Synthesis, structure, and antimicrobial properties of mixed-metal organometallic polyoxometalates [Cp*2M5VO17]− (M = Mo, W)

Polyoxometalates and their composites for antimicrobial applications: Advances, mechanisms and future prospects

The overuse of antibiotics can lead to the development of antibiotic-resistant bacteria, which can be even more difficult to treat and pose an even greater threat to public health. In order to address the issue of antibiotic-resistant bacteria, researchers currently are exploring alternative methods of sterilization that are both effective and sustainable. Polyoxometalates (POMs), as emerging transition metal oxide compounds, exhibit significant potential in various applications due to their remarkable tunable physical and chemical performance, especially in antibacterial fields. They constitute a diverse family of inorganic clusters, characterized by a wide array of composition, structures and charges. Presently, several studies indicated that POM-based composites have garnered extensive attention in the realms of the antibacterial field and may become promising materials for future medical applications. Moreover, this review will focus on exploring the antibacterial properties and mechanisms of different kinds of organic-inorganic hybrid POMs, POM-based composites, films and hydrogels with substantial bioactivity, while POM-based composites have the dual advantages of POMs and other materials. Additionally, the potential antimicrobial mechanisms have also been discussed, mainly encompassing cell wall/membrane disruption, intracellular material leakage, heightened intracellular reactive oxygen species (ROS) levels, and depletion of glutathione (GSH). These findings open up exciting possibilities for POMs as exemplary materials in the antibacterial arena and expand their prospective applications.

Synthesis and characterization of Anderson-Evans type polyoxometalates, antibacterial properties

In the present work, the new aluminium-substituted polyoxometalates of the Anderson-Evans type have been prepared and structurally defined by the reaction of aluminium (III) chloride hexahydrate and sodium tungstate dihydrate/sodium molybdate dihydrate in an aqueous basic medium. Elemental analysis, FT-IR, TGA, 1H NMR, and 31P NMR analysis revealed that these polyoxometalates had the following formula: [Ph4P]3[Al(OH)6Mo6O18]·4H2O 1, [Ph4P]3[Al(OH)6W6O18]·4H2O 2, [C7H10N]3[Al(OH)6Mo6O18]·4H2O 3, [C7H10N]3[Al(OH)6W6O18]·4H2O 4. The compounds 1 and 2 show promising antibacterial activity against gram-positive Staphylcoccus aureus ATCC 25923 and gram-negative Escherichia coli ATCC 25922 bacteria.