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Chaolong Qin Wanshan Feng YenJu Chu Jong Bong Lee Mattia Berton Sara Bettonte Yeong Yeu Teo Michael J. Stocks Peter M. Fischer Pavel Gershkovich 《Biomedical chromatography : BMC》2020,34(11):e4934
A simple, sensitive and cost-effective HPLC-UV bioanalytical method for determination of lopinavir (LPV) in rat and human plasma was developed and validated. The plasma sample preparation procedure includes a combination of protein precipitation using cold acetonitrile and liquid–liquid extraction with n-hexane–ethyl acetate (7:3, v/v). A good chromatographic separation was achieved with a Phenomenex Gemini column (C18, 150 mm × 2.0 mm, 5 μm) at 40°C with gradient elution, at 211 nm. Calibration curves were linear in the range 10–10,000 ng/mL, with a lower limit of quantification of 10 ng/mL using 100 μL of plasma. The accuracy and precision in all validation experiments were within the criteria range set by the guidelines of the Food and Drug Administration. This method was successfully applied to a preliminary pharmacokinetic study in rats following an intravenous bolus administration of LPV. Moreover, the method was subsequently fully validated for human plasma, allowing its use in therapeutic drug monitoring (TDM). In conclusion, this novel, simple and cost-efficient bioanalytical method for determination of LPV is useful for pharmacokinetic and drug delivery studies in rats, as well as TDM in human patients. 相似文献
123.
Dr. Carla Bazzicalupi Dr. Claudia Caltagirone Dr. Zenfeng Cao Dr. Qibin Chen Prof. Corrado Di Natale Dr. Alessandra Garau Prof. Dr. Vito Lippolis Dr. Larisa Lvova Dr. Honglai Liu Prof. Dr. Ingemar Lundström Dr. M. Cristina Mostallino Mattia Nieddu Prof. Roberto Paolesse Prof. Dr. Luca Prodi Massimo Sgarzi Dr. Nelsi Zaccheroni 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(43):14639-14653
Despite several types of fluorescent sensing molecules have been proposed and examined to signal Hg2+ ion binding, the development of fluorescence‐based devices for in‐field Hg2+ detection and screening in environmental and industrial samples is still a challenging task. Herein, we report the synthesis and characterization of three new coumarin‐based fluorescent chemosensors featuring mixed thia/aza macrocyclic framework as receptors units, that is, ligands L1 – L3 . These probes revealed an OFF–ON selective response to the presence of Hg2+ ions in MeCN/H2O 4:1 (v/v), which allowed imaging of this metal ion in Cos‐7 cells in vitro. Once included in silica core–polyethylene glycol (PEG) shell nanoparticles or supported on polyvinyl chloride (PVC)‐based polymeric membranes, ligands L1 – L3 can also selectively sense Hg2+ ions in pure water. In particular we have developed an optical sensing array tacking advantage of the fluorescent properties of ligand L3 and based on the computer screen photo assisted technique (CSPT). In the device ligand L3 is dispersed into PVC membranes and it quantitatively responds to Hg2+ ions in natural water samples. 相似文献
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Raffaella Puliti Carlo A. Mattia Alessia De Fazio Maria R. Ghiara Lelio Mazzarella 《Acta Crystallographica. Section C, Structural Chemistry》2001,57(12):1447-1449
The title compound, (3R,4S,8R,9S)-cinchoninium (2R,3R)-tartrate tetrahydrate, C19H23N2O+·C4H5O6−·4H2O, is a hydrated salt of cinchonine. In the cinchoninium cation, the geometry around the quinuclidinic N atom is typical of a protonated N atom, and the bond lengths and angles in the tartrate moiety clearly indicate the mono-ionized form. The relative orientation of the quinoline and quinuclidine systems is that most frequently observed in structures of cinchona salts and corresponds to one of the energy minima calculated for this type of molecule in the gas phase. An extended network of intermolecular hydrogen bonds spreads parallel to the bc plane separating apolar layers. 相似文献
125.
We investigate the morphology of a pentacene (C22H14) film adsorbed on the Cu(1 1 9) vicinal surface by scanning tunnelling microscopy (STM). Thermal treatment of a thick film of molecules generates a long-range ordered structure. Series of molecular rows are alternated with areas where the molecules assume two equivalent orientations. STM data analysis suggests that the ordered structure can be described by a rippled morphology. The behaviour of the film at different annealing temperatures suggests a possible explanation of the film structure as due to an adsorbate-induced modification of the substrate. 相似文献
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Mattia Gazzola Philippe Chatelain Wim M. van Rees Petros Koumoutsakos 《Journal of computational physics》2011,230(19):7093-7114
We present a vortex particle method coupled with a penalization technique to simulate single and multiple swimmers in an incompressible, viscous flow in two and three dimensions. The proposed algorithm can handle arbitrarily deforming bodies and their corresponding non-divergence free deformation velocity fields. The method is validated on a number of benchmark problems with stationary and moving boundaries. Results include flows of tumbling objects and single and multiple self-propelled swimmers. 相似文献
130.
C.?ManninoEmail author S.?Mattia A.?Sassano 《Computational Optimization and Applications》2011,48(3):533-551
Transmitters and receivers are the basic elements of wireless networks and are characterized by a number of radio-electrical
parameters. The generic planning problem consists of establishing suitable values for these parameters so as to optimize some
network performance indicator. The version here addressed, namely the Power Assignment Problem (pap), is the problem of assigning transmission powers to the transmitters of a wireless network so as to maximize the satisfied
demand. This problem has relevant practical applications both in radio-broadcasting and in mobile telephony. Typical solution
approaches make use of mixed integer linear programs with huge coefficients in the constraint matrix yielding numerical inaccuracy
and poor bounds, and so cannot be exploited to solve large instances of practical interest. In order to overcome these inconveniences,
we developed a two-phase heuristic to solve large instances of pap, namely a constructive heuristic followed by an improving local search. Both phases are based on successive shortest path
computations on suitable directed graphs. Computational tests on a number of instances arising in the design of the national
Italian Digital Video Broadcasting (DVB) network are presented. 相似文献