance for biomolecules due to the enhanced solubility, structure stability and the biological activity of biomolecules, such as protein and enzymes. Thus, in this review article, the recent developments and efforts on the technological developments carried out with ILs and DESs for the stabilization and activation of proteins and enzymes are provided. The most studied IL- and DES-based formulations for proteins and enzymes are discussed and the molecular mechanisms and interactions related to the increased stability promoted by these alternative solvents are disclosed, while emphasizing their main advantages.

Recent Advances in Ionic Liquids in Biomedicine

The use of ionic liquids and deep eutectic solvents in biomedical applications has grown dramatically in recent years due to their unique properties and their inherent tunability. This review will introduce ionic liquids and deep eutectics and discuss their biomedical applications, namely solubilization of drugs, creation of active pharmaceutical ingredients, delivery of pharmaceuticals through biological barriers, stabilization of proteins and other nucleic acids, antibacterial agents, and development of new biosensors. Current challenges and future outlooks are discussed, including biocompatibility, the potential impact of the presence of impurities, and the importance of understanding the microscopic interactions in ionic liquids in order to design task-specific solvents.

The synthesis, characterization, DNA/BSA/HSA interactions, molecular modeling, antibacterial properties, and in vitro cytotoxic activities of novel parent and niosome nano-encapsulated Ho(iii) complexes

Based on the importance of metal-centered complexes that can interact with DNA, this research focused on the synthesis of a new Ho(iii) complex. This complex was isolated and characterized via elemental analysis, and FT-IR, fluorescence, and UV-vis spectroscopy. Additional confirmation of the Ho(iii) complex structure was obtained via single-crystal X-ray diffraction. DNA interaction studies were carried out via circular dichroism (CD) spectroscopy, UV-vis absorption spectroscopy, viscosity measurements and emission spectroscopy; it was proposed that the metal complex acts as an effective DNA binder based on studies in the presence of fish DNA (FS-DNA), showing high binding affinity to DNA in the presence of hydrophobic and electron donating substituents. Also, the interactions of this complex with human (HSA) and bovine serum albumin (BSA) proteins were studied via fluorescence spectroscopy techniques and the obtained results reveal an excellent propensity for binding in both cases. Furthermore, the interactions of the Ho(iii) complex with DNA, BSA and HSA were confirmed via molecular docking analysis. The antimicrobial activities of the Ho(iii) complex were tested against Gram-negative bacteria and Gram-positive bacteria. In addition, a niosome nano-encapsulated Ho(iii) complex was synthesized, and the parent and encapsulated complexes were evaluated as potential antitumor candidates. The main structure of the Ho(iii) complex is maintained after encapsulation using niosome nanoparticles. The MTT method was used to assess the anticancer properties of the Ho(iii) complex and its encapsulated form toward human lung carcinoma and breast cancer cell lines. The anticancer activity in the encapsulated form was more than that of the parent Ho(iii) complex. In conclusion, these compounds could be considered as new antitumor candidates.