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1.
A simple reversed-phase high-performance liquid chromatographic (HPLC) method has been developed for the simultaneous determination
of the antiepileptic drugs (AEDs) zonisamide (ZNS), primidone (PRI), lamotrigine (LTG), phenobarbital (PB), phenytoin (PHT),
oxcarbazepine (OXC), and carbamazepine (CBZ) and two of their active metabolites, monohydroxycarbamazepine (MHD) and carbamazepine
10,11-epoxide (CBZE) in human plasma. Plasma (100 μL) was pretreated by deproteinization with 300 μL methanol containing 20 μg mL−1 propranolol hydrochloride as internal standard. HPLC was performed on a C8 column (4.6 mm × 250 mm; particle size 5 μm) with methanol–acetonitrile–0.1% trifluoroacetic acid, 235:120:645 (v/v), as mobile phase at a flow rate of 1.5 mL min−1. ZNS, OXC, and CBZ were monitored by UV detection at 235 nm, and PRI, LTG, MHD, PB, PHT, and CBZE by UV detection at 215 nm.
Relationships between response and concentration were linear over the concentration ranges 1–80 μg mL−1 for ZNS, 5–50 μg mL−1 for PRI, 1–25 μg mL−1 for LTG, 1–50 μg mL−1 for MHD, 5–100 μg mL−1 for PB, 1–10 μg mL−1 for CBZE, 0.5–25 μg mL−1 for OXC, 1–50 μg mL−1 for PHT, and 1–25 μg mL−1 for CBZ. Intra-day and inter-day reproducibility were adequate (coefficients of variation were ≤11.6%) and absolute recovery
ranged from 95.2 ± 6.13 to 107.7 ± 7.76% for all the analytes; for the IS recovery was 98.69 ± 1.12%. The method was proved
to be accurate, reproducible, convenient, and suitable for therapeutic monitoring of the nine analytes. 相似文献
2.
Differentiation of certified brands of origins of Spanish white wines by HS-SPME-GC and chemometrics 总被引:1,自引:0,他引:1
Jurado JM Ballesteros O Alcázar A Pablos F Martín MJ Vilchez JL Navalón A 《Analytical and bioanalytical chemistry》2008,390(3):961-970
A headspace solid-phase microextraction gas-chromatographic (HS-SPME-GC) procedure was used to determine the composition of
the volatile fraction of white wine samples from several Spanish certified brands of origin (CBO). The compounds present were
previously identified by gas chromatography−mass spectrometry (GC−MS) and quantitative determinations were carried out by
GC-FID. Four CBO, Rueda, Ribeiro, Penedés, and Condado de Huelva, were studied. Rueda wines present the highest concentrations
of ethyl acetate (55.86−125.27 μg mL−1), isoamyl acetate (0.91−6.72 μg mL−1), hexyl acetate (0.09−0.81 μg g mL−1), and 2-phenethyl acetate (0.14−0.66 μg mL−1). Compounds such as ethyl hexanoate (0.88−2.15 μg mL−1) and ethyl decanoate (0.29−0.96 μg mL−1) appeared in higher concentration in Ribeiro, Rueda, and Penedés samples. According to the results obtained and by applying
pattern-recognition procedures differentiation of the considered CBO was attained. Principal-component analysis (PCA), linear
discriminant analysis (LDA), and multilayer perceptrons neural networks (MLP-NN) were used as chemometric tools for pattern-recognition
studies.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
3.
Summary A simple, rapid and accurate, routine-HPLC method is described for simultaneous determination of acetaminophen, caffeine and
chlorpheniramine maleate in a new tablet formulation Chromatographic separation of the three pharmaceuticals was achieved
on a Hypersil CN column (150×5.0 mm, 5 μm) using a mobile phase comprising a mixture of acetonitrile, an ion-pair solution
and tetrahydrofuran (13:14:87, v/v,pH4.5). The flow-rate was changed from 1.0 mL min−1 (in 0≈7.5 min) to 1.8 mL min−1 (after 3.5 min). was complete in <10 min. The method was validated for system suitability, linearity, accuracy, precision,
limits of detection and quantitation, and robustness. Linearity, accuracy and precision were found to be acceptable over the
ranges 31.6≈315.8 μg mL−1 for acetaminophen, 9.5≈94.6 μg mL−1 for caffeine and 1.4≈13.8 μg mL−1 for chlorpheniramine maleate. 相似文献
4.
Wang R Hao H Wang G Xie H Xu M Wang W He H Li X 《Journal of photochemistry and photobiology. B, Biology》2008,90(3):179-186
Deuxemether was a new photodynamic drug effective for many kinds of solid tumor therapy, which was mainly composed of 3-(or 8-)-(1-methoxyethyl)-8-(or 3-)-(1-hydroxyethyl)-deutero-porphyrin IX (MHD) and 3,8-di(1-methoxyethyl)-deuteroporphyrin IX (DMD). The aims of this study were to elucidate its pharmacokinetic characteristics, tissue distribution, plasma protein binding and excretion properties and underlying mechanisms of deuxemether in rats based on the simultaneous determination of MHD and DMD. The pharmacokinetic profiles of both MHD and DMD in rats after intravenous doses were linear and best fitted to a two compartment model, characterized with a rapid distribution phase (MHD: t1/2, 0.09–0.14 h; DMD: t1/2, 0.07–0.11 h) and a relatively slow elimination phase (MHD: t1/2β, 2.03–3.20 h; DMD: t1/2β, 2.51–3.20 h). The tissue distributions of MHD and DMD in rats were rather limited as evidenced from their low distribution volume (0.75–1.70 L/kg) and the results of tissue distribution study. Protein binding of MHD and DMD were moderate (65.36–89.99% for MHD; 45.43–76.23% for DMD), independent of drug concentrations and similar between human and rat plasma over a concentration range of 0.50–50.0 μg/mL. Both MHD and DMD were predominantly (>74.1%) eliminated from rats as the parent drugs through the hepatobiliary systems and finally excreted into the feces. The multidrug resistance-associated proteins 2 (MRP2) inhibitors, bromosulfophthalein and probenecid, substantially inhibited the hepatobiliary elimination of MHD and DMD while the P-gp inhibitor digoxin had little effect, suggesting that MRP2 may contribute to the rapid and extensive hepatobiliary excretion of deuxemether. There were no significant differences between MHD and DMD for all pharmacokinetic characteristics studied. In conclusion, this study provided firstly the full pharmacokinetic characteristics and mechanisms of deuxemether, which would be helpful for its clinical regiment design. 相似文献
5.
A new high-performance liquid chromatography assay was developed for the determination of minocycline in plasma and brain.
A solid–liquid extraction procedure was coupled with a reversed-phase HPLC system. The system requires a mobile phase consisting
of acetonitrile:water:perchloric acid (26:74:0.25, v/v/v) adjusted to pH 2.5 with 5 M sodium hydroxide for elution through a RP8 column (250 × 3.0 mm, i.d.) with UV detection set
at 350 nm. The method proved to be accurate, precise (RSD < 20%) and linear between 0.15–20 μg mL−1 in plasma and 1–20 μg mg−1 in brain. The method was successfully applied to a blood-brain barrier minocycline transport study. 相似文献
6.
A simple, rapid, and precise reversed-phase high-performance liquid chromatographic method has been developed for simultaneous determination of losartan potassium, ramipril, and hydrochlorothiazide. The three drugs were separated on a 150 mm × 4.6 mm i.d., 5 μm particle, Cosmosil C18 column. The mobile phase was 0.025 m sodium perchlorate–acetonitrile, 62:38 (v/v), containing 0.1% heptanesulphonic acid, pH adjusted to 2.85 with orthophosphoric acid, at a flow rate of 1.0 mL min−1. UV detection was performed at 215 nm. The method was validated for linearity, accuracy, precision, and limit of quantitation. Linearity, accuracy, and precision were acceptable in the ranges 35–65 μg mL−1 for losartan, 1.75–3.25 μg mL−1 for ramipril, and 8.75–16.25 μg mL−1 for hydrochlorothiazide. 相似文献
7.
Cantú MD Toso DR Lacerda CA Lanças FM Carrilho E Queiroz ME 《Analytical and bioanalytical chemistry》2006,386(2):256-263
Simple, sensitive, and reproducible off-line solid-phase microextraction and liquid chromatography (SPME/LC) methods are described
for the determination of seven anticonvulsants and tricyclic antidepressants in human plasma. Factorial design and simplex
methodology were applied in the optimization of the SPME procedure for tricyclic antidepressants analyses. Important factors
in the SPME efficiency are discussed, such as the fiber coatings (both lab-made and commercial), extraction time, pH, ionic
strength, influence of plasma proteins, and desorption conditions. The development of the lab-made fiber coatings, namely,
octadecylsilane, aminosilane, and polyurethane, are further described and applied to anticonvulsants analyses. The investigated
plasmatic range for the evaluated anticonvulsants, using CW-TPR fiber, were the following: phenylethylmalonamide (3.00–40.0 μg
mL−1), phenobarbital (5.00–40.0 μg mL−1), primidone (3.00–40.0 μg mL−1), carbamazepine and carbamazepine-epoxide (2.00–24.0 μg mL−1), phenytoin (2.00–40.0 μg mL−1), and lamotrigine (0.50–12.0 μg mL−1). The antidepressants’ linear plasmatic concentration ranged from 75.0 to 500 ng mL−1 for imipramine, amitriptyline, and desipramine, and from 50.0 to 500 ng mL−1 for nortriptyline, being in all cases, the limit of quantification represented by the lowest value. The precision (interassays)
for all investigated drugs in plasma sample spiked with different concentrations of each analyte and submitted to the described
procedures were lower than 15%. The off-line SPME/LC methodologies developed allow anticonvulsants and antidepressants analyses
from therapeutic to toxic levels for therapeutic drug monitoring. 相似文献
8.
Summary A high-performance liquid chromatographic method, with 9-anthryldiazomethane as derivatizing agent, has been developed for
the simultaneous determination ofN-carbamoyl aspartate andl-dihydroorotate in serum. Sample preparation for 1 mL serum was by simple liquid-liquid extraction and then derivatization.
The compounds were separated on a Luna C18(2) column by use of a gradient prepared from acetonitrile and 10 mM sodium acetate
buffer, pH 6.0, and fluorimetric detection was performed at excitation and emission wavelengths of 365 nm and 412 nm, respectively.
The response was found to be linearly dependent on concentration between 0.8 and 60 μg mL−1 forl-dihydrooratate and between 0.9 and 90 μg mL−1 forN-carbamoyl aspartate; the mean recovery rates were 50 and 51%, respectively. The limits of detection and quantification were
0.33 μg mL−1 and 0.6 μg mL−1, respectively, forl-dihydroorotate and 0.4 μg mL−1 and 0.7 μg mL−1 forN-carbamoyl aspartate. This method can be used to assess accumulation ofN-carbamoyl aspartate andl-dihydroorotate in body fluids in situations where cellular pyrimidine de novo synthesis is impaired. 相似文献
9.
E. W. J. Hooijschuur Ch. E. Kientz J. Dijksman U. A. Th. Brinkman 《Chromatographia》2001,54(5-6):295-301
Summary The potential of microcolumn liquid chromatography (μlC) and capillary electrophoresis (CE) with on-line, flame photometric
detection (FPD) in the P-selective mode has been studied for determination of polar P-containing pesticides, glyphosate and
its main metabolite, aminomethylphosphonic acid (AMPA), ethephon, fosetyl-aluminium and acephate. Acephate was determined
by reversed-phase μLLC-FPD using large-volume injections with peak compression, the other compounds were determined by μLC-FPD
and CE-FPD using simple, large-volume injection procedures to obtain limits of detection of 7.5-500 ng·mL−1 and 1.0 μ·mL−1, respectively. The methods showed acceptable repeatability and robustness and were successfully applied for rapid and selective
determination of pesticides in fruit, vegetable and water samples. 相似文献
10.
Summary A rapid and accurate HPLC method is described for the simultaneous determination of acetaminophen, dextromethorphen hydrobromide
and pseudoephedrine hydrochloride in a new cold formulation. Chromatographic separation of the three pharmaceuticals was performed
on a Hypersil CN column (150×5.0 mm, 5 μm) with a mobile phase mixture of an ion-pairing solution, methanol and acetonitrile
(25:57:18, v/v), at a flow rate of 1.0 mL min−1, with detection at 220 nm. Separation was complete in less than 10 min. The method was validated for linearity, accuracy,
precision, limit of quantitation and robustness. Linearity, accuracy, and precision were found to be acceptable over the ranges
of 2.06∼20.6 μg·mL−1 for acetaminophen, 0.202∼2.02 mg·mL−1 for pseudoephedrine hydrochloride and 0.042∼1.06 mg·mL−1 for dextromethorphen hydrobromide. 相似文献
11.
Summary A simple and rugged SPE method for the determination of tetracycline (TC), minocycline (MC) and demeclocycline (DCC) in porcine
serum by high performance liquid chromatography (HPLC) was developed. The spiked serum sample was pretreated with 2% phosphoric
acid followed by a simple and rugged solid-phase extraction procedure using the OasisTM HLB extraction cartridges. High and reproducible recoveries were obtained even though the cartridges were run dry. The extracted
sample analytes were injected onto a Waters SymmetryShieldTM RP8 column. The mobile phase was a simple volatile solution containing 0.1% TFA, 2% methanol and 7% acetonitrile in Water. The
antibiotics were detected at 350 nm. The calibration curves were linear from 2.0 to 25.0 μg mL−1 of TC and MC with DCC as the internal standard at a concentration of 25.0 μg mL−1. For six replicate analyses, the average recoveries of TC and MC from porcine serum sample fortified at the level of 2.5
μg mL−1 were 96.1% with 1.3% RSD and 101% with 0.54% RSD; at level of 0.5 μg mL−1 the average recoveries were 88% with 1.6% RSD and 97.8% with 1.4% RSD. 相似文献
12.
M. A. Campanero A. M. Zamarreño M. Simón M. C. Dios J. R. Azanza 《Chromatographia》1997,46(7-8):374-380
Summary A simple and rapid liquid chromatographic method has been developed for the determination of therapeutic levels of piperacillin
(I) and ceftazidime (II) in human plasma. Plasma and p-propionamidophenol (internal standard) were precipitated with methanol
(I) or 20% trichloroacetic acid (II). The supernatant was analysed on a 5 μm Spherisorb ODS C18 column with acetonitrile-0.05 M phosphate buffer pH 3.8 as mobile phase and ultraviolet detection at 254 nm. The calibration
graph was linear from 10 to 250 μg mL−1, for (I), and from 5 to 200 μg mL−1 for (II). Intra and inter-day CV did no exceed 2.29% for (I), and were 10.76–11.13%–2.00–5.62 for (II) at concentrations
of 10 μg mL−1 and 250 μg mL−1. 相似文献
13.
Tetracycline antibiotics (TCs) such as doxycycline (DOTC), chlortetracycline (CTC), oxytetracycline (OTC), and tetracycline
(TC) react with Cu(II) in pH 3.5 BR buffer medium to form 1:1 cationic chelates, which further react with titan yellow to
form 2:1 ion association complexes. These result in great enhancement of resonance Rayleigh scattering (RRS) and the appearance
of new RRS spectra. The ion association complexes of DOTC, CTC, OTC, and TC have similar spectral characteristics and their
maximum RRS wavelengths are all located at 464 nm. The quantitative determination ranges and the detection limits (3σ) of the four TCs are 0.037–4.8 μg mL−1 and 11.2 ng mL−1 for DOTC, 0.041–5.2 μg mL−1 and 12.4 ng mL−1 for CTC, 0.050–4.8 μg mL−1 and 15.1 ng mL−1 for TC, and 0.088–5.0 μg mL−1 and 26.3 ng mL−1 for OTC, respectively. The optimum reaction conditions, the effects of foreign substances, the structure of ternary complexes,
and the reaction mechanism are discussed. A sensitive, rapid, and simple RRS method for the determination of DOTC has been
developed. 相似文献
14.
A novel method for the determination of paralytic shellfish poisoning (PSP) toxins using high-performance liquid chromatography
with fluorescence detection was developed. The fluorescent derivates of neosaxitoxin (neoSTX), saxitoxin (STX), gonyautoxins
1 and 4 (GTX1+4), and gonyautoxins 2 and 3 (GTX2+3) were separated on a μBondapak NH2 column (300 mm × 3.9 mm, 10 μm) using water and acetate buffer (pH 6.5) as the mobile phase (1.00 mL min−1) in gradient mode with fluorescence detection at 390 nm (excitation at 330 nm). The linear ranges of neoSTX, STX, GTX1+4
and GTX2+3 were 3.31–331, 0.952–95.2, 3.78–378 and 0.124–12.4 ng mL−1, respectively. The detection limits of neoSTX, STX, GTX1+4 and GTX2+3 were 1.10, 0.32, 1.26 and 0.041 ng mL−1, respectively. The method was successfully applied to the determination of PSP toxins in microalgae. The recoveries ranged
from 88±2% to 107±4% and the relative standard deviations were 0.16% to 4.4%. The procedure is also environmentally friendly
because no organic solvent is used in the mobile phase. 相似文献
15.
Dolores Barranco Martínez María Martínez Galera Piedad Parrilla Vázquez M. Dolores Gil García 《Chromatographia》2007,66(7-8):533-538
Liquid chromatography with electrospray mass spectrometry (LC–ESI-MS) instrumentation equipped with a single quadrupole mass
filter has been used to determine several benzoylphenylurea insecticides (diflubenzuron, triflumuron, hexaflumuron, lufenuron
and flufenoxuron). Chromatographic and MS parameters were optimised to obtain the best sensitivity and selectivity for all
pesticides. Solid-phase extraction (SPE) using C18 cartridges was applied for preconcentration of pesticide trace levels in river water samples. Recoveries of benzoylphenylurea
pesticides from spiked river water (0.01 and 0.025 μg L−1) were between 73 and 110% and detection limits were between 3.5 and 7.5 ng L−1. The applicability of the method to the determination of benzoylphenylurea insecticides in spiked cucumber, green beans,
tomatoes and aubergines was evaluated. Samples were extracted into dichloromethane without any clean-up step. The limits of
detection ranged from 1.0 to 3.2 ng mL−1 (0.68 and 2.13 μg kg−1 in the vegetable samples). Mean recoveries ranged from 79 to 114% at spiking levels of 0.01 and 0.03 mg kg−1. The method was applied to determine traces of benzoylphenylureas in both river water and vegetable samples with precision
values lower than 10%. Interferences due to the matrix effect were overcome using matrix-matched standards. 相似文献
16.
Summary A novel method for the simultaneous determination of twelve water- and fat-soluble vitamins has been established by high-performance
liquid chromatography with diode array detection. The vitamins were analyzed on a μBondapak C18 column (300 × 3.9 mm, 10 μm) with methanol-KH2PO4 buffer (0.1 M, pH 7.0)-water as mobile phase in a gradient. The linearity of calibration graphs was compound-dependent and
the detection limits ranged from 0.02 μg mL−1 to 0.5 μg mL−1. The method was successfully applied to determine vitamins in pharmaceutical preparations. The recoveries were from 95.1%
to 103% and the relative standard deviations were in the range of 0.9% to 4.5%. 相似文献
17.
A new method was developed for the simultaneous determination of lidocaine, proline and lomefloxacin in human urine by capillary
electrophoresis-electrochemiluminescence detection with Ru(bpy)3
2+. Conditions of the separation and detection were investigated and optimized. It was proved that 20 mM phosphate buffer at
pH 6.7 could achieve the most favorable resolution, and the high sensitivity of detection was obtained by using the detection
potential at 1.15 V and 5 mM Ru(bpy)3
2+–60 mM phosphate buffer at pH 7.6 in the detection reservoir. The detection limits were 0.02 μg mL−1 for lidocaine, 0.03 μg mL−1 for proline and 0.06 μg mL−1 for lomefloxacin. Relative standard deviations of the ECL intensity and the migration time were 3.5 and 1.1% for 6 μg mL−1 lidocaine, 3.2 and 1.0% for 6 μg mL−1 proline and 3.7 and 1.2% for 6 μg mL−1 lomefloxacin, respectively. A baseline separation for lidocaine, proline and lomefloxacin was achieved within 360 s. The
developed method was successfully applied to determine the amounts of lidocaine, proline and lomefloxacin in human urine.
The recovery and RSD were in the range of 93.3–97.2 and 3.8–4.9%, respectively. 相似文献
18.
Determination of Aldehydes and Ketones in Fuel Ethanol by High-Performance Liquid Chromatography with Electrochemical Detection 总被引:1,自引:0,他引:1
A. A. Saczk L. L. Okumura M. F. de Oliveira M. V. B. Zanoni N. R. Stradiotto 《Chromatographia》2006,63(1-2):45-51
A new methodology was developed for analysis of aldehydes and ketones in fuel ethanol by high-performance liquid chromatography
(HPLC) coupled to electrochemical detection. The electrochemical oxidation of 5-hydroxymethylfurfural, 2-furfuraldehyde, butyraldehyde,
acetone and methyl ethyl ketone derivatized with 2,4-dinitrophenylhydrazine (DNPH) at glassy carbon electrode present a well
defined wave at +0.94 V; +0.99 V; +1.29 V; +1.15 V and +1.18 V, respectively which are the basis for its determination on
electrochemical detector. The carbonyl compounds derivatized were separated by a reverse-phase column under isocratic conditions
with a mobile phase containing a binary mixture of methanol / LiClO4(aq) at a concentration of 1.0 × 10−3 mol L−1 (80:20 v/v) and a flow-rate of 1.1mL min−1 . The optimum potential for the electrochemical detection of aldehydes-DNPH and ketones-DNPH was +1.0 V vs. Ag/AgCl. The
analytical curve of aldehydes-DNPH and ketones-DNPH presented linearity over the range 5.0 to 400.0 ng mL−1, with detection limits of 1.7 to 2.0 ng mL−1 and quantification limits from 5.0 to 6.2 ng mL−1, using injection volume of 20 μL. The proposed methodology was simple, low time-consuming (15 min/analysis) and presented
analytical recovery higher than 95%. 相似文献
19.
Capitán-Vallvey LF Valencia MC Arana Nicolás E García-Jiménez JF 《Analytical and bioanalytical chemistry》2006,385(2):385-391
An integrated solid-phase spectrophotometry–FIA method is proposed for simultaneous determination of the mixture of saccharin
(1,2-benzisothiazol-3(2H)-one-1,1-dioxide; E-954) (SA) and aspartame (N-l-α-aspartyl-l-phenylalanine-1-methyl ester; E-951) (AS). The procedure is based on on-line preconcentration of AS on a C18 silica gel minicolumn and separation from SA, followed by measurement, at λ=210 nm, of the absorbance of SA which is transiently retained on the adsorbent Sephadex G-25 placed in the flow-through cell
of a monochannel FIA setup using pH 3.0 orthophosphoric acid–dihydrogen phosphate buffer, 3.75×10–3 mol L−1, as carrier. Subsequent desorption of AS with methanol enables its determination at λ=205 nm. With a sampling frequency of 10 h−1, the applicable concentration range, the detection limit, and the relative standard deviation were from 1.0 to 200.0 μg mL−1, 0.30 μg mL−1, and 1.0% (80 μg mL−1, n=10), respectively, for SA and from 10.0 to 200.0 μg mL−1, 1.4 μg mL−1, and 1.6% (100 μg mL−1, n=10) for AS. The method was used to determine the amounts of aspartame and saccharin in sweets and drinks. Recovery was always
between 99 and 101%. The method enabled satisfactory determination of blends of SA and AS in low-calorie and dietary products
and the results were compared with those from an HPLC reference method. 相似文献
20.
A novel kinetic spectrofluorimetric method for the determination of uric acid based on the activation effect of uric acid
on the Cu(II) ion catalyzed oxidation of pyronine Y by hydrogen peroxide was developed. The influence of different buffer
solutions was tested and the Britton-Robinson buffer solution with pH 2.2 was found to be the optimum. The detection limit
and the linear range for uric acid are 0.09 μg mL−1 and 0.3–3.0 μg mL−1, respectively. The RSD for eleven determinations of 1.6 μg mL−1 uric acid was 1.6 %. Satisfactory results were obtained when using this method of uric acid determination in human urine. 相似文献