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101.
Concurrent determination of olanzapine,risperidone and 9‐hydroxyrisperidone in human plasma by ultra performance liquid chromatography with diode array detection method: application to pharmacokinetic study 下载免费PDF全文
A simple and sensitive ultra‐performance liquid chromatography (UPLC) method has been developed and validated for simultaneous estimation of olanzapine (OLZ), risperidone (RIS) and 9‐hydroxyrisperidone (9‐OHRIS) in human plasma in vitro. The sample preparation was performed by simple liquid–liquid extraction technique. The analytes were chromatographed on a Waters Acquity H class UPLC system using isocratic mobile phase conditions at a flow rate of 0.3 mL/min and Acquity UPLC BEH shield RP18 column maintained at 40°C. Quantification was performed on a photodiode array detector set at 277 nm and clozapine was used as internal standard (IS). OLZ, RIS, 9‐OHRIS and IS retention times were found to be 0.9, 1.4, .1.8 and 3.1 min, respectively, and the total run time was 4 min. The method was validated for selectivity, specificity, recovery, linearity, accuracy, precision and sample stability. The calibration curve was linear over the concentration range 1–100 ng/mL for OLZ, RIS and 9‐OHRIS. Intra‐ and inter‐day precisions for OLZ, RIS and 9‐OHRIS were found to be good with the coefficient of variation <6.96%, and the accuracy ranging from 97.55 to 105.41%, in human plasma. The validated UPLC method was successfully applied to the pharmacokinetic study of RIS and 9‐OHRIS in human plasma. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
102.
A novel fast method for aqueous derivatization of THC,OH‐THC and THC‐COOH in human whole blood and urine samples for routine forensic analyses 下载免费PDF全文
《Biomedical chromatography : BMC》2018,32(4)
A novel aqueous in situ derivatization procedure with propyl chloroformate (PCF) for the simultaneous, quantitative analysis of Δ9‐tetrahydrocannabinol (THC), 11‐hydroxy‐Δ9‐tetrahydrocannabinol (OH‐THC) and 11‐nor‐Δ9‐tetrahydrocannabinol‐carboxylic acid (THC‐COOH) in human blood and urine is proposed. Unlike current methods based on the silylating agent [N,O‐bis(trimethylsilyl)trifluoroacetamide] added in an anhydrous environment, this new proposed method allows the addition of the derivatizing agent (propyl chloroformate, PCF) directly to the deproteinized blood and recovery of the derivatives by liquid–liquid extraction. This novel method can be also used for hydrolyzed urine samples. It is faster than the traditional method involving a derivatization with trimethyloxonium tetrafluoroborate. The analytes are separated, detected and quantified by gas chromatography–mass spectrometry in selected ion monitoring mode (SIM). The method was validated in terms of selectivity, capacity of identification, limits of detection (LOD) and quantification (LOQ), carryover, linearity, intra‐assay precision, inter‐assay precision and accuracy. The LOD and LOQ in hydrolyzed urine were 0.5 and 1.3 ng/mL for THC and 1.2 and 2.6 ng/mL for THC‐COOH, respectively. In blood, the LOD and LOQ were 0.2 and 0.5 ng/mL for THC, 0.2 and 0.6 ng/mL for OH‐THC, and 0.9 and 2.4 ng/mL for THC‐COOH, respectively. This method was applied to 35 urine samples and 50 blood samples resulting to be equivalent to the previously used ones with the advantage of a simpler method and faster sample processing time. We believe that this method will be a more convenient option for the routine analysis of cannabinoids in toxicological and forensic laboratories. 相似文献
103.
《Biomedical chromatography : BMC》2018,32(9)
Curcumin (CUR) is the major active component of turmeric and plays an important role in the prevention and treatment of many chronic diseases such as respiratory and neurodegenerative disease. In the present work, a rapid and simple LC–MS/MS method was developed to investigate the pharmacokinetics and tissue distribution of CUR and its metabolites in mice after intravenous administration of CUR (20 mg/kg). The results showed that the values of AUC0–∞ were 107.0 ± 18.3, 6.0 ± 1.2 and 12.0 ± 4.0 (mg/L) min, and those for t1/2z were 32.4 ± 10.8, 6.4 ± 2.4 and 5.6 ± 1.8 min for CUR, dihydrocurcumin (DHC) and tetrahydrocurcumin (THC) in plasma, respectively. CUR and THC could be detected in liver while CUR and DHC were detected in kidney. Only CUR was detected in brain. These findings indicated that THC was the main metabolite of CUR in plasma. The exposure of CUR in plasma was 6‐fold greater than that in liver, kidney and brain. 相似文献
104.
Synthesis,characterization and biological screening studies of mixed ligand complexes using flavonoids as precursors 下载免费PDF全文
Flavonoids are a group of plant phenolics that provide various health benefits through cell signalling pathways and antioxidant effects. In the present study, a new series of mixed ligand complexes of Co(II), Ni(II), Cu(II) and Zn(II) were synthesized by incorporating curcumin and quercetin flavonoid precursors. The structural features of the synthesized complexes were explored using elemental analysis, thermogravimetric analysis, UV–visible, infrared, NMR, mass and electron paramagnetic resonance spectral analyses and conductivity measurements. These data support an octahedral geometry of the synthesized complexes. In silico biological activity score for the ligand was predicted using PASS online software. ADMET properties were studied using VLS3D online software. Anti‐inflammatory and antioxidant activities were experimentally validated which prove that theoretical predictions are in agreement with the experimental results. Interestingly the synthesized complexes interact with calf thymus DNA through groove binding mode. Moreover, they have good potential to cleave pUC19 DNA. Minimum inhibitory concentration values of the synthesized complexes reveal that they have better antimicrobial efficacy than the ligands. 相似文献
105.
《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2017,129(45):14375-14379
Herein we report the colloidal synthesis of Cs3Sb2I9 and Rb3Sb2I9 perovskite nanocrystals, and explore their potential for optoelectronic applications. Different morphologies, such as nanoplatelets and nanorods of Cs3Sb2I9, and spherical Rb3Sb2I9 nanocrystals were prepared. All these samples show band‐edge emissions in the yellow–red region. Exciton many‐body interactions studied by femtosecond transient absorption spectroscopy of Cs3Sb2I9 nanorods reveals characteristic second‐derivative‐type spectral features, suggesting red‐shifted excitons by as much as 79 meV. A high absorption cross‐section of ca. 10−15 cm2 was estimated. The results suggest that colloidal Cs3Sb2I9 and Rb3Sb2I9 nanocrystals are potential candidates for optical and optoelectronic applications in the visible region, though a better control of defect chemistry is required for efficient applications. 相似文献
106.
This work is an extension of our earlier article, where a well-known integral representation of the logarithmic function was explored and was accompanied with demonstrations of its usefulness in obtaining compact, easily-calculable, exact formulas for quantities that involve expectations of the logarithm of a positive random variable. Here, in the same spirit, we derive an exact integral representation (in one or two dimensions) of the moment of a nonnegative random variable, or the sum of such independent random variables, where the moment order is a general positive non-integer real (also known as fractional moments). The proposed formula is applied to a variety of examples with an information-theoretic motivation, and it is shown how it facilitates their numerical evaluations. In particular, when applied to the calculation of a moment of the sum of a large number, n, of nonnegative random variables, it is clear that integration over one or two dimensions, as suggested by our proposed integral representation, is significantly easier than the alternative of integrating over n dimensions, as needed in the direct calculation of the desired moment. 相似文献
107.
《应用有机金属化学》2017,31(4)
Metal–organic framework of NH2‐MIL‐53(Al), with coordinative unsaturated aluminium sites, has been shown to be active in the Groebke–Blackburn–Bienaymé multicomponent coupling reaction based on Ugi‐type amine and aldehyde condensation over isocyanide and then a cyclization process. Interestingly this reaction occurred under solvent‐free conditions with high yield, in which the NH2‐MIL‐53(Al) could be recovered and reused for five reaction cycles, giving a total turnover number of 455. 相似文献
108.
Three phase transitions between 100 and 400 K were previously shown by X-ray diffraction measurements. Such results have been confirmed by optical measurements on crystals. The thermal dependence of the birefringence has been determined. A new phase transformation has been shown at around 590 K not only by optical study but also by dielectric measurements. Ferroelastic domain-walls have been visualized. The sequence transition has been discussed taking into account the various space groups. 相似文献
109.
The ionization process of B2+ by H+ impact is studied using the continuum-distorted-wave eikonal-initial-state (CDW-EIS) method and the modified free electron peak approximation (M-FEPA), respectively. Total, single-, and double- differential cross sections from 1s and 2s orbitals are presented for the energy range from 10 keV/u to 10 MeV/u. Comparison between the results from the two methods demonstrates that the total and single-differential cross sections for the high-energy incident projectile case can be well evaluated using the simple M-FEPA model. Moreover, the M-FEPA model reproduces the essential features of the binary-encounter (BE) bump in the double-differential cross sections. Thus, the BE ionization mechanism is discussed in detail by adopting the M-FEPA model. In particular, the double- and single-differential cross sections from the 2s orbital show a high-energy hip, which is different from those from the 1s orbital. Based on Ref. [1], the Compton profiles of B2+ for 1s and 2s orbitals are given, and the hips in DDCS and SDCS from the 2s orbital are explained. 相似文献
110.
Jun‐Sheng Duan Randolph Rach Shi‐Ming Lin 《Mathematical Methods in the Applied Sciences》2013,36(13):1790-1804
We present a new approach to calculate analytic approximations of blow‐up solutions and their critical blow‐up times. Our approach applies the Adomian decomposition–Padé method to quickly and easily compute the critical blow‐up times, which comprises the Adomian decomposition method combined with the Padé approximants technique. We validate our new approach with a variety of numerical examples, including nonlinear ODEs, systems of nonlinear ODEs, and nonlinear PDEs. Furthermore, our new method is shown to be more convenient than prior art that relies on compound discretized algorithms. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献