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101.
Gemechu Zeleke Siegrid De Baere Sultan Suleman Mathias Devreese 《Molecules (Basel, Switzerland)》2022,27(3)
A fast, accurate and reliable ultra-high performance liquid chromatography–tandem mass spectrometry (UHPLC-MS/MS) method was developed for simultaneous quantification of ivermectin (IVER), doramectin (DORA), and moxidectin (MOXI) in bovine plasma. A priority for sample preparation was the eradication of possible infectious diseases to avoid travel restrictions. The sample preparation was based on protein precipitation using 1% formic acid in acetonitrile, followed by Ostro® 96-well plate pass-through sample clean-up. The simple and straightforward procedure, along with the short analysis time, makes the current method unique and suitable for a large set of sample analyses per day for PK studies. Chromatographic separation was performed using an Acquity UPLC HSS-T3 column, with 0.01% acetic acid in water and methanol, on an Acquity H-Class ultra-high performance liquid chromatograph (UHPLC) system. The MS/MS instrument was a Xevo TQ-S® mass spectrometer, operating in the positive electrospray ionization mode and two multiple reaction monitoring (MRM) transitions were monitored per component. The MRM transitions of m/z 897.50 > 753.4 for IVER, m/z 921.70 > 777.40 for DORA and m/z 640.40 > 123.10 for MOXI were used for quantification. The method validation was performed using matrix-matched calibration curves in a concentration range of 1 to 500 ng/mL. Calibration curves fitted a quadratic regression model with 1/x2 weighting (r ≥ 0.998 and GoF ≤ 4.85%). Limits of quantification (LOQ) values of 1 ng/mL were obtained for all the analytes, while the limits of detection (LOD) were 0.02 ng/mL for IVER, 0.03 ng/mL for DORA, and 0.58 ng/mL for MOXI. The results of within-day (RSD < 6.50%) and between-day (RSD < 8.10%) precision and accuracies fell within acceptance ranges. No carry-over and no peak were detected in the UHPLC-MS/MS chromatogram of blank samples showing good specificity of the method. The applicability of the developed method was proved by an analysis of the field PK samples. 相似文献
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We investigate minimum vertex degree conditions for 3-uniform hypergraphs which ensure the existence of loose Hamilton cycles. A loose Hamilton cycle is a spanning cycle in which only consecutive edges intersect and these intersections consist of precisely one vertex. 相似文献
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Madalan AM Roesky HW Andruh M Noltemeyer M Stanica N 《Chemical communications (Cambridge, England)》2002,(15):1638-1639
A novel heterospin system, [(CuL)2Gd(TCNQ)2].TCNQ-.CH3OH.2CH3CN, is obtained by reacting the mononuclear complex, [CuL], with gadolinium(III) nitrate, followed by the substitution of the nitrato ions with anionic organic radicals. 相似文献
109.
We demonstrate generalized ellipsometry for precise measurement of the principal indices of refraction, the extinction coefficients, and the orientations of the crystal a, b, and c axes of orthorhombic absorbing materials. Stibnite (Sb(2)S(3)) single crystals cut approximately parallel to (100), (010), (001), and (313) are studied at a representative wavelength of 589 nm. The (313) surface is sufficient for retrieval of all optical constants. The expected effects of surface over-layer formation are removed numerically. We propose generalized ellipsometry as a powerful tool for measurement of anisotropic optical function spectra of biaxial materials. 相似文献
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