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Additions to the popular evaporation rate determination laboratory of alcohol-based hand-rub sanitizers are described here. Significantly, inquiry-driven protocols for formulating hand-rub sanitizers, falling-ball viscometry, and sanitizer efficacy are included. Incorporation of familiar substances ("molecular relevance") enables students to assimilate knowledge and connect to and recognize interrelated disciplines. To stimulate engagement and project ownership, students were given the opportunity to alter sanitizer formulations by varying the amount and molecular weight of the gelling agent. Viscosities were determined using a falling-ball viscometer to integrate physics and fluid dynamics concepts into these experiments. Lastly, to stress microbiological applications and determine the efficacy of their hand sanitizers, students tested the formulated hand sanitizers for qualitative efficacy using agar plating of skin secretions and comparing colonies formed from sanitized versus nonsanitized hands. Chemistry students with diverse interests recognized links across disciplinary boundaries (e.g., increased their awareness of physical properties of hand sanitizers and the relationship of molecular-scale phenomena to these properties). This three-hour laboratory provides an interdisciplinary supplement directly designed for freshman chemistry and engineering chemistry undergraduates and increases integration among biology, chemistry, engineering, and physics.

Glyphosate (N-(phosphonomethyl)glycine) is the most widely used herbicide on earth. A simple assay to quantify glyphosate concentrations in environmental samples was developed as part of an interdisciplinary effort linking introductory laboratory courses in chemistry, biology, and microbiology. In this 3 h laboratory experiment, students used UV-vis spectroscopy to quantify glyphosate in prepared unknowns and supernatants from glyphosate-treated soil samples. Regression analysis indicated that the assay is linear up to 20.0 ppm, making it particularly useful for detection of low levels of glyphosate in environmental samples. The assay can be used to quantify the activity of glyphosate-degrading soil microorganisms by comparing glyphosate levels between autoclaved and nonautoclaved soil slurries.

Glyphosate (N-(phosphonomethyl)glycine) is the most widely used herbicide on earth. A simple assay to quantify glyphosate concentrations in environmental samples was developed as part of an interdisciplinary effort linking introductory laboratory courses in chemistry, biology, and microbiology. In this 3 h laboratory experiment, students used UV-vis spectroscopy to quantify glyphosate in prepared unknowns and supernatants from glyphosate-treated soil samples. Regression analysis indicated that the assay is linear up to 20.0 ppm, making it particularly useful for detection of low levels of glyphosate in environmental samples. The assay can be used to quantify the activity of glyphosate-degrading soil microorganisms by comparing glyphosate levels between autoclaved and nonautoclaved soil slurries. [ABSTRACT FROM AUTHOR]

Four uranyl peroxide compounds with novel structures were formed following the dissolution of studtite, [(UO 2 )(O 2 )(H 2 O) 2 ](H 2 O) 2 , in imidazolium-based ionic liquids. The compounds were characterized using single crystal X-ray diffraction (SCXRD), powder X-ray diffraction (PXRD), Raman and infrared (IR) spectroscopy, and scanning electron microscopy (SEM) with energy-dispersive X-ray spectroscopy (EDS). The ionic liquids used in the experiments were 1-ethyl-3-methylimidazolium (EMIm) diethyl phosphate, EMIm ethyl sulfate, and EMIm acetate. Each of the four uranyl peroxide compounds contain components from the ionic liquids as terminal ligands on uranyl peroxide molecular units, bridging ligands in uranyl peroxide sheet structures, or charge balancing cations located in the interstitial space. The studtite dissolved in and reacted with the ionic liquids, producing unique crystal structures depending on the anionic component of the ionic liquid, the temperature at which the synthesis was performed, and the introduction of additional ionic species into the solution. This is the first report of studtite dissolving in and reacting with ionic liquids to form uranyl peroxide compounds, which has the potential to vastly increase the number of synthetic routes for the formation of uranyl peroxide clusters and uranyl peroxide cage clusters.

The assembly of molybdenum polyoxometalates (POMs) has afforded large discrete nanoclusters with varied degrees of reduction such as the ~20 % reduced molybdenum blues. While many heterometals have been incorporated into these clusters to afford new properties, uranium has yet to be reported. Here we report the first uranium containing molybdenum blue clusters and the unique properties exhibited by this incorporation. The uranyl ion (UO 2 2+ ) directs formation of Mo 72 U 8 , a square POM comprised of two faces connected by eight edge-sharing molybdenum dimers. Mo 72 U 8 , a chiral cluster, crystallizes as a racemic mixture and, in the solid state, has a 'negative' charge localized on one face of the cluster opposite the 'positively' charged face of another cluster. Using U(IV) as both heterometal and molybdenum reductant afforded crystals of Mo 97 U 10 , a wheel cluster with a heptamolybdate cap on one face. Mo 97 U 10 dissociates in solution, losing the heptamolybdate, to form Mo 90 U 10 . Using more solvent during synthesis afforded crystals of Mo 90 U 10 S 4 which, instead of heptamolybdate, contains four sulfate ions. Crystals of Mo 90 U 10 S 4 undergo a dehydration induced phase change where clusters form a sheet through oxide bridges. Half of the bridges are cation-cation interactions between the uranyl oxygen atom and molybdenum, the first reported of this kind., (© 2024 Wiley-VCH GmbH.)