共查询到20条相似文献,搜索用时 31 毫秒
1.
Minakata K Nozawa H Gonmori K Yamagishi I Suzuki M Hasegawa K Watanabe K Suzuki O 《Analytical and bioanalytical chemistry》2011,400(7):1945-1951
An electrospray ionization tandem mass spectrometric (ESI-MS-MS) method has been developed for the determination of cyanide
(CN–) in blood. Five microliters of blood was hemolyzed with 50 μL of water, then 5 μL of 1 M tetramethylammonium hydroxide solution
was added to raise the pH of the hemolysate and to liberate CN– from methemoglobin. CN– was then reacted with NaAuCl4 to produce dicyanogold, Au(CN)2–, that was extracted with 75 μL of methyl isobutyl ketone. Ten microliters of the extract was injected directly into an ESI-MS-MS
instrument and quantification of CN– was performed by selected reaction monitoring of the product ion CN– at m/z 26, derived from the precursor ion Au(CN)2– at m/z 249. CN– could be measured in the quantification range of 2.60 to 260 μg/L with the limit of detection at 0.56 μg/L in blood. This
method was applied to the analysis of clinical samples and the concentrations of CN– in the blood were as follows: 7.13 ± 2.41 μg/L for six healthy non-smokers, 3.08 ± 1.12 μg/L for six CO gas victims, 730 ± 867 μg
for 21 house fire victims, and 3,030 ± 97 μg/L for a victim who ingested NaCN. The increase of CN– in the blood of a victim who ingested NaN3 was confirmed using MS-MS for the first time, and the concentrations of CN– in the blood, gastric content and urine were 78.5 ± 5.5, 11.8 ± 0.5, and 11.4 ± 0.8 μg/L, respectively. 相似文献
2.
Precht JC Ganchev B Heinkele G Brauch H Schwab M Mürdter TE 《Analytical and bioanalytical chemistry》2012,403(1):301-308
Letrozole is an efficient endocrine treatment of postmenopausal breast cancer, however, not all patients benefit from this
treatment, and moreover, severe side-effects like arthralgia frequently lead to discontinuation. To better understand inter-individual
variability in drug response and side-effects, plasma analysis of steady-state concentrations of letrozole and its major metabolites
is crucial. We developed a rapid, sensitive, and specific method for the simultaneous quantification of letrozole and its
metabolites 4,4′-(hydroxymethylene)dibenzonitrile (carbinol) and bis(4-cyanophenyl)methyl hexopyranosiduronic acid (carbinol-gluc)
by UHPLC-ESI-MS/MS using in-house synthesized, stable isotope-labeled internal standards. Following solid-phase extraction
in BondElut C18 96-well plates, the analytes were separated on a ZORBAX Eclipse XDB-C18 column (1.8 μm, 4.6 × 50 mm) with
a gradient of acetonitrile in 0.1% acetic acid in water and detected on a triple quadrupole mass spectrometer with electrospray
ionization in the multiple reaction monitoring mode. Lower limits of quantification were 20, 0.2, and 2 nM for letrozole,
carbinol, and carbinol-gluc, respectively. The assay has been validated according to FDA guidance and applied to the analysis
of 20 plasma samples of postmenopausal breast cancer patients treated with 2.5 mg of letrozole per day. Mean plasma levels
(±SD) were 366 ± 173, 0.38 ± 0.09, and 34 ± 12 nM for letrozole, carbinol, and carbinol-gluc, respectively. Our rapid and
sensitive mass spectrometry based method enables future pharmacokinetic investigations of letrozole outcome. 相似文献
3.
Leonhard Jaitz Bernhard Mueller Gunda Koellensperger Daniela Huber Eva Oburger Markus Puschenreiter Stephan Hann 《Analytical and bioanalytical chemistry》2011,400(8):2587-2596
A sensitive method for quantification of citric, fumaric, malic, malonic, oxalic, trans aconitic, and succinic acid in soil-
and root-related samples is presented. The method is based on a novel, fast, and simple esterification procedure and subsequent
analysis via liquid chromatography–mass spectrometry. Derivatization comprises in situ generation of HCl, which catalyzes
the Fischer esterification with benzyl alcohol. As a key advance, the esterification with the aromate allows reversed-phase
separation and improves electrospray ionization efficiency. The method provided procedural detection limits of 1 nM for citric,
47 nM for fumaric, 10 nM for malic, 10 nM for malonic, 16 nM for oxalic, 15 nM for succinic, and 2 nM for aconitic acid utilizing
500 μL of liquid sample. The working range was 3 nM to 10 μM for citric acid, 158 nM to 10 μM for fumaric acid, 34 nM to 10 μM
for malic acid, 33 nM to 10 μM for malonic acid, 53 nM to 10 μM for oxalic acid, 48 nM to 10 μM for succinic acid, and 6 nM
to 10 μM for aconitic acid. Quantification of the analytes in soil-related samples was performed via external calibration
of the entire procedure utilizing 13C-labeled oxalic and citric acid as internal standards. The robustness of the method was tested with soil extracts and samples
from hydroponic experiments. The latter concerned the regulation of phosphorus solubilization via plant root exudation of
citric, malic, and oxalic acid. 相似文献
4.
Liu X Xu J Li Y Dong F Li J Song W Zheng Y 《Analytical and bioanalytical chemistry》2011,399(7):2539-2547
A sensitive and effective method for simultaneous determination of triazolopyrimidine sulfonamide herbicide residues in soil,
water, and wheat was developed using ultra-performance liquid chromatography coupled with tandem mass spectrometry. The four
herbicides (pyroxsulam, flumetsulam, metosulam, and diclosulam) were cleaned up with an off-line C18 SPE cartridge and detected
by tandem mass spectrometry using an electrospray ionization source in positive mode (ESI+). The determination of the target
compounds was achieved in <2.0 min. The limits of detection were below 1 μg kg−1, while the limits of quantification did not exceed 3 μg kg−1 in different matrices. Quantitation was determined from calibration curves of standards containing 0.05–100 μg L−1 with r
2 > 0.997. Recovery studies were conducted at three spiked levels (0.2, 1, and 5 μg kg−1 for water; 5, 10, and 100 μg kg−1 for soil and wheat). The overall average recoveries for this method in water, soil, wheat plants, and seeds at three levels
ranged from 75.4% to 106.0%, with relative standard deviations in the range of 2.1–12.5% (n = 5) for all analytes. 相似文献
5.
The opioid tilidine is a prodrug which is hepatically metabolized to active nortilidine and bisnortilidine. Due to the increasing
abuse of tilidine by drug users and the lack of a specific immunoassay, we developed an analytical method for the quantification
of tilidine, nortilidine, and bisnortilidine in urine suitable for screening. In a following step, this method was used to
establish data on excretion kinetics of the substances in order to evaluate the time window of detection after a single oral
dose of tilidine/naloxone and also was applied to authentic urine samples from correctional facilities. Urine samples were
mixed with internal standard solution and extracted on a weak cation exchanger at pH 6 using a Symbiosis Pico system. The
chromatographic separation was achieved within a 3.5-min run time on a Phenylhexyl column (50 × 2.0 mm, 5 μm) via gradient
elution (methanol and 0.2% formic acid) at a flow rate of 0.50 mL/min. The ESI-MS/MS was performed on a QTrap 3,200 in positive
multiple reaction monitoring mode using two mass transitions per analyte. Validating the method resulted in a lower limit
of quantification of 1.0 μg/L followed by a linear calibration range to 100 μg/L for each analyte (r
2 > 0.99). The analytical method allowed the detection of a single dose of a commercially available tilidine solution up to
7 days after administration. Using this highly sensitive method, 55 of 3,665 urine samples were tested positive. 相似文献
6.
Chang-Ching Lin Chien-Wen Kuo Li-Heng Pao 《Analytical and bioanalytical chemistry》2010,398(2):857-865
The first liquid chromatography–tandem mass spectrometry method was developed and validated for the simultaneous quantification
of p-aminohippuric acid and inulin, both typical biomarkers of kidney function. 5-(Hydroxymethyl)furfural, generated from inulin
by acid and heat preparation, was used as an inulin substitute for the quantification. Acetaminophen was used as the internal
standard. Solid-phase extraction was carried out with 5% methanol as the washing solution to optimize the retention of the
analytes and to avoid obstruction of the orifice plate of the mass spectrometer caused by any unreacted inulin residue remaining
from the sample preparation process. Chromatography separation was performed on a Symmetry C18 column and a mobile phase composed of 2 mM ammonium formate and 0.1% formic acid in water (solvent A) and 2 mM ammonium formate
and 0.1% formic acid in acetonitrile (solvent B) (30:70, v/v). Detection was performed with a triple-quadrupole tandem mass
spectrometer using positive ion mode electrospray ionization in the multiple reaction monitoring mode. The selected transitions
were m/z 195.2 → 120.2, 127.1 → 109.1, and 152.1 → 110.0 for p-aminohippuric acid, inulin [measured as 5-(hydroxymethyl)furfural], and acetaminophen, respectively. The linearity ranged
from 10 to 140 μg/mL and from 100 to 1,400 μg/mL for p-aminohippurric acid and inulin (r > 0.99), respectively. The precisions and accuracies were all within 12 and 11% for the lower limit of quantification and
quality control samples, respectively. This application was proven to be reliable and accurate and was successfully applied
to a renal function study. 相似文献
7.
Evaluation of a novel ELISA for serotonin: urinary serotonin as a potential biomarker for depression
Nichkova MI Huisman H Wynveen PM Marc DT Olson KL Kellermann GH 《Analytical and bioanalytical chemistry》2012,402(4):1593-1600
Depression is a common disorder with physical and psychological manifestations often associated with low serotonin. Since
noninvasive diagnostic tools for depression are sparse, we evaluated the clinical utility of a novel ELISA for the measurement
of serotonin in urine from depressed subjects and from subjects under antidepressant therapy. We developed a competitive ELISA
for direct measurement of serotonin in derivatized urine samples. Assay performance was evaluated and applied to clinical
samples. The analytical range of the assay was from 6.7 to 425 μg serotonin/g creatinine (Cr). The limit of quantification
was 4.7 μg/g Cr. The average recovery for spiked urine samples was 104.4%. Average intra-assay variation was 4.4%, and inter-assay
variation was <20%. The serotonin analysis was very specific. No significant interferences were observed for 44 structurally
and nonstructurally related urinary substances. Very good correlation was observed between urinary serotonin levels measured
by ELISA and liquid chromatography tandem mass spectrometry (LC-MS/MS; ELISA = 1.16 × LC-MS/MS − 53.8; r = 0.965; mean % bias = 11%; n = 18). Serotonin was stable in acidified urine for 30 days at room temperature and at −20 °C. The established reference range
for serotonin was 54–366 μg/g Cr (n = 64). Serotonin levels detected in depressed patients (87.53 ± 4.89 μg/g Cr; n = 60) were significantly lower (p < 0.001) than in nondepressed subjects (153.38 ± 7.99 μg/g Cr). Urinary excretion of serotonin in depressed individuals significantly
increased after antidepressant treatment by 5-hydroxy-tryptophane and/or selective serotonin re-uptake inhibitor (p < 0.01). The present ELISA provides a convenient and robust method for monitoring urinary serotonin. It is suitable to monitor
serotonin imbalances and may be particularly helpful in evaluating antidepressant therapies. 相似文献
8.
Wilhelmina H. A. de Jong Marianne H. L. I. Wilkens Elisabeth G. E. de Vries Ido P. Kema 《Analytical and bioanalytical chemistry》2010,396(7):2609-2616
Serotonin emerges as crucial neurotransmitter and hormone in a growing number of different physiologic processes. Besides
extensive serotonin production previously noted in patients with metastatic carcinoid tumors, serotonin now is implicated
in liver cell regeneration and bone formation. The aim was to develop a rapid, sensitive, and highly selective automated on-line
solid-phase extraction method coupled to high-performance liquid chromatography–tandem mass spectrometry (XLC-MS/MS) to quantify
low serotonin concentrations in matrices such as platelet-poor plasma and urine. Fifty microliters plasma or 2.5 μL urine
equivalent were pre-purified by automated on-line solid-phase extraction, using weak cation exchange. Chromatography of serotonin
and its deuterated internal standard was performed with hydrophilic interaction chromatography. Mass spectrometric detection
was operated in multiple reaction monitoring mode using a quadrupole tandem mass spectrometer with positive electrospray ionization.
Serotonin concentrations were determined in platelet-poor plasma of metastatic carcinoid patients (n = 23) and healthy controls (n = 22). Urinary reference intervals were set by analyzing 24-h urine collections of 120 healthy subjects. Total run-time was
6 min. Intra- and inter-assay analytical variation were <10%. Linearity in the 0–7300 μmol/L calibration range was excellent
(R2 > 0.99). Quantification limits were 30 and 0.9 nmol/L in urine and plasma, respectively. Platelet-poor serotonin concentrations
in metastatic carcinoid patients were significantly higher than in controls. The urinary reference interval was 10–78 μmol/mol
creatinine. Serotonin analysis with sensitive and specific XLC-MS/MS overcomes limitations of conventional HPLC. This enables
accurate quantification of serotonin for both routine diagnostic procedures and research in serotonin-related disorders. 相似文献
9.
Christina Schiborr Gunter P. Eckert Gerald Rimbach Jan Frank 《Analytical and bioanalytical chemistry》2010,397(5):1917-1925
Curcumin, a lipophilic polyphenol derived from the rhizome of the plant turmeric (Curcuma longa), might be useful in the prevention and treatment of a number of degenerative brain disorders, including glioma multiforma
and Alzheimer’s disease. Thus, there is growing interest in measuring curcumin concentrations in the brain and other target
tissues in relevant animal models. We therefore developed and validated (according to the Food and Drug Administration guidelines
for bioanalytical method validation), a simple, fast and reliable method for the quantification of curcumin in biological
matrices by fast high-performance liquid chromatography with fluorescence detection. This method involves a simple extraction
with 95% ethyl acetate and 5% methanol, rapid separation (<2 min if external standards and <4 min if the internal standard
β-estradiol 17-acetate is used) on a Jasco Reprosil-Pur Basic C18 column (75 × 2 mm, 1.8 μm) with an eluent of acetonitrile, methanol, de-ionised water and acetic acid (49:20:30:1, v/v; flow rate, 0.4 mL/min) and fluorescence detection (excitation wavelength, 420 nm; emission wavelength, 470 nm). The method
is selective, precise (<15% RSD at the lower limit of quantification), accurate (<15% of the coefficient of variation at the
lower limit of quantification) and sensitive over a linear range of 0.05–10 μg/mL for curcumin. The developed method was used
for the quantification of curcumin in the brains of mice force-fed (50 mg/kg bw) or i.p. injected (100 mg/kg bw) with curcumin.
Brain curcumin concentrations of the mice were below the limit of detection at 30, 60 and 120 min after oral gavage and reached
4–5 μg/g brain 20–40 min after i.p. injection. In conclusion, the developed and validated method should be useful for the
accurate and precise quantification of curcumin in target organs from relevant animal models of human diseases. 相似文献
10.
Mazzucchelli I Rapetti M Fattore C Franco V Gatti G Perucca E 《Analytical and bioanalytical chemistry》2011,401(3):1013-1021
The development of a simple and rapid high-performance liquid chromatography (HPLC) method for the determination of the new
antiepileptic drug rufinamide (RFN) in human plasma and saliva is reported. Samples (250 μl) are alkalinized with ammonium
hydroxide (pH 9.25) and extracted with dichloromethane using metoclopramide as internal standard. Separation is achieved with
a Spherisorb silica column (250 × 4.6 mm i.d., 5 μm) at 30 °C using as mobile phase a solution of methanol/dichloromethane/n-hexane
10/25/65 (vol/vol/vol) mixed with 6 ml ammonium hydroxide. The instrument used was a Shimadzu LC-10Av chromatograph and flow
rate was 1.5 ml min-1, with a LaChrom L-7400 UV detector set at 230 nm. Calibration curves are linear [r
2 = 0.998 ± 0.002 for plasma (n = 10) and r
2 = 0.999 ± 0.001 for saliva (n = 9)] over the range of 0.25–20.0 μg ml-1, with a limit of quantification at 0.25 μg ml-1. Precision and accuracy are within current acceptability standards. The assay is suitable for pharmacokinetic studies in
humans and for therapeutic drug monitoring. 相似文献
11.
Martínez-Uroz MA Mezcua M Belmonte Valles N Fernández-Alba AR 《Analytical and bioanalytical chemistry》2012,402(3):1365-1372
A gas chromatography–mass spectrometry method in negative chemical ionization mode has been developed incorporating simultaneous
detection using a micro-electron capture detector (μ-ECD) for the determination of pesticides in fruits and vegetables. This
instrument configuration uses a three-way splitter device which divides the effluent from the analytical column between the
two detectors with the split ratio 1:0.1 (MSD/μ-ECD) in each run. The μ-ECD was used for confirmation purposes. Validation
of the method was performed on three matrices: tomato, apple, and orange. The ethyl acetate method was assayed; recovery studies
were performed at 10 and 100 μg/kg. Recoveries between 70% and 120% were achieved and relative standard deviations lower than
20% (n = 5) were obtained for all pesticides and matrices studied. Limits of quantification lower than 10 μg/kg were obtained for
100% of pesticides in all of the matrices. Limits of quantification lower than 2.5 μg/kg were achieved for 77.8% of pesticides
in the tomato and apple matrices, and for 72.2% of pesticides in the orange matrix. The method showed linear response in the
concentration range tested (2.5–500 μg/kg) with correlation coefficients >0.99. Good repeatability and reproducibility results
were obtained in all cases, with relative standard deviations lower than 16.7% and 20%, respectively. Finally, 20 incurred
samples were analyzed using the proposed method. The simultaneous use of the two detectors was satisfactory for the analysis
of these real samples. The total number of pesticides identified was 25. The number of samples which contained at least one
pesticide was 15—this represented 75% of the total number of samples studied. 相似文献
12.
Robert O Sabatier J Desoubzdanne D Lalande J Balayssac S Gilard V Martino R Malet-Martino M 《Analytical and bioanalytical chemistry》2011,399(2):987-999
The aim of this study was to define the optimal pH for 1H nuclear magnetic resonance (NMR) spectroscopy analysis of perchloric acid or methanol–chloroform–water extracts from brain
tumor cells and tissues. The systematic study of the proton chemical shift variations as a function of pH of 13 brain metabolites
in model solutions demonstrated that recording 1H NMR spectra at pH 10 allowed resolving resonances that are overlapped at pH 7, especially in the 3.2–3.3 ppm choline-containing-compounds
region. 1H NMR analysis of extracts at pH 7 or 10 showed that quantitative measurements of lactate, alanine, glutamate, glutamine (Gln),
creatine + phosphocreatine and myo-inositol (m-Ino) can be readily performed at both pHs. The concentrations of glycerophosphocholine,
phosphocholine and choline that are crucial metabolites for tumor brain malignancy grading were accurately measured at pH
10 only. Indeed, the resonances of their trimethylammonium moieties are cleared of any overlapping signal, especially those
of taurine (Tau) and phosphoethanolamine. The four non-ionizable Tau protons resonating as a singlet in a non-congested spectral
region permits an easier and more accurate quantitation of this apoptosis marker at pH 10 than at pH 7 where the triplet at
3.43 ppm can be overlapped with the signals of glucose or have an intensity too low to be measured. Glycine concentration
was determined indirectly at both pHs after subtracting the contribution of the overlapped signals of m-Ino at pH 7 or Gln
at pH 10. 相似文献
13.
Byrdwell WC 《Analytical and bioanalytical chemistry》2011,401(10):3317-3334
A method is demonstrated for analysis of vitamin D fortified dietary supplements that eliminates virtually all chemical pretreatment
prior to analysis, which is referred to as a “dilute-and-shoot” method. Three mass spectrometers, in parallel, plus a UV detector,
an evaporative light-scattering detector (ELSD), and a corona charged aerosol detector (CAD) were used to allow a comparison
of six detectors simultaneously. Ultraviolet data were analyzed using internal standard, external standard, and response factor
approaches. The contents of gelcaps that contained 2,000 IU (50 μg) vitamin D3 in rice bran oil, diluted to 100 mL, were analyzed without the need for lengthy saponification and extraction. Vitamin D3 was analyzed using UV detection, extracted ion chromatograms, selected ion monitoring (SIM) atmospheric pressure chemical
ionization mass spectrometry (APCI-MS), and two transitions of multiple reaction monitoring (MRM) APCI-MS. The internal standard,
external standard, and response factor methods gave values of 0.5870 ± 0.0045, 0.5893 ± 0.0041, and 0.5889 ± 0.0045 μg/mL,
respectively, by UV detection. The values obtained by MS were 0.6117 ± 0.0140, 0.6018 ± 0.0244, and 0.5848 ± 0.0146 μg/mL
by SIM and two transitions of MRM, respectively. The triacylglycerols in the oils were analyzed using full-scan APCI-MS, electrospray
ionization (ESI) MS, up to MS4, an ELSD, and a CAD. The method proved to be very sensitive for vitamin D3, as well as triacylglycerols (TAGs), allowing identification of intact TAGs containing fatty acids up to 28 carbons in length.
LC-ESI-MS of glycerin polymers is also demonstrated. 相似文献
14.
The electrochemical solid phase micro-extraction of salicylic acid (SA) at graphite-epoxy-composed solid electrode surface
was studied by cyclic voltammetry. SA was oxidized electrochemically in pH 12.0 aqueous solution at 0.70 V (vs. saturated
calomel electrode) for 7 s. The oxidized product shows two surface-controlled reversible redox couples with two proton transferred
in the pH range of 1.0∼6.0 and one proton transferred in the pH range of 10.0∼13.0 and is extracted on the electrode surface
with a kinetic Boltzman function of i
p = 3.473–4.499/[1 + e(t − 7.332)/6.123] (χ
2 = 0.00285 μA). The anodic peak current of the extracted specie in differential pulse voltammograms is proportional to the
concentration of SA with regression equation of i
p = −5.913 + 0.4843 c (R = 0.995, SD = 1.6 μA) in the range of 5.00∼200 μM. The detection limit is 5.00 μM with RSD of 1.59% at 60 μM. The method
is sensitive and convenient and was applied to the detection of SA in mouse blood samples with satisfactory results. 相似文献
15.
Hadi Beitollahi Jahan-Bakhsh Raoof Hassan Karimi-Maleh Rahman Hosseinzadeh 《Journal of Solid State Electrochemistry》2012,16(4):1701-1707
This paper reports the selective determination of isoproterenol (IP) in the presence of uric acid (UA) and folic acid (FA)
using 2,7-bis(ferrocenyl ethyl)fluoren-9-one modified carbon nanotube paste electrode (2,7-BFCNPE) in 0.1 M phosphate buffer
solution (PBS) (pH 7.0). The bare carbon paste electrode does not separate the voltammetric signals of IP, UA, and FA. However,
2,7-BFCNPE not only resolved the voltammetric signals of IP, UA, and FA with potential differences of 150, 325, and 475 mV
between IP–UA, UA–FA, and IP–FA, respectively, but also dramatically enhanced the oxidation peak currents of them when compared
to bare carbon paste electrode. In PBS of pH 7.0, the oxidation current increased linearly with two concentration intervals
of IP, one is 0.08 to 17.5 μM and the other is 17.50 to 700.0 μM. The detection limit (3σ) obtained by DPV was 26.0 ± 2 nM. The practical application of the modified electrode was demonstrated by determining IP
in IP injection, urine, and human blood serum. 相似文献
16.
Hua Wei Jun Wen Rui Xie Houwen Lin Guorong Fan Yutian Wu 《Analytical and bioanalytical chemistry》2009,395(5):1461-1469
A sensitive liquid chromatography-tandem mass spectrometry (LC-MS/MS) method, followed by a 96-well protein precipitation,
has been developed and fully validated for the determination of Phakellistatin 13 (PK13), a new cyclic heptapeptide isolated
from the sponge Phakellia fusca Thiele, in rat plasma. After protein precipitation of the plasma samples (50 μL) in a 96-well plate by methanol (200 μL)
containing the internal standard Pseudostellarin B (20 ng/mL), the plate was vortex mixed for 3 min. Following filtration
for 5 min, the filtrate was directly injected into the LC-MS/MS system. The analytes were separated on an XB-C18 analytical
column (5 μm, 50 mm × 4.6 mm i.d.) using an eluent of methanol–water (85:15, v/v) and detected by electrospray ionization mass spectrometry in the negative multiple reaction monitoring mode with a chromatographic
run time of 5.0 min. The method was sensitive with a lower limit of quantification (LLOQ) of 0.1 ng/mL, with good linearity
(r > 0.999) over the quantitation range of 0.1–5 ng/mL. The validation results demonstrated that this method was significantly
specific, accurate, precise, and was successfully applied in measuring levels of PK13 in rat plasma following intravenous
administration of 20, 50, and 100 μg/kg of peptide in rats, respectively, which was suitable for the preclinical pharmacokinetic
studies on PK13. 相似文献
17.
1H NMR-based metabolomics approach for exploring urinary metabolome modifications after acute and chronic physical exercise 总被引:1,自引:0,他引:1
C. Enea F. Seguin J. Petitpas-Mulliez N. Boildieu N. Boisseau N. Delpech V. Diaz M. Eugène B. Dugué 《Analytical and bioanalytical chemistry》2010,396(3):1167-1176
Metabolomics is a comprehensive method for metabolite assessment that involves measuring the overall metabolic signature of
biological samples. We used this approach to investigate biochemical changes due to acute and chronic physical exercise. Twenty-two
women using identical oral contraceptives were segregated into an untrained (n = 10) or trained (n = 12) group depending on their physical training background. The subjects performed two exercises in a randomized order:
a prolonged exercise test (75% of their
\mathop V· \textO2 max \mathop V\limits^\cdot {{\text{O}}_{2\,\;\max }} until exhaustion) and a short-term, intensive exercise test (short-term, intensive exercise anaerobic test). Urine specimens
were collected before and 30 min after each test. The samples were analyzed by 1H NMR spectroscopy, and multivariate statistical techniques were utilized to process the data. Distinguishing characteristics
were observed only in the urine profiles of specimens collected before vs. 30 min after the short-term, intensive exercise
test. The metabolites responsible for such changes were creatinine, lactate, pyruvate, alanine, β-hydroxybutyrate, acetate,
and hypoxanthine. In both groups, the excretion of lactate, pyruvate, alanine, β-hydroxybutyrate, and hypoxanthine increased
similarly after the completion of the short-term, intensive exercise test (p < 0.03). However, acetate excretion increased to a lesser extent in trained than in untrained subjects (p < 0.05). In conclusion, metabolomics is a promising tool in order to gain insight into physiological status and to clarify
the changes induced by short-term, intense physical exercise. 相似文献
18.
Noreen R Pineau R Chien CC Cestelli-Guidi M Hwu Y Marcelli A Moenner M Petibois C 《Analytical and bioanalytical chemistry》2011,401(3):795-801
Fourier-transform infrared (FTIR) imaging has been used to investigate brain tumor angiogenesis using a mice solid tumor model
and bare-gold (∅ 25 nm) or BaSO4 (∅ 500 nm) nanoparticles (NP) injected into blood vasculature. FTIR images of 20-μm-thick tissue sections were used for chemical
histology of healthy and tumor areas. Distribution of BaSO4-NP (using the 1,218–1,159 cm−1 spectral interval) revealed clearly all details of blood vasculature with morphological abnormalities of tumor capillaries,
while Au-NP (using the 1,046–1,002 cm−1 spectral interval) revealed also diffusion properties of leaky blood vessels. Diffusion of Au-NP out of vascular space reached
64 ± 29 μm, showing the fenestration of “leaky” tumor blood vessels, which should allow small NP (<100 nm, as for Au-NP) to
diffuse almost freely, while large NP should not (as for BaSO4-NP in this study). Therefore, we propose to develop FTIR imaging as a convenient tool for functional molecular histology
imaging of brain tumor vasculature, both for identifying blood capillaries and for determining the extravascular diffusion
space offered by vessel fenestration. 相似文献
19.
A new adsorbent is proposed for the solid-phase extraction of phenol and 1-naphthol from polluted water. The adsorbent (TX-SiO2) is an organosilica composite made from a bifunctional immobilized layer comprising a major fraction (91%) of hydrophilic
diol groups and minor fraction (9%) of the amphiphilic long-chain nonionic surfactant Triton X-100 (polyoxyethylated isooctylphenol)
(TX). Under static conditions phenol was quantitatively extracted onto TX-SiO2 in the form of a 4-nitrophenylazophenolate ion associate with cetyltrimethylammonium bromide. The capacity of TX-SiO2 for phenol is 2.4 mg g−1 with distribution coefficients up to 3.4 × 104 mL g−1; corresponding data for 1-naphthol are 1.5 mg g−1 and 3 × 103 mL g−1. The distribution coefficient does not change significantly for solution volumes of 0.025–0.5 L and adsorbent mass less than
0.03 g; 1–90 μg analyte can be easily eluted by 1–3 mL acetonitrile with an overall recovery of 98.2% and 78.3% for phenol
and 1-naphthol, respectively. Linear correlation between acetonitrile solution absorbance (A
540) and phenol concentration (C) in water was found according to the equation A
540 = (6 ± 1) × 10−2 + (0.9 ± 0.1)C (μmol L−1) with a detection range from 1 × 10−8 mol L−1 (0.9 μL g−1) to 2 × 10−7 mol L−1 (19 μL g−1), a limit of quantification of 1 μL g−1 (preconcentration factor 125), correlation coefficient of 0.936, and relative standard deviation of 2.5%. A solid-phase colorimetric
method was developed for quantitative determination of 1-naphthol on adsorbent phase using scanner technology and RGB numerical
analysis. The detection limit of 1-naphthol with this method is 6 μL g−1 while the quantification limit is 20 μL g−1. A test system was developed for naked eye monitoring of 1-naphthol impurities in water. The proposed test kit allows one
to observe changes in the adsorbent color when 1-naphthol concentration in water is 0.08–3.2 mL g−1. 相似文献
20.
Jaisson S Gorisse L Pietrement C Gillery P 《Analytical and bioanalytical chemistry》2012,402(4):1635-1641
Homocitrulline (HCit), an amino acid formed by the carbamylation of ε-amino groups of lysine residues, is considered a promising
biomarker for monitoring diseases such as chronic renal failure and atherosclerosis. This paper describes a tandem mass spectrometric
method for total, protein-bound and free HCit measurement in plasma samples. HCit was separated from other plasma components
by hydrophilic interaction liquid chromatography. Detection was achieved by monitoring transitions of 190.1 > 127.1 and 190.1 > 173.1
for HCit, and 183.1 > 120.2 for d7-citrulline used as internal standard. This method allowed HCit quantification within 5.2 min and was precise (inter-assay
CV < 5.85%), accurate (mean recoveries ranging from 97% to 106%), and exhibited a good linearity from 10 nmol/L to 1.6 μmol/L.
Plasma samples from control and uremic mice (n = 10) were analyzed. In control mice, mean total plasma HCit concentration was 0.78 ± 0.12 μmol/mol amino acids, whereas
it was increased 2.7-fold in uremic mice plasma, reaching 2.10 ± 0.50 μmol/mol amino acids (p < 0.001). In conclusion, this method exhibits good analytical performances and meets the criteria of sensitivity suitable
for HCit concentration assessment in plasma samples. 相似文献