Antimicrobial Activity of Polyoxometalate Ionic Liquids against Clinically Relevant Pathogens

Abstract

The activity of a new class of antimicrobials—polyoxometalate ionic liquids (POM‐ILs)—is systematically investigated. The prototype POM‐ILs feature Keggin‐type anions (α‐SiW11O398−) and tetraalkylammonium ions as active cationic species. Antimicrobial tests of the POM‐ILs against important human pathogens show that variation of the alkyl chain length of the cation leads to significant changes in antimicrobial activity against the medically relevant Gram‐negative bacteria Escherichia coli and Pseudomonas aeruginosa, and especially against the Gram‐positive Staphylococcus aureus. Owing to the unique materials properties of the POM‐ILs, such as high viscosity and water immiscibility, applications of antimicrobial surface coatings against airborne pathogens or for water decontamination can be envisaged. Furthermore, the combination of antimicrobially active cations with POM anions might afford new POM‐ILs with two active components.

Water Purification and Microplastics Removal Using Magnetic Polyoxometalate‐Supported Ionic Liquid Phases (magPOM‐SILPs)

“…In sum, PS microplastics removal by magnetic particle attachment could provide ameans of treating larger volumes of water which are not amenable to classical filtration. [21] Some of our previous research has confirmed the bactericidal properties of POM-ILs, [10,12,25] therefore we hypothesized that magPOM-SILP 2 would be able to purify water heavily contaminated with bacteria. Thea ntibacterial water purification properties of the magPOM-SILPs were tested against gram-negative E. coli and gram-positive B. subtilis.…”

“…Thea ntibacterial water purification properties of the magPOM-SILPs were tested against gram-negative E. coli and gram-positive B. subtilis. [12] Briefly,aqueous solutions of the microporous magPOM-SILP 2 were inoculated with 10 6 CFU mL À1 of E. coli or B. subtilis and incubated at 37 8 8Cf or 1hbefore removing the particles with am agnet and quantifying the bacteria present in the supernatant solutions.AtamagPOM-SILP 2 concentration of 1mgmL À1 ,t he bacterial removal was 58 %f or E. coli and 100 %f or B. subtilis,w hile at ac oncentration of 10 mg mL À1 the bacterial removal efficiency was 100 %for both bacterial strains.T he antibacterial effect was confirmed and characterized using electron microscopies (SEM and TEM). Ther eusability of the magPOM-SLIP nanoparticles was tested over three cycles of inoculation with E. coli or B. subtilis,p article separation, and particle washing with water and subsequent reuse with af resh inoculum of the bacteria.…”

“…TheP OM-IL is synthesized as described in the literature [10,12,24,25] by combination of the lacunary-Keggin cluster anion ([a-SiW 11 O 39 ] 8À ) [26] and the antimicrobial tetra-n-heptyl ammonium cation (Q 7 (= (n-C 7 H 15 ) 4 N + ) [27] (Figure 1). The magPOM-SILPs were prepared by dispersing SiO 2 @Fe 3 O 4 particles (4.0 g) in aP OM-IL solution in acetone (50 mL, [POM-IL] = 3.36 mm, m(POM-IL = 1.0 g) and subsequent vacuum drying, giving the composite magPOM-SILP 2 with aP OM-IL loading of 20 wt %, see Supporting Information for details.A saresult of the partial filling of the pores in 2 with the POM-IL, the BET specific surface area of 2 was reduced to around 100 m 2 g À1 and the BJH pore volume was 0.70 cm 3 g À1 ;for further characterization details,see Support-ing Information.…”

Mukaiyama‐Preis: F. Glorius und Y. Nakao Wissenschaftspreis der Stadt Ulm: C. Streb BioTrans‐Senior‐Preis: M. T. Reetz BioTrans‐Junior‐Preis: F. Hollmann

“…Sein Forschungsinteresse gilt der Chemie der Polyoxometallate und ihrem Einbau in funktionelle Komposite für Katalysezwecke, der Sonnenenergiekonversion, der elektrochemischen Energiespeicherung und fortschrittlichen multifunktionellen Materialien. In der Angewandten Chemie hat er Polyoxometallat‐Nickelschaum‐Elektroden beschrieben und in ChemPlusChem die antimikrobielle Aktivität von organischen Flüssigkeiten auf Polyoxometallatbasis …”

Nanocomposites of Polyoxometalates and Chitosan‐Based Polymers as Tuneable Anticancer Agents

“…Over the last decades, POMs were proposed as promising candidates for new antidiabetic, anti‐Alzheimer, anticancer and antiviral drugs. They were identified as antibacterial agents, either in pure form, as ionic liquid or in association with commercial antibiotics …”