A novel method for quantifying the concentration of lactulose, rhamnose, xylose, and 3-O-methylglucose (3-OMG) in cat plasma using liquid chromatography-mass spectrometry (LC-MS) was developed. Domestic male cats (n = 13) were orally dosed with a solution containing the four sugars to test the permeability and absorptive capacity of their intestinal barrier. Plasma samples were taken 3 h later and were prepared with acetonitrile (ACN), dried under N2, and reconstituted in 90 % ACN with 1 mM ammonium formate. Stable isotope labelled 13C standards for each analyte were used as internal standards. Chromatographic separation was conducted using a Phenomenex Luna NH2 column with a gradient elution system of deionized water and 90 % ACN with 1 mM ammonium formate at 300 µL/min for 13 min total analysis time. Recovery trials were conducted in triplicate over three days with RSD values (%) for each day ranging from 1.2 to 1.4 for lactulose, 5.4 - 6.0 for rhamnose, 3.3 - 5.5 for xylose, and 2.6 - 5.6 for 3-OMG. Inter-day variations for each analyte were not different (p > 0.05). Limit of detection and quantification were 0.2 and 0.7 µg/mL for lactulose, 0.8 and 2.4 µg/mL for rhamnose, 0.6 and 1.8 µg/mL for xylose, and 0.3 and 1.1 µg/mL for 3-OMG, respectively. Plasma sugar concentrations recovered from cats were above the limit of quantification and below the highest calibration standard, validating the use of this method to test intestinal permeability and absorptive capacity in cats.

Water samples from Waiora Drinking Water Treatment Plant in New Zealand were analyzed using excitation-emission matrix fluorescence spectroscopy (EEMS) and parallel factor (PARAFAC) analysis to evaluate organic matter removal across the plant. The assessment also included the individual granular activated carbon (GAC) filters since the filters had varying media ages due to partial media replacement over a 10-month period, presenting a unique assessment opportunity. PARAFAC analysis identified humic-like, tyrosine-protein-like, and tryptophan-protein-like components representing fluorescent dissolved organic matter groups. The humic-like component strongly correlated with total organic carbon (TOC) concentration and removal was significantly influenced by filter media age. However, protein-like components had minimal TOC correlation and were not effectively removed by the overall plant treatment irrespective of filter media age. These findings have implications for disinfection, taste and odor, and bacterial regrowth and require an improved media replacement strategy. Further study of the protein-like components is required.

A comparison of granular and biological activated carbon (GAC and BAC) media used for drinking water treatment was made to assess differences in surface elemental composition. Fresh GAC, recently commissioned GAC and end-of-service life BAC from a water treatment plant in New Zealand were analyzed using scanning electron microscopy, energy-dispersive spectroscopy, and inductively coupled plasma-mass spectrometry (ICP-MS). Imaging revealed dense microbial colonization of the BAC surface compared to GAC media, and a mineralized surface layer high in manganese and oxygen. ICP-MS analysis also confirmed high levels of Mn in the BAC media relative to GAC media. As many bacterial species known to colonize BAC filters are also known as Mn oxidizers, this suggests a biogenic origin of the Mn-oxide deposition on the BAC surface. Given the properties of Mn-oxides, they may be implicated in the mechanism by which bacteria capture and metabolize substrates in BAC filters.

The crystal structures of analogous 1-(4-halo-2,3,5,6-tetrafluorophenyl)-3-benzylimidazolium bromide salts have been determined by single crystal X-ray diffraction. All three structures contain similar charge-assisted hydrogen bonding between the acidic hydrogen atoms of the imidazolium ring and bromide anions, but different structures arise because of the relative importance of other interactions, in particular the halogen bonding between bromide and the covalently bonded halogen atoms. 1-(4-Chloro-2,3,5,6-tetrafluorophenyl)-3-benzylimidazolium bromide (1) comprises columns of pi-pi stacked phenyl and chlorotetrafluorophenyl rings in three almost orthogonal directions, 1-(4-bromo-2,3,5,6-tetrafluorophenyl)-3-benzylimidazolium bromide (2) contains columns of alternating bromotetrafluorophenyl rings and bromide anions displaying anion-pi interactions, and 1-(4-iodo-2,3,5,6-tetrafluorophenyl)-3-benzylimidazolium bromide (3) contains columns of alternating iodotetrafluorophenyl rings and iodine atoms displaying lone pair-pi interactions.

The crystal structure of 1-(4-bromo-2,3,5,6-tetrafluorophenyl)-3-benzylimidazolium bromide comprises columns of parallel bromotetrafluorophenyl rings with an interplanar distance of 6.936(6) angstrom separated by bromide anions.