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1.
The standardisation of a direct radioimmunoassay for progesterone using an125I labeled progesterone prepared by iodinating the tyrosine methyl ester (TME) conjugated to a progesterone hemiphthalate derivative
and an antibody prepared using progesterone linked to bovine serum albumin through 11α hemisuccinate derivative is described.
The hemiphthalate derivative of progesterone was prepared by reacting 11α-hydroxy progesterone with phthalic anhydride which
was then conjugated to TME by using isobutyl chloroformate. The conjugate was iodinated with125I using chloramine-T as oxidising agent and purified by thin layer chromatography. Radiochemical purity of the tracer was
>95% in all batches. The tracer gave 70–75% binding with excess antibody. Assays were optimised with 8-anilino-1-naphthalene
sulphonic acid (ANS) and sodium salicylate as blocking agents to release the progesterone from binding proteins. The assay
optimised with sodium salicylate as blocking agent has a sensitivity of 0.25 ng/ml and a working range of 0.25–50 ng/ml, whereas
the assay with ANS has a sensitivity of 0.75 ng/ml and a working range of 0.75–100 ng/ml. Serum samples were analysed and
compared with the values obtained with a homologous bridge assay. 相似文献
2.
Summary Direct chiral-phase HPLC methods have been developed for the determination of flurbiprofen and its major metabolites, namely
4′-hydroxyflurbiprofen and 3′-hydroxy-4′-methoxyflurbiprofen, in biological fluids using a derivatized amylose chiral stationary
phase (CSP; Chiral-pak AD). Quantification of all three analytes, both free and conjugated, in urine was carried out following
liquid-liquid extraction using tandem ultraviolet (UV) and fluorescence detection. Determination of flurbiprofen and the 4′-hydroxy-metabolite
in plasma utilized the same CSP but required modification in the mobile phase composition and sole use of fluorescence detection.
The urine assay was linear (r>0.998) between 0.05–10 μg mL−1, 0.1–20 μg mL−1 and 0.01–2 μg mL−1 for the enantiomers of flurbiprofen, 4′-hydroxyflurbiprofen and 3′-hydroxy-4′-methoxyflurbiprofen respectively. The plasma
assay was linear (r>0.997) between 0.1–6 μg mL−1 and 0.01–0.6 μg mL−1 for the enantiomers of flurbiprofen and 4′-hydroxyflurbiprofen respectively. Both assays, typically yielded within- and between-day
imprecision and accuracy values less than 10% for the enantiomers of the different analytes. Initial volunteer studies suggest
that the disposition of flurbiprofen displays modest enantioselectivity in humans. 相似文献
3.
Kibum Kim Haehum Jung Hyi-Yoel Yun Seung-Ok Moon Young-Ran Yoon Kwang-il Kwon Hyesoo Kim Soojung Shon Wonku Kang 《Chromatographia》2007,66(3-4):257-260
The purpose of this investigation was to develop a method for measuring the concentration of octylonium in human plasma. Hydrochloric
acid was added to the plasma samples before pretreatment to improve the stability of the octylonium. After liquid–liquid extraction
with ethylacetate and isopropanol (10:1), the analytes were separated by chromatography on a reversed-phase C18 column and detected by LC–MS–MS with electrospray ionization–ionization. The coefficient of variation for the precision of
the assay was less than 10.1%, and the accuracy ranged from 98.0 to 106.5%. The limit of quantification or sensitivity was
0.2 ng mL−1. This method was validated by measuring octylonium in the plasma of healthy human subjects after administration of a single
120-mg oral dose of octylonium bromide. Thus, a highly sensitive and accurate analytical method was developed to determine
the concentration of octylonium in human plasma. 相似文献
4.
Vijaya D. Bharathi Kanbarpa Radharani Banda Jagadeesh Gajjela Ramulu Indu Bhushan Andra Naidu Ramesh Mullangi 《Chromatographia》2008,67(5-6):461-466
A rapid, sensitive, and simple HPLC–MS–MS method, with electro-spray ionization and cetirizine as internal standard (IS),
has been developed and validated for simultaneous quantification of fexofenadine and pseudoephedrine in human plasma. The
analytes were isolated from plasma by solid-phase extraction (SPE) on Oasis HLB cartridges. The compounds were chromatographed
on an RP 18 column with a mixture of ammonium acetate (10 mm, pH 6.4) and methanol as mobile phase. Quantification of the analytes was based on multiple reaction monitoring (MRM) of
precursor-to-product ion pairs m/z 502 → 466 for fexofenadine, m/z 166 → 148 for pseudoephedrine, and m/z 389 → 201 for cetirizine. The linear calibration range for both analytes was 2–1,700 ng mL−1 (r = 0.995), based on analysis of 0.1 mL plasma. Extraction recovery was 91.5 and 80.88% for fexofenadine and pseudoephedrine,
respectively. The method was suitable for analysis of human plasma samples obtained 72 h after administration of a drug containing
both fexofenadine and pseudoephedrine. 相似文献
5.
Validated HPLC–MS–MS method for simultaneous determination of atorvastatin and 2-hydroxyatorvastatin in human plasma—pharmacokinetic study 总被引:1,自引:0,他引:1
Borek-Dohalský V Huclová J Barrett B Nemec B Ulc I Jelínek I 《Analytical and bioanalytical chemistry》2006,386(2):275-285
Cholesterol-reducing statin drugs are the most frequently prescribed agents for reducing morbidity and mortality related to
coronary heart disease. In this publication a validated, highly sensitive, and selective isocratic HPLC method is reported
for quantitative determination of the major statin drug atorvastatin (ATV) and its metabolite 2-hydroxyatorvastatin (HATV).
Detection was performed with an electrospray ionization triple-quadrupole mass spectrometer equipped with an ESI interface
operating in positive-ionization mode. Multiple reaction monitoring (MRM) was used for MS–MS detection. The calibration plot
was linear in the concentration range 0.10–40.00 ng mL−1 for both ATV and HATV. Inter-day and intra-day precision and accuracy of the proposed method were characterized by measurement
of relative standard deviation (RSD) and percentage deviation, respectively; both were less than 8% for both analytes. The
limit of quantitation was 0.02 ng mL−1 for ATV and 0.07 ng mL−1 for HATV. The method was used for pharmacokinetic study of ATV and HATV. Pharmacokinetic data for all analytes are also reported. 相似文献
6.
Zhao J Han X Zhao X Wang C Li Q Chen X Bi K 《Analytical and bioanalytical chemistry》2011,401(1):289-296
A liquid chromatographic–mass spectrometric (LC–MS) method has been developed and validated for simultaneous determination
of dehydroevodiamine and limonin from Evodia rutaecarpa in rat plasma. After addition of the internal standard, domperidone, plasma samples were extracted by liquid–liquid extraction
with ethyl acetate and separated on an Apollo C18 column (250 mm × 4.6 mm, 5 μm), with methanol–0.01% formic acid water (60:40, v/v) as mobile phase, within a runtime of 12.0 min. The analytes were detected without interference in the selected ion monitoring
(SIM) mode with positive electrospray ionization. The linear range was 1.0–500 ng mL−1 for dehydroevodiamine and 2.0–1,000 ng mL−1 for limonin, with lower limits of quantitation of 1.0 and 2.0 ng mL−1, respectively. Intra-day and inter-day precision were within 6.0% and 10.9%, respectively, for both analytes, and the accuracy
(relative error, RE, %) was less than 4.8% and 6.5%, respectively. The validated method was successfully applied to a comparative
pharmacokinetic study of dehydroevodiamine and limonin in rat plasma after oral administration of dehydroevodiamine, limonin,
and an aqueous extract of Evodiae fructus. The results indicated there were obvious differences between the pharmacokinetic behavior after oral administration of an
aqueous extract of Evodiae fructus compared with single substances. 相似文献
7.
A simple high-performance liquid chromatographic method was developed for determining five major components of teicoplanin,
designated A2–1, A2–2, A2–3, A2–4 and A2–5, in human plasma. Using piperacillin sodium as internal standard, teicoplanin in
plasma samples was extracted by coextractive cleanup procedure. The extracts were injected into a Nova-Pak C18 column maintained at ambient temperature. The mobile phase consisted of acetonitrile–0.1% trifluoroacetic acid (27:73, pH = 2.2),
at a flow rate of 1.0 mL min−1. The analytes were detected at the UV wavelength of 218 nm. The method was found to be linear over the concentration range
of 2.5–50 mg L−1 for teicoplanin (r = 0.9993 ± 0.0038), which covered the clinically expected trough plasma levels. The percentage error of the analytical method
was below 9%. The intra- and inter-day reproducibility was adequate with coefficients of variation less than 7%. The chromatographic
running time was 11 min. Thus, the method can be effectively applied to measure teicoplanin concentrations in clinical samples. 相似文献
8.
A method for the simultaneous determination of N-methyl-2-pyrrolidone (NMP) and its metabolites 5-hydroxyl-N-pyrrolidone (5HNMP), N-methylsuccinimide (MSI) and 2-hydroxy-N-methylsuccinimide (2HMSI) in plasma and urine has been developed. Samples were purified by SPE using an ASPEC XL4. Analysis
was performed using LC–MS equipped with an APCI interface. The analysis provided linear responses in the range of 0.125–12 μg
mL−1 for all of the analytes and up to 150 μg mL−1 for 5HNMP and 2HMSI. The within day precision was in the range of 0.9–19.1% for plasma samples and 1.9–10.4% for urine samples
whereas the between day precisions were 4.5–11.9% and 1.2–17.5%, respectively. The method was deemed to be suitable for monitoring
the levels of NMP and its metabolites in the plasma and urine of occupationally exposed persons. 相似文献
9.
A simple and sensitive assay was developed and validated for the simultaneous quantification of rosuvastatin acid (RST), rosuvastatin-5S-lactone (RST-LAC), and N-desmethyl rosuvastatin (DM-RST), in buffered human plasma using liquid chromatography–tandem mass spectrometry (LC-MS/MS).
All the three analytes and the corresponding deuterium-labeled (d6) internal standards were extracted from 50 μL of buffered
human plasma by protein precipitation. The analytes were chromatographically separated using a Zorbax-SB Phenyl column (2.1 mm × 100 mm,
3.5 μm). The mobile phase comprised of a gradient mixture of 0.1% v/v glacial acetic acid in 10% v/v methanol in water (solvent A) and 40% v/v methanol in acetonitrile (solvent B). The analytes were separated at baseline within 6.0 min using a flow rate of 0.35 mL/min.
Mass spectrometry detection was carried out in positive electrospray ionization mode. The calibration curves for all three
analytes were linear (R ≥ 0.9964, n = 3) over the concentration range of 0.1–100 ng/mL for RST and RST-LAC, and 0.5–100 ng/mL for DM-RST. Mean extraction recoveries
ranged within 88.0–106%. Intra- and inter-run mean percent accuracy were within 91.8–111% and percent imprecision was ≤15%.
Stability studies revealed that all the analytes were stable in matrix during bench-top (6 h on ice–water slurry), at the
end of three successive freeze and thaw cycles and at −80°C for 1 month. The method was successfully applied in a clinical
study to determine the concentrations of RST and the lactone metabolite over 12-h post-dose in patients who received a single
dose of rosuvastatin. 相似文献
10.
Clavijo CF Hoffman KL Thomas JJ Carvalho B Chu LF Drover DR Hammer GB Christians U Galinkin JL 《Analytical and bioanalytical chemistry》2011,400(3):715-728
Opioids such as morphine are the cornerstone of pain treatment. The challenge of measuring the concentrations of morphine
and its active metabolites in order to assess human pharmacokinetics and monitor therapeutic drugs in children requires assays
with high sensitivity in small blood volumes. We developed and validated a semi-automated LC-MS/MS assay for the simultaneous
quantification of morphine and its active metabolites morphine 3β-glucuronide (M3G) and morphine 6β-glucuronide (M6G) in human
plasma and in dried blood spots (DBS). Reconstitution in water (DBS only) and addition of a protein precipitation solution
containing the internal standards were the only manual steps. Morphine and its metabolites were separated on a Kinetex 2.6-μm
PFP analytical column using an acetonitrile/0.1% formic acid gradient. The analytes were detected in the positive multiple
reaction mode. In plasma, the assay had the following performance characteristics: range of reliable response of 0.25–1000 ng/mL
(r
2 > 0.99) for morphine, 1–1,000 ng/mL (r
2 > 0.99) for M3G, and 2.5–1,000 ng/mL for M6G. In DBS, the assay had a range of reliable response of 1–1,000 ng/mL (r
2 > 0.99) for morphine and M3G, and of 2.5–1,000 ng/mL for M6G. For inter-day accuracy and precision for morphine, M3G and
M6G were within 15% of the nominal values in both plasma and DBS. There was no carryover, ion suppression, or matrix interferences.
The assay fulfilled all predefined acceptance criteria, and its sensitivity using DBS samples was adequate for the measurement
of pediatric pharmacokinetic samples using a small blood of only 20–50 μL. 相似文献
11.
Summary Elevated plasma homocysteine is, a known risk factor in arteriosclerotic vascular disease. To measure homocysteine in a large
number of samples, we have developed a rapid, simple, robust and inexpensive reversed-phase HPLC method for routine analysis.
Mercaptopro-pionylglycine was used as the internal standard and an external calibration in plasma was performed. Improvement
was achieved by the use of gradient elution (using a sodium acetate buffer and methanol) resulting in a higher number of samples
analyzed per day. Plasma samples were reduced with tributylphosphine and the proteins were precipitated with perchloric acid
before addition of internal standard. The analytes were derivatized by use of 7-fluorobenzofurazone-4-sulfonic acid ammonium
salt. For calibration human plasma was spiked with nine different concentrations of homocysteine (range 2–50 μmol L−1). The inter-assay precision of replicate (n=29) analysis of the concentration of homocysteine in a sample of pooled plasma was 3.0%. The limit of detection, defined
as three times the signal-to-noise ratio, was 0.25 μmol L−1. The linearity of the assay was confirmed for a plasma concentration range of 2–2000 μmol L−1. The variation of duplicate analyses of 842 plasma samples was 2.6±1.7%. 相似文献
12.
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
13.
Garg P Pardasani D Mazumder A Purohit A Dubey DK 《Analytical and bioanalytical chemistry》2011,399(2):955-963
The combination of dispersive solid-phase extraction (DSPE) and Fourier-transform infrared (FTIR) spectroscopy is presented
for detection and quantification of markers and simulants of nerve agents. Hydrophilic–lipophilic balance (HLB) sorbent was
used for extraction and enrichment of organophosphonates from water. When the extraction efficiency of DSPE was compared with
that of conventional solid-phase extraction (SPE), DSPE was more efficient. Extraction conditions such as extraction time,
and type and quantity of sorbent material were optimized. In DSPE, extracted analytes are detected and quantified on the sorbent
using FTIR as analytical technique. Absorbance in FTIR due to P–O–C stretching was used for detection and quantification.
Infrared absorbance of different analytes were compared by determining their molar absorptivities (ε
max). Quantitative analyses were performed employing modified Beer’s law, and relative standard deviations (RSDs) for intraday
repeatability and interday reproducibility were found to be in the range 0.30–0.90% and 0.10–0.80% respectively. The limit
of detection (LOD) was 5–10 μg mL−1. The applicability of the method was tested with an unknown sample prepared by mimicking the sample obtained in an international
official proficiency test. 相似文献
14.
Macwan JS Ionita IA Dostalek M Akhlaghi F 《Analytical and bioanalytical chemistry》2011,400(2):423-433
The aim of the proposed work was to develop and validate a simple and sensitive assay for the analysis of atorvastatin (ATV)
acid, ortho- and para-hydroxy-ATV, ATV lactone, and ortho- and para-hydroxy-ATV lactone in human plasma using liquid chromatography-tandem mass spectrometry. All six analytes and corresponding
deuterium (d5)-labeled internal standards were extracted from 50 μL of human plasma by protein precipitation. The chromatographic
separation of analytes was achieved using a Zorbax-SB Phenyl column (2.1 mm × 100 mm, 3.5 μm). The mobile phase consisted
of a gradient mixture of 0.1% v/v glacial acetic acid in 10% v/v methanol in water (solvent A) and 40% v/v methanol in acetonitrile (solvent B). All analytes including ortho- and para-hydroxy metabolites were baseline-separated within 7.0 min using a flow rate of 0.35 mL/min. Mass spectrometry detection was
carried out in positive electrospray ionization mode, with multiple-reaction monitoring scan. The calibration curves for all
analytes were linear (R
2 ≥ 0.9975, n = 3) over the concentration range of 0.05–100 ng/mL and with lower limit of quantitation of 0.05 ng/mL. Mean extraction recoveries
ranged between 88.6–111%. Intra- and inter-run mean percent accuracy were between 85–115% and percent imprecision was ≤ 15%.
Stability studies revealed that ATV acid and lactone forms were stable in plasma during bench top (6 h on ice-water slurry),
at the end of three successive freeze and thaw cycles and at −80 °C for 3 months. The method was successfully applied in a
clinical study to determine concentrations of ATV and its metabolites over 12 h post-dose in patients receiving atorvastatin. 相似文献
15.
Burhenne J Halama B Maurer M Riedel KD Hohmann N Mikus G Haefeli WE 《Analytical and bioanalytical chemistry》2012,402(7):2439-2450
The benzodiazepine midazolam is a probe drug used to phenotype cytochrome P450 3A activity. In this situation, effective sedative
concentrations are neither needed nor desired, and in fact the use of very low doses is advantageous. We therefore developed
and validated an assay for the femtomolar quantification of midazolam and 1′-hydroxymidazolam in human plasma. Plasma (0.25 mL)
and 96-well-based solid-phase extraction were used for sample preparation. Extraction recoveries ranged between 75 and 92%
for both analytes. Extracts were chromatographed within 2 min on a Waters BEH C18 1.7 μm UPLC? column with a fast gradient
consisting of formic acid, ammonia, and acetonitrile. Midazolam and 1′-hydroxymidazolam were quantified using deuterium- and
13C-labeled internal standards and positive electrospray tandem mass spectrometry in the multiple reaction monitoring mode,
which yielded lower limits of quantification of 50 fg/mL (154 fmol/L) and 250 fg/mL (733 fmol/L) and a corresponding precision
of <20%. The calibrated concentration ranges were linear for midazolam (0.05–250 pg/mL) and 1′-hydroxymidazolam (0.25–125 pg/mL),
with correlation coefficients of >0.99. Within-batch and batch-to-batch precision in the calibrated ranges for both analytes
were <14% and <12%. No ion suppression was detectable, and plasma matrix effects were minimized to <15% (<25%) for midazolam
(1′-hydroxymidazolam). The assay was successfully applied to assess the kinetics of midazolam in two human volunteers after
the administration of single oral microgram doses (1–100 μg). This ultrasensitive assay allowed us to quantify the kinetics
of midazolam and 1′-hydroxymidazolam for at least 10 h, even after the administration of only 1 μg of midazolam. 相似文献
16.
A rapid and simple high performance liquid chromatographic method coupled with tandem mass spectrometry (LC–MS–MS) via electrospray
ionization (ESI) has been developed and validated to separate and simultaneously quantify sodium ferulate (SF), salicylic
acid (SA), cinnarizine (CIN) and vitamin B1 (VB1) in human plasma. Gemfibrozil (GEM) was used as the internal standard (IS)
for SF and SA, whereas lomerizine (LOM) was used as the IS for CIN and VB1. The plasma samples were prepared by one-step protein
precipitation followed by an isocratic elution with 10 mM ammonium acetate buffer (pH = 5.0): acetonitrile (35:65, v/v,) on an Agilent Zorbax SB-CN column (150 mm × 2.0 mm ID, 5 μm). The precursor and product ions of these drugs were monitored
on a triple quadrupole mass spectrometer, operating in the selected reaction monitoring mode (SRM) with polarity switch, in
the negative-ion mode for SF, SA and GEM, in the positive-ion mode for CIN, VB1 and LOM. The method was validated over the
concentration range of 1.5–1,000 ng mL−1 for SF, 20–5,000 ng mL−1 for SA, 2–500 ng mL−1 for CIN, 1–30 ng mL−1 for VB1. The intra- and inter-batch precisions were less than 15% of the relative standard deviation. The recoveries for
analytes and IS achieved from spiked plasma samples were consistent and reproducible. The validated LC–MS–MS method has been
successfully applied to the pharmacokinetic study of sodium ferulate and aspirin capsule in healthy volunteers. 相似文献
17.
The efficiencies of three derivatisation reagents that react with either the amine (9-fluorenylmethyl chloroformate (FMOC)) or the carboxylic acid group (butanol) of amino acid or with both types of functional groups (propyl chloroformate) were compared in the analysis of amino acids by liquid chromatography-electrospray-tandem mass spectrometry (LC-ESI-MS/MS). Separation of 20 amino acids derivatised with these three reagents was studied on reversed-phase chromatography. Linearity, repeatability and limits of detection of the LC-ESI-MS/MS method were determined by analysing FMOC-, butanol- and propyl chloroformate-derivatised lysine, β-aminobutyric acid, threonine and glutamic acid. The limits of detection for the derivatised amino acids (7.5-75 fmol) were as much as 2-60 times lower than those of the corresponding underivatised molecules. The best linearity was observed for amino acids derivatised with propyl chloroformate or butanol (r2 = 0.996-0.999, range = 100-8500 nmol L−1). Propyl chloroformate was the best suited of the reagents tested for the analysis of amino acids with LC-MS/MS and was used for the analysis of amino acids in rat brain microdialysis samples. 相似文献
18.
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
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《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
19.
Moriarty M Lee A O'Connell B Kelleher A Keeley H Furey A 《Analytical and bioanalytical chemistry》2011,401(8):2481-2493
Serotonin is a major neurotransmitter and affects various functions both in the brain and in the rest of the body. It has
been demonstrated that altered serotinergic function is implicated in various psychiatric disorders including depression and
schizophrenia. Serotonin has also been implicated along with dopamine in attention deficit–hyperkinetic disorder (AD-HKD).
This study provides a versatile validated method for the analysis of serotonin, hydroxyindole acetic acid and dopamine in
urine using LC-MS/MS. This method was then used to quantify these analytes in a test group of 17 children diagnosed with severe
AD-HKD. This group was compared to a matched control group to investigate the possibility that one of these compounds may
be a potential biomarker for this condition. The developed method provided good linear calibration curves for the multiplex
assay of analytes in urine (0.05–3.27 nmol/L; R
2 ≥ 0.9977). Acceptable inter-day repeatability was achieved for all analytes with RSD values (n = 9) ranging from 1.1% to 9.3% over a concentration range of 0.11–3.27 μmol/L in urine. Excellent limits of detection (LOD)
and limits of quantitation (LOQ) were achieved with LODs of 8.8–18.2 nmol/L and the LOQs of 29.4–55.7 nmol/L for analytes
in urine. Recoveries were in the ranges of 98–104%, 100–106% and 91–107% for serotonin, 5-HIAA and dopamine, respectively.
An appropriate sample clean-up procedure for urine was developed to ensure efficient recovery and reproducibility on analysis.
Evaluation of matrix effects was also carried out and the influence of ion suppression on analytical results reported. Confirmatory
analysis was carried out on a linear trap quadrupole-Orbitrap mass spectrometer to obtain high mass accuracy data of the target
analytes in the clinical samples. 相似文献
20.
Ben Khelil M Tegethoff M Meinlschmidt G Jamey C Ludes B Raul JS 《Analytical and bioanalytical chemistry》2011,401(4):1153-1162
Steroid hormone concentrations are mostly determined by using different body fluids as matrices and applying immunoassay techniques.
However, usability of these approaches may be restricted for several reasons, including ethical barriers to invasive sampling.
Therefore, we developed an ultra-performance LC–MS–MS method for high-throughput determination of concentrations of cortisol,
cortisone, dehydroepiandrosterone (DHEA), and DHEA sulfate (DHEAS) in small quantities of human nails. The method was validated
for linearity, limits of detection and quantification, recovery, intra and interassay precision, accuracy, and matrix effect.
Samples from 10 adult women were analyzed to provide proof-of-principle for the method’s applicability. Calibration curves
were linear (r
2 > 0.999) in the ranges 10–5000 pg mg−1 for cortisol, cortisone, and DHEAS, and 50–5000 pg mg−1 for DHEA. Limits of quantification were 10 pg mg−1 for cortisol, cortisone, and DHEAS, and 50 pg mg−1 for DHEA. The sensitivity and specificity of the method were good, and there was no interference with the analytes. Mean
recovery of cortisol, cortisone, DHEA, and DHEAS was 90.5%, 94.1%, 84.9%, and 95.9%, respectively, with good precision (coefficient
of variation <14% for all analytes) and accuracy (relative error (%) −8.3% to 12.2% for all analytes). The median (pg mg−1, range) hormone concentrations were 69.5 (36–158), 65 (32–133), 212 (50–1077), and 246 (115–547) for cortisol, cortisone,
DHEA, and DHEAS, respectively. This method enables measurement of cortisol, cortisone, DHEA, and DHEAS in small quantities
of human nails, leading to the development of applications in endocrinology and beyond. 相似文献