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Pralidoxime chloride, a highly hydrophilic antidote, cannot be effectively separated by reverse-phase high-performance liquid chromatography (RP-HPLC), unless the mobile-phase composition is varied. However, the use of ion-pairing reagents for pralidoxime separation is hindered by the persistent contamination of the stationary phase or chromatography system inside the HPLC system. Thus, this study aimed to develop a simple, rapid, and robust method based on RP-HPLC to determine pralidoxime chloride in antidote autoinjectors using a chaotropic salt as the mobile-phase additive. The use of UV detection at 270 nm allowed for the simultaneous detection of pralidoxime chloride and the internal standard, pyridine-2-aldoxime. The addition of chaotropic salts (NaPF6, NaBF4, and NaClO4) and an ionic liquid ([EMIM]PF6) increased the retention time of pralidoxime chloride. Among them, NaPF6 exhibited the highest capacity factor in the reverse-phase C18 column. Increasing the salt concentration increased the capacity factor and the number of theoretical plates. Analytical method validation was performed to assess the linearity, accuracy, precision, recovery, and repeatability, according to the Ministry of Food and Drug Safety guidelines. Additionally, this newly developed method exhibits an adequate separation capability, making it a potential substitute for the current method employed in the United States/Korean Pharmacopoeia, and it ensures the necessary durability to maintain the robustness and reliability of the analytical system. [ABSTRACT FROM AUTHOR]

Direct CH amidation of arylphosphoryl compounds has been developed by using an IrIII catalyst system under mild conditions. A wide range of substrates could be employed with high functional-group tolerance. This procedure was successfully applied for the first time to the asymmetric reaction giving rise to a P-chirogenic center with a high diastereomeric ratio of up to 19:1 (90 % de). [ABSTRACT FROM AUTHOR]

Herein, a B 5 -site-rich Ru/MgAl 2 O 4 nanocatalyst for the production of CO x -free hydrogen from ammonia (NH 3 ) is synthesized using the polyol method. The polyol method enables size-sensitive Ru-nanoparticle growth and controlled B 5 -site formation on the catalyst by tuning the carbon-chain length of the polyol solvent used, obviating the use of a separate stabilizer and enhancing electron donation from Ru (with a high surface electron density) and π-back bonding. The Ru/MgAl 2 O 4 (BG) catalyst synthesized using butylene glycol (a long-carbon-chain solvent) contains 2.5 nm Ru particles uniformly dispersed on its surface and abundant B 5 sites at (0 0 2)/(0 1 1). Moreover, the Ru/MgAl 2 O 4 (BG) catalyst exhibits lower activation energy (48.9 kJ mol -1 ) and higher H 2 formation rate (565-1,236 mmol g cat -1 h -1 at 350-450 °C and a weight hourly space velocity of 30,000 mL g cat -1 h -1 ) during the NH 3 decomposition reaction than catalysts with a similar Ru particle size and high metal dispersion synthesized by the impregnation and deposition-precipitation methods. This high performance is possibly because the abundant electron-donating B 5 sites on the catalyst surface accelerate the recombination-desorption of N 2 , which is the rate-determining step of the NH 3 decomposition reaction at low temperatures. Thus, this study facilitates clean hydrogen production., (© 2024 The Author(s). Small published by Wiley‐VCH GmbH.)

Spatial pattern detection can be a useful tool for understanding the geographical distribution of cancer mortality. This study compared the results from several special analysis methods to examine the geographical variations in Korean major cancer mortality during 2010 to 2013. The spatial scan statistic and Tango's method were used to detect spatial clusters with unusually high or low rates. The local indicator of spatial association was used for cluster detection with accounting for spatial autocorrelation among adjacent areas. A nonparametric approach was used to identify local districts with significantly higher or lower rates, compared to the average national rate. The different methods revealed similar results in the overall patterns, but slightly different specific results. These techniques can provide complementary information and should be used based on the distinguishing features of each method. It may be better to use several different methods for these analyses rather than a single method., (© 2016 APJPH.)