The Experts below are selected from a list of 192 Experts worldwide ranked by ideXlab platform

Lanhua Chen - One of the best experts on this subject based on the ideXlab platform.

  • direct chemiluminescence determination of Fenbufen by the enhancement of the text ru left text phen right _3 2 cerium iv system
    Mikrochimica Acta, 2008
    Co-Authors: Fengshan Yu, Fang Chen, Lanhua Chen
    Abstract:

    A method is described for determination of Fenbufen that is based on the chemiluminescence (CL) reaction of the \({\text{Ru}}\left( {{\text{phen}}} \right)_3^{2 + } \)–cerium(IV)–Fenbufen system. An enhanced CL reaction was developed, and optimum conditions for CL were investigated. The CL was linearly dependent on Fenbufen concentration in the range 4.0 × 10−8–9.0 × 10−6 mol L−1. The detection limit was 2.0 × 10−8 mol L−1. The relative standard deviation (RSD) was 2.8% for eleven measurements of 6.0 × 10−7 mol L−1 Fenbufen standard solution. The new method enables simple, sensitive, and rapid determination of Fenbufen and has been used for determination of Fenbufen in pharmaceutical preparations in capsule, spiked serum and urine samples.

  • Direct chemiluminescence determination of Fenbufen by the enhancement of the $${\text{Ru}}\left( {{\text{phen}}} \right)_3^{2 + } $$ –cerium(IV) system
    Mikrochimica Acta, 2008
    Co-Authors: Fengshan Yu, Fang Chen, Lanhua Chen
    Abstract:

    A method is described for determination of Fenbufen that is based on the chemiluminescence (CL) reaction of the \({\text{Ru}}\left( {{\text{phen}}} \right)_3^{2 + } \)–cerium(IV)–Fenbufen system. An enhanced CL reaction was developed, and optimum conditions for CL were investigated. The CL was linearly dependent on Fenbufen concentration in the range 4.0 × 10−8–9.0 × 10−6 mol L−1. The detection limit was 2.0 × 10−8 mol L−1. The relative standard deviation (RSD) was 2.8% for eleven measurements of 6.0 × 10−7 mol L−1 Fenbufen standard solution. The new method enables simple, sensitive, and rapid determination of Fenbufen and has been used for determination of Fenbufen in pharmaceutical preparations in capsule, spiked serum and urine samples.

  • direct chemiluminescence determination of Fenbufen by the enhancement of the ru phen 2 3 cerium iv system
    Mikrochimica Acta, 2008
    Co-Authors: Fengshan Yu, Fang Chen, Lanhua Chen
    Abstract:

    A method is described for determination of Fenbufen that is based on the chemiluminescence (CL) reaction of the Ru(phen) 2+ 3 +-cerium(IV)-Fenbufen system. An enhanced CL reaction was developed, and optimum conditions for CL were investigated. The CL was linearly dependent on Fenbufen concentration in the range 4.0× 10 -8 -9.0×10 -6 mol L -1 . The detection limit was 2.0× 10 -8 mol L -1 . The relative standard deviation (RSD) was 2.8% for eleven measurements of 6.0×10 -7 mol L -1 Fenbufen standard solution. The new method enables simple, sensitive, and rapid determination of Fenbufen and has been used for determination of Fenbufen in pharmaceutical preparations in capsule, spiked serum and urine samples.

  • direct chemiluminescence determination of Fenbufen by the enhancement of the formula cerium iv system
    Mikrochimica Acta, 2008
    Co-Authors: Fengshan Yu, Fang Chen, Lanhua Chen
    Abstract:

    A method is described for determination of Fenbufen that is based on the chemiluminescence (CL) reaction of the [FORMULA]-cerium(IV)-Fenbufen system. An enhanced CL reaction was developed, and optimum conditions for CL were investigated. The CL was linearly dependent on Fenbufen concentration in the range 4.0 × 10 −8 -9.0 × 10 −6 mol L −1 . The detection limit was 2.0 × 10 −8 mol L −1 . The relative standard deviation (RSD) was 2.8% for eleven measurements of 6.0 × 10 −7 mol L −1 Fenbufen standard solution. The new method enables simple, sensitive, and rapid determination of Fenbufen and has been used for determination of Fenbufen in pharmaceutical preparations in capsule, spiked serum and urine samples.

Fengshan Yu - One of the best experts on this subject based on the ideXlab platform.

  • direct chemiluminescence determination of Fenbufen by the enhancement of the text ru left text phen right _3 2 cerium iv system
    Mikrochimica Acta, 2008
    Co-Authors: Fengshan Yu, Fang Chen, Lanhua Chen
    Abstract:

    A method is described for determination of Fenbufen that is based on the chemiluminescence (CL) reaction of the \({\text{Ru}}\left( {{\text{phen}}} \right)_3^{2 + } \)–cerium(IV)–Fenbufen system. An enhanced CL reaction was developed, and optimum conditions for CL were investigated. The CL was linearly dependent on Fenbufen concentration in the range 4.0 × 10−8–9.0 × 10−6 mol L−1. The detection limit was 2.0 × 10−8 mol L−1. The relative standard deviation (RSD) was 2.8% for eleven measurements of 6.0 × 10−7 mol L−1 Fenbufen standard solution. The new method enables simple, sensitive, and rapid determination of Fenbufen and has been used for determination of Fenbufen in pharmaceutical preparations in capsule, spiked serum and urine samples.

  • Direct chemiluminescence determination of Fenbufen by the enhancement of the $${\text{Ru}}\left( {{\text{phen}}} \right)_3^{2 + } $$ –cerium(IV) system
    Mikrochimica Acta, 2008
    Co-Authors: Fengshan Yu, Fang Chen, Lanhua Chen
    Abstract:

    A method is described for determination of Fenbufen that is based on the chemiluminescence (CL) reaction of the \({\text{Ru}}\left( {{\text{phen}}} \right)_3^{2 + } \)–cerium(IV)–Fenbufen system. An enhanced CL reaction was developed, and optimum conditions for CL were investigated. The CL was linearly dependent on Fenbufen concentration in the range 4.0 × 10−8–9.0 × 10−6 mol L−1. The detection limit was 2.0 × 10−8 mol L−1. The relative standard deviation (RSD) was 2.8% for eleven measurements of 6.0 × 10−7 mol L−1 Fenbufen standard solution. The new method enables simple, sensitive, and rapid determination of Fenbufen and has been used for determination of Fenbufen in pharmaceutical preparations in capsule, spiked serum and urine samples.

  • direct chemiluminescence determination of Fenbufen by the enhancement of the ru phen 2 3 cerium iv system
    Mikrochimica Acta, 2008
    Co-Authors: Fengshan Yu, Fang Chen, Lanhua Chen
    Abstract:

    A method is described for determination of Fenbufen that is based on the chemiluminescence (CL) reaction of the Ru(phen) 2+ 3 +-cerium(IV)-Fenbufen system. An enhanced CL reaction was developed, and optimum conditions for CL were investigated. The CL was linearly dependent on Fenbufen concentration in the range 4.0× 10 -8 -9.0×10 -6 mol L -1 . The detection limit was 2.0× 10 -8 mol L -1 . The relative standard deviation (RSD) was 2.8% for eleven measurements of 6.0×10 -7 mol L -1 Fenbufen standard solution. The new method enables simple, sensitive, and rapid determination of Fenbufen and has been used for determination of Fenbufen in pharmaceutical preparations in capsule, spiked serum and urine samples.

  • direct chemiluminescence determination of Fenbufen by the enhancement of the formula cerium iv system
    Mikrochimica Acta, 2008
    Co-Authors: Fengshan Yu, Fang Chen, Lanhua Chen
    Abstract:

    A method is described for determination of Fenbufen that is based on the chemiluminescence (CL) reaction of the [FORMULA]-cerium(IV)-Fenbufen system. An enhanced CL reaction was developed, and optimum conditions for CL were investigated. The CL was linearly dependent on Fenbufen concentration in the range 4.0 × 10 −8 -9.0 × 10 −6 mol L −1 . The detection limit was 2.0 × 10 −8 mol L −1 . The relative standard deviation (RSD) was 2.8% for eleven measurements of 6.0 × 10 −7 mol L −1 Fenbufen standard solution. The new method enables simple, sensitive, and rapid determination of Fenbufen and has been used for determination of Fenbufen in pharmaceutical preparations in capsule, spiked serum and urine samples.

Fang Chen - One of the best experts on this subject based on the ideXlab platform.

  • direct chemiluminescence determination of Fenbufen by the enhancement of the text ru left text phen right _3 2 cerium iv system
    Mikrochimica Acta, 2008
    Co-Authors: Fengshan Yu, Fang Chen, Lanhua Chen
    Abstract:

    A method is described for determination of Fenbufen that is based on the chemiluminescence (CL) reaction of the \({\text{Ru}}\left( {{\text{phen}}} \right)_3^{2 + } \)–cerium(IV)–Fenbufen system. An enhanced CL reaction was developed, and optimum conditions for CL were investigated. The CL was linearly dependent on Fenbufen concentration in the range 4.0 × 10−8–9.0 × 10−6 mol L−1. The detection limit was 2.0 × 10−8 mol L−1. The relative standard deviation (RSD) was 2.8% for eleven measurements of 6.0 × 10−7 mol L−1 Fenbufen standard solution. The new method enables simple, sensitive, and rapid determination of Fenbufen and has been used for determination of Fenbufen in pharmaceutical preparations in capsule, spiked serum and urine samples.

  • Direct chemiluminescence determination of Fenbufen by the enhancement of the $${\text{Ru}}\left( {{\text{phen}}} \right)_3^{2 + } $$ –cerium(IV) system
    Mikrochimica Acta, 2008
    Co-Authors: Fengshan Yu, Fang Chen, Lanhua Chen
    Abstract:

    A method is described for determination of Fenbufen that is based on the chemiluminescence (CL) reaction of the \({\text{Ru}}\left( {{\text{phen}}} \right)_3^{2 + } \)–cerium(IV)–Fenbufen system. An enhanced CL reaction was developed, and optimum conditions for CL were investigated. The CL was linearly dependent on Fenbufen concentration in the range 4.0 × 10−8–9.0 × 10−6 mol L−1. The detection limit was 2.0 × 10−8 mol L−1. The relative standard deviation (RSD) was 2.8% for eleven measurements of 6.0 × 10−7 mol L−1 Fenbufen standard solution. The new method enables simple, sensitive, and rapid determination of Fenbufen and has been used for determination of Fenbufen in pharmaceutical preparations in capsule, spiked serum and urine samples.

  • direct chemiluminescence determination of Fenbufen by the enhancement of the ru phen 2 3 cerium iv system
    Mikrochimica Acta, 2008
    Co-Authors: Fengshan Yu, Fang Chen, Lanhua Chen
    Abstract:

    A method is described for determination of Fenbufen that is based on the chemiluminescence (CL) reaction of the Ru(phen) 2+ 3 +-cerium(IV)-Fenbufen system. An enhanced CL reaction was developed, and optimum conditions for CL were investigated. The CL was linearly dependent on Fenbufen concentration in the range 4.0× 10 -8 -9.0×10 -6 mol L -1 . The detection limit was 2.0× 10 -8 mol L -1 . The relative standard deviation (RSD) was 2.8% for eleven measurements of 6.0×10 -7 mol L -1 Fenbufen standard solution. The new method enables simple, sensitive, and rapid determination of Fenbufen and has been used for determination of Fenbufen in pharmaceutical preparations in capsule, spiked serum and urine samples.

  • direct chemiluminescence determination of Fenbufen by the enhancement of the formula cerium iv system
    Mikrochimica Acta, 2008
    Co-Authors: Fengshan Yu, Fang Chen, Lanhua Chen
    Abstract:

    A method is described for determination of Fenbufen that is based on the chemiluminescence (CL) reaction of the [FORMULA]-cerium(IV)-Fenbufen system. An enhanced CL reaction was developed, and optimum conditions for CL were investigated. The CL was linearly dependent on Fenbufen concentration in the range 4.0 × 10 −8 -9.0 × 10 −6 mol L −1 . The detection limit was 2.0 × 10 −8 mol L −1 . The relative standard deviation (RSD) was 2.8% for eleven measurements of 6.0 × 10 −7 mol L −1 Fenbufen standard solution. The new method enables simple, sensitive, and rapid determination of Fenbufen and has been used for determination of Fenbufen in pharmaceutical preparations in capsule, spiked serum and urine samples.

Kikuo Iwamoto - One of the best experts on this subject based on the ideXlab platform.

  • effect of Fenbufen on the entry of new quinolones norfloxacin and ofloxacin into the central nervous system in rats
    Journal of Pharmacy and Pharmacology, 1992
    Co-Authors: Nobuhiro Ichikawa, Yoshihiro Katagiri, Kohji Naora, Masakazu Hayashibara, Kikuo Iwamoto
    Abstract:

    — The entry of two new quinolone antibacterial agents, norfloxacin and ofloxacin, into the central nervous system (CNS) of rats, and the effect of Fenbufen on this was investigated. At various times after the administration of a bolus intravenous dose of norfloxacin or ofloxacin (10 mg kg−1) with or without Fenbufen (20 mg kg−1), serum and cerebrospinal fluid (CSF) samples and whole brain were collected from the rats and the concentration of norfloxacin or ofloxacin in each sample was determined. Serum concentrations of both quinolones declined biexponentially with time and were significantly elevated by coadministration with Fenbufen at the terminal phase. The fractions of these quinolones bound to serum protein were not altered by coadministration with Fenbufen. Coadministered Fenbufen raised the brain concentrations of both quinolones but did not affect their brain to serum unbound concentration ratios. In contrast, CSF to serum unbound concentration ratios as well as CSF concentrations of norfloxacin and ofloxacin were elevated by coadministration with Fenbufen. Apparent diffusional clearances between blood and CSF of norfloxacin and ofloxacin estimated by the physiological model analysis increased by 1·9 and 2·6 times, respectively, after coadministration with Fenbufen. These findings suggest that coadministered Fenbufen may facilitate the entry of norfloxacin and ofloxacin into the CNS.

  • enhanced entry of ciprofloxacin into the rat central nervous system induced by Fenbufen
    Journal of Pharmacology and Experimental Therapeutics, 1991
    Co-Authors: Kohji Naora, Yoshihiro Katagiri, Masakazu Hayashibara, N Ichikawa, Kikuo Iwamoto
    Abstract:

    The effects of Fenbufen on the transport of ciprofloxacin (CPFX) into the brain and cerebrospinal fluid (CSF) were investigated in rats. Periodically after a bolus i.v. dose of CPFX (10 mg/kg), alone or with Fenbufen (20 mg/kg), to rats, aliquots of CSF and blood were collected and then the whole brain was readily excised from the animal after sacrifice by microwave irradiation. Serum levels of CPFX in the terminal phase were significantly elevated by the coadministration with Fenbufen. However, the extent of CPFX binding to serum protein was not affected by Fenbufen. Immediately after the coadministration with Fenbufen, brain and CSF levels of CPFX were raised by about 15 to 70% and 70 to 100%, respectively. Both brain/serum unbound and CSF/serum unbound level ratios were increased by Fenbufen at relatively early periods after drug injection. Analysis based on physiological models indicated that Fenbufen significantly increased the apparent diffusion clearances of CPFX across blood-brain and blood-CSF barriers. These findings suggest that coadministered Fenbufen may facilitate the entry of CPFX into the central nervous system not only by elevation of serum level but also by enhancement of permeability across the blood-brain or blood-CSF barrier.

  • a possible reduction in the renal clearance of ciprofloxacin by Fenbufen in rats
    Journal of Pharmacy and Pharmacology, 1990
    Co-Authors: Kohji Naora, Yoshihiro Katagiri, Nobuhiro Ichikawa, Masakazu Hayashibara, Kikuo Iwamoto
    Abstract:

    — The change in plasma concentration-time profile, serum protein binding and renal and biliary clearances of ciprofloxacin caused by coadministration of Fenbufen has been studied in rats administered an intravenous dose of ciprofloxacin (5 mg kg−1) alone or with Fenbufen (10 mg kg−1). Coadministered Fenbufen significantly prolonged the plasma elimination half-life of ciprofloxacin from 40.5 to 57.6 min and tended to reduce the total body clearance of this quinolone by about 20%. The extent of ciprofloxacin binding to rat serum protein was not affected by Fenbufen, nor did it affect the biliary clearance of the quinolone. However, Fenbufen tended to reduce renal clearance and significantly decreased the cumulative renal excretion of the quinolone during at least the first 3 h after drug administration. These results suggest a possible reduction of ciprofloxacin clearance owing to inhibition of renal excretion by Fenbufen.

  • a minor possibility of pharmacokinetic interaction between enoxacin and Fenbufen in rats
    Journal of pharmacobio-dynamics, 1990
    Co-Authors: Kohji Naora, Yoshihiro Katagiri, Nobuhiro Ichikawa, Masakazu Hayashibara, Kikuo Iwamoto
    Abstract:

    In order to clarify the possibility of pharmacokinetic interaction between quinolone and Fenbufen, the plasma concentration-time profiles and serum protein binding of enoxacin, Fenbufen and its active metabolite, felbinac, were investigated in rats. The rats were administered an intravenous dose of enoxacin (5 mg/kg) and Fenbufen (10 mg/kg) alone or concomitantly. Coadministration with Fenbufen tended to prolong the plasma elimination half-life of enoxacin by about 20%, whereas it showed no effect on the area under plasma concentration-time curve, total body clearance or distribution volume of enoxacin. The extent of enoxacin binding to rat serum tended to be slightly reduced by Fenbufen in vivo and in vitro. Plasma concentration-time curves, pharmacokinetic parameters and serum protein binding of Fenbufen and felbinac were not affected at all by the coadministration with enoxacin. These aspects suggest that there may be only a minor possibility of the pharmacokinetic interaction between enoxacin and Fenbufen.

A Hernanz - One of the best experts on this subject based on the ideXlab platform.

  • structure and vibrational spectroscopy of the Fenbufen β cyclodextrin inclusion complex
    Vibrational Spectroscopy, 2013
    Co-Authors: A Hernanz, Ferenc Billes, Hans Mikosch, Ioan Bratu
    Abstract:

    Abstract The structure and host–guest interactions in the inclusion complex (179 atoms) of β-cyclodextrin with Fenbufen are studied. Fenbufen, the biphenyl derivative γ-oxo-(1,1′-biphenyl)-4-butanoic acid, is a widespread analgesic and non-steroidal anti-inflammatory drug. Its inclusion complex with β-cyclodextrin improves the oral bioavailability and entails fewer side-effects. Optimized molecular structures, atomic net charges and vibrational spectra have been computed for the host and guest molecules, as well as for the inclusion complex. The functional density theory with the B3LYP/3-21+G method/basis set has been applied. The calculated vibrational frequencies have not been scaled, and the simulated spectra have been compared with those obtained experimentally. The host–guest interactions have been investigated in detail.

  • 1h nmr study of the inclusion processes for α and γ cyclodextrin with Fenbufen
    Biopolymers, 2005
    Co-Authors: I Bratu, J M Gaviravallejo, A Hernanz
    Abstract:

    1H-NMR spectra of aqueous solutions of Fenbufen and two cyclodextrins (α- or γ-cyclodextrin, respectively) mixtures confirm the formation of an inclusion complex if γ-cyclodextrin is used, whereas in the case of α-cyclodextrin no inclusion complex was obtained. The stoichiometry of the Fenbufen/γ-cyclodextrin complex is of the [2:1] type. The geometry of this supramolecular architecture was established through MM+ molecular mechanics calculations. © 2005 Wiley Periodicals, Inc. Biopolymers 77: 361–367, 2005

  • inclusion complex of Fenbufen with β cyclodextrin
    Biopolymers, 2004
    Co-Authors: I Bratu, J M Gaviravallejo, A Hernanz, M Bogdan, Gh Bora
    Abstract:

    An inclusion complex of Fenbufen with β-cyclodextrin (β-CD) in aqueous solution was characterized by 1H-NMR spectroscopy. The [1:1] stoichiometry was determined and a stability constant of several 1000s (M−1) was calculated. The geometry of the inclusion complex was established based on MM+ molecular mechanics calculations. © 2004 Wiley Periodicals, Inc. Biopolymers, 2004