Browse
Submit Data
Databases
API
Help

Dataset Information

0 Views

0 Connections

0 Citations

0 Reanalyses

0 Downloads

Omics score: 0

Validation of a liquid chromatography-tandem mass spectrometry method to enable quantification of 3-iodothyronamine from serum.

ABSTRACT: There is great interest lately in the availability of analytical methods for quantification of 3-iodothyronamine from blood and tissues. To date, no validated method for determination of 3-iodothyronamine from biological matrices has been described. Detailed in this report is an LC-MS/MS method that permits accurate and reproducible quantification of pharmacological concentrations of 3-iodothyronamine from rat serum, with a 0.0008 M lower limit of quantification. Endogenous 3-iodothyronamine was observed from rodent and human serum (0.2 mL) at the method limit of detection. In summary, the LC-MS/MS method enables quantification of circulating 3-iodothyronamine to allow examination of a relationship with biological activity.

SUBMITTER: DeBarber AE

PROVIDER: S-EPMC3609708 | biostudies-literature | 2008 Nov

REPOSITORIES: biostudies-literature

ACCESS DATA

Json Xml

Publications

Validation of a liquid chromatography-tandem mass spectrometry method to enable quantification of 3-iodothyronamine from serum.

DeBarber Andrea E AE Geraci Travis T Colasurdo Vincent P VP Hackenmueller Sarah A SA Scanlan Thomas S TS

Journal of chromatography. A 20080912 1

There is great interest lately in the availability of analytical methods for quantification of 3-iodothyronamine from blood and tissues. To date, no validated method for determination of 3-iodothyronamine from biological matrices has been described. Detailed in this report is an LC-MS/MS method that permits accurate and reproducible quantification of pharmacological concentrations of 3-iodothyronamine from rat serum, with a 0.0008 M lower limit of quantification. Endogenous 3-iodothyronamine was ...[more]

PMID: 18823891

Similar Datasets

Identification and quantification of 3-iodothyronamine metabolites in mouse serum using liquid chromatography-tandem mass spectrometry.

Project description:3-Iodothyronamine (T(1)AM) is an endogenous derivative of thyroxine. Recently there have been numerous reports of analytical methods to quantify endogenous T(1)AM levels, but substantial discrepancies in concentration depending on the method of analysis (LC-MS/MS or immunoassay) suggest endogenous T(1)AM may be covalently modified in vivo. Using information dependent acquisition methods to perform unbiased scans for T(1)AM metabolites following a single IP injection in mice, we have identified O-sulfonate-T(1)AM, N-acetyl-T(1)AM and T(1)AM-glucuronide as conjugates occurring in vivo, as well as the oxidatively deaminated 3-iodothyroacetic acid and non-iodinated thyroacetic acid. 3-iodothyroacetic acid, O-sulfonate-T(1)AM and T(1)AM-glucuronide are present in serum at greater concentrations that unmodified T(1)AM and all metabolites are extensively distributed to tissues. These results suggest covalent modifications of T(1)AM may play a critical role in regulating distribution and biological activity of T(1)AM, and analytical methods to quantify endogenous T(1)AM should be able to account for these metabolites as well.

| S-EPMC3609710 | biostudies-literature

Quantification of regional DNA methylation by liquid chromatography/tandem mass spectrometry.

Project description:Promoter hypermethylation-associated tumor suppressor gene (TSG) silencing has been explored as a therapeutic target for hypomethylating agents. Promoter methylation change may serve as a pharmacodynamic endpoint for evaluation of the efficacy of these agents and predict the patient's clinical response. Here a liquid chromatography-tandem mass spectrometry (LC-MS/MS) assay has been developed for quantitative regional DNA methylation analysis using the molar ratio of 5-methyl-2'-deoxycytidine (5mdC) to 2'-deoxycytidine (2dC) in the enzymatic hydrolysate of fully methylated bisulfite-converted polymerase chain reaction (PCR) amplicons as the methylation indicator. The assay can differentiate 5% of promoter methylation level with an intraday precision ranging from 3 to 16% using two TSGs: HIN-1 and RASSF1A. This method was applied to characterize decitabine-induced promoter DNA methylation changes of these two TSGs in a breast cancer MCF-7 cell line. Promoter methylation of these TSGs was found to decrease in a dose-dependent manner. Correspondingly, the expression of these TSGs was enhanced. The sensitivity and reproducibility of the method make it a valuable tool for specific gene methylation analysis that could aid characterization of hypomethylating activity on specific genes by hypomethylating agents in a clinical setting.

| S-EPMC3939067 | biostudies-literature

Liquid Chromatography Tandem Mass Spectrometry Quantification of 13C-Labeling in Sugars.

Project description:Subcellular compartmentation has been challenging in plant 13C-metabolic flux analysis. Indeed, plant cells are highly compartmented: they contain vacuoles and plastids in addition to the regular organelles found in other eukaryotes. The distinction of reactions between compartments is possible when metabolites are synthesized in a particular compartment or by a unique pathway. Sucrose is an example of such a metabolite: it is specifically produced in the cytosol from glucose 6-phosphate (G6P) and fructose 6-phosphate (F6P). Therefore, determining the 13C-labeling in the fructosyl and glucosyl moieties of sucrose directly informs about the labeling of cytosolic F6P and G6P, respectively. To date, the most commonly used method to monitor sucrose labeling is by nuclear magnetic resonance, which requires substantial amounts of biological sample. This study describes a new methodology that accurately measures the labeling in free sugars using liquid chromatography tandem mass spectrometry (LC-MS/MS). For this purpose, maize embryos were pulsed with [U-13C]-fructose, intracellular sugars were extracted, and their time-course labeling was analyzed by LC-MS/MS. Additionally, extracts were enzymatically treated with hexokinase to remove the soluble hexoses, and then invertase to cleave sucrose into fructose and glucose. Finally, the labeling in the glucosyl and fructosyl moieties of sucrose was determined by LC-MS/MS.

| S-EPMC7022953 | biostudies-literature

Isobaric protein-level labeling strategy for serum glycoprotein quantification analysis by liquid chromatography-tandem mass spectrometry.

Project description:While peptide-level labeling using isobaric tag reagents has been widely applied for quantitative proteomics experiments, there are comparatively few reports of protein-level labeling. Intact protein labeling could be broadly applied to quantification experiments utilizing protein-level separations or enrichment schemes. Here, protein-level isobaric labeling was explored as an alternative strategy to peptide-level labeling for serum glycoprotein quantification. Labeling and digestion conditions were optimized by comparing different organic solvents and enzymes. Digestions with Asp-N and trypsin were found highly complementary; combining the results enabled quantification of 30% more proteins than either enzyme alone. Three commercial reagents were compared for protein-level labeling. Protein identification rates were highest with iTRAQ 4-plex when compared to TMT 6-plex and iTRAQ 8-plex using higher-energy collisional dissociation on an Orbitrap Elite mass spectrometer. The compatibility of isobaric protein-level labeling with lectin-based glycoprotein enrichment was also investigated. More than 74% of lectin-bound labeled proteins were known glycoproteins, which was similar to results from unlabeled and peptide-level labeled serum samples. Finally, protein-level and peptide-level labeling strategies were compared for serum glycoprotein quantification. Isobaric protein-level labeling gave comparable identification levels and quantitative precision to peptide-level labeling.

| S-EPMC3690282 | biostudies-literature

Quantification of glycopeptides by multiple reaction monitoring liquid chromatography/tandem mass spectrometry.

Project description:Protein glycosylation has a major influence on functions of proteins. Studies have shown that aberrations in glycosylation are indicative of disease conditions. This has prompted major research activities for comparative studies of glycoproteins in biological samples. Multiple reaction monitoring (MRM) is a highly sensitive technique which has been recently explored for quantitative proteomics. In this work, MRM was adopted for quantification of glycopeptides derived from both model glycoproteins and depleted human blood serum using glycan oxonium ions as transitions. The utilization of oxonium ions aids in identifying the different types of glycans bound to peptide backbones. MRM experiments were optimized by evaluating different parameters that have a major influence on quantification of glycopeptides, which include MRM time segments, number of transitions, and normalized collision energies. The results indicate that oxonium ions could be adopted for the characterization and quantification of glycopeptides in general, eliminating the need to select specific transitions for individual precursor ions. Also, the specificity increased with the number of transitions and a more sensitive analysis can be obtained by providing specific time segments. This approach can be applied to comparative and quantitative studies of glycopeptides in biological samples as illustrated for the case of depleted blood serum sample.

| S-EPMC3673029 | biostudies-literature

Assay reproducibility of serum androgen measurements using liquid chromatography-tandem mass spectrometry.

Project description:BACKGROUND:Valid and precise measures of androgen concentrations are needed for etiologic studies of hormonally-related cancers. We developed a high-performance liquid chromatography-tandem mass spectrometry (LC-MS/MS) method with two sample preparations to measure 11 androgens, including adrenal and gonadal androgenic precursors and their 5?-reduced metabolites. METHODS:Androgen levels were measured in serum from 20 healthy volunteers (5 men, 10 premenopausal women, 5 postmenopausal women). Two blinded, randomized aliquots per individual were assayed in each of three batches. A fourth batch of samples was measured at an external laboratory using comparable methodology to measure 9 of the 11 androgens. Coefficients of variation (CV) and intraclass correlation coefficients (ICC) were calculated from the individual components of variance. Comparability of 9 androgens across laboratories was assessed using Spearman ranked correlations, Deming regression and bias plots. RESULTS:The laboratory CVs were <5% and ICCs were uniformly high (>95%) for all androgens measured across sex/menopausal status groups. Spearman ranked correlations for 9 hormones measured in the comparison laboratory were high (>0.85), suggesting good agreement. CONCLUSION:Our high-performance LC-MS/MS assays of 11 androgens, including adrenal and gonadal androgenic precursors and their 5?-reduced metabolites demonstrated excellent laboratory reproducibility, and good comparability with an established method that measured 9 of the 11 hormones tested. The serum androgen metabolite assays are suitable for use in epidemiologic research.

| S-EPMC4663146 | biostudies-literature

Determination of bedaquiline in human serum using liquid chromatography-tandem mass spectrometry.

Project description:Bedaquiline, a diarylquinoline for the treatment of multidrug-resistant tuberculosis (TB), relies on exposure-dependent killing. As data on drug exposure in specific populations are scarce, pharmacokinetic studies may be of interest. No simple and robust validated liquid chromatography-tandem mass spectrometry (LC-MS/MS) method has been reported to date. Therefore, a new method using a quadrupole mass spectrometer was developed for analysis of bedaquiline and N-monodesmethyl bedaquiline (M2) in human serum, using deuterated bedaquiline as the internal standard. The calibration curve was linear over a range of 0.05 (lower limit of quantification [LLOQ]) to 6.00 mg/liter for both bedaquiline and M2, with correlation coefficient values of 0.997 and 0.999, respectively. The calculated accuracy ranged from 1.9% to 13.6% for bedaquiline and 2.9% to 8.5% for M2. Within-run precision ranged from 3.0% to 7.2% for bedaquiline and 3.1% to 5.2% for M2, and between-run precision ranged from 0.0% to 4.3% for bedaquiline and 0.0% to 4.6% for M2. Evaluation of serum concentrations in a patient receiving bedaquiline showed high levels at the end of treatment, reflecting accumulation of the drug. More observational pharmacokinetic data are needed to relate altered drug concentrations to clinical outcome or adverse drug effects. A simple LC-MS/MS method to quantify bedaquiline and M2 levels in human serum using a deuterated internal standard has been validated. This method can be used in clinical studies and daily practice.

| S-EPMC4538542 | biostudies-literature

Simultaneous phenotyping and quantification of ?-1-antitrypsin by liquid chromatography-tandem mass spectrometry.

Project description:BACKGROUND:?-1-Antitrypsin (A1AT) deficiency results from a genetic disorder at 2 common loci. Diagnosis requires quantification of A1AT and subsequent identification of the specific variant. The current algorithm of laboratory testing for the diagnosis of A1AT deficiency uses a combination of quantification (nephelometry), genotyping, and/or phenotyping. We developed a multiple reaction monitoring liquid chromatography-tandem mass spectrometry (LC-MS/MS) method for simultaneous quantification of A1AT and identification of the 2 most common deficiency alleles present in 95% of the patients with A1AT deficiency. METHODS:Serum samples (n = 40) were digested with trypsin, and appropriate ¹³C/¹?N-labeled standard peptides were added. We performed LC-MS/MS analysis with a 0.5- by 150-mm C18 column and H?O:acetonitrile:n-propanol:formic acid (A:98:1:1:0.2 and B:10:80:10:0.2; flow 12 ?L/min) mobile phase in positive ion mode on a TSQ Quantum triple quadrupole MS system. We measured the A1AT concentration by comparison to a calibration curve and determined the phenotype by the presence or absence of variant peptides. We compared the results to the current phenotyping assay by isoelectric focusing (IEF) and the immunonephelometry quantitative assay. RESULTS:For A1AT allele detection, in 39 of 40 samples the LC-MS/MS results were identical to those obtained by IEF gel electrophoresis. The single discrepant result was rerun by IEF at a lower dilution, and the results were in concordance. The A1AT quantification by LC-MS/MS also compared favorably with nephelometry. CONCLUSIONS:The LC-MS/MS method correlates well with current phenotyping and nephelometric assays and has the potential to improve the laboratory diagnosis of genetic A1AT deficiency.

| S-EPMC3275912 | biostudies-literature

Simultaneous quantification of multiple urinary naphthalene metabolites by liquid chromatography tandem mass spectrometry.

Project description:Naphthalene is an environmental toxicant to which humans are exposed. Naphthalene causes dose-dependent cytotoxicity to murine airway epithelial cells but a link between exposure and human pulmonary disease has not been established. Naphthalene toxicity in rodents depends on P450 metabolism. Subsequent biotransformation results in urinary elimination of several conjugated metabolites. Glucuronide and sulfate conjugates of naphthols have been used as markers of naphthalene exposure but, as the current studies demonstrate, these assays provide a limited view of the range of metabolites generated from the parent hydrocarbon. Here, we present a liquid chromatography tandem mass spectrometry method for measurement of the glucuronide and sulfate conjugates of 1-naphthol as well as the mercapturic acids and N-acetyl glutathione conjugates from naphthalene epoxide. Standard curves were linear over 2 log orders. On column detection limits varied from 0.91 to 3.4 ng; limits of quantitation from 1.8 to 6.4 ng. The accuracy of measurement of spiked urine standards was -13.1 to + 5.2% of target and intra-day and inter-day variability averaged 7.2 (± 4.5) and 6.8 (± 5.0) %, respectively. Application of the method to urine collected from mice exposed to naphthalene at 15 ppm (4 hrs) showed that glutathione-derived metabolites accounted for 60-70% of the total measured metabolites and sulfate and glucuronide conjugates were eliminated in equal amounts. The method is robust and directly measures several major naphthalene metabolites including those derived from glutathione conjugation of naphthalene epoxide. The assays do not require enzymatic deconjugation, extraction or derivatization thus simplifying sample work up.

| S-EPMC4390350 | biostudies-literature

Quantification of cortisol in human eccrine sweat by liquid chromatography - tandem mass spectrometry.

Project description:Cortisol has long been recognized as the "stress biomarker" in evaluating stress related disorders. Plasma, urine or saliva are the current source for cortisol analysis. The sampling of these biofluids is either invasive or has reliability problems that could lead to inaccurate results. Sweat has drawn increasing attention as a promising source for non-invasive stress analysis. A sensitive HPLC-MS/MS method was developed for the quantitation of cortisol ((11β)-11,17,21-trihydroxypregn-4-ene-3,20-dione) in human eccrine sweat. At least one unknown isomer that has previously not been reported and could potentially interfere with quantification was separated from cortisol with mixed mode RP HPLC. Detection of cortisol was carried out using atmospheric pressure chemical ionization (APCI) and selected reaction monitoring (SRM) in positive ion mode, using cortisol-9,11,12,12-D4 as internal standard. LOD and LOQ were estimated to be 0.04 ng ml(-1) and 0.1 ng ml(-1), respectively. Linear range of 0.10-25.00 ng ml(-1) was obtained. Intraday precision (2.5%-9.7%) and accuracy (0.5%-2.1%), interday precision (12.3%-18.7%) and accuracy (7.1%-15.1%) were achieved. This method has been successfully applied to the cortisol analysis of human eccrine sweat samples. This is the first demonstration that HPLC-MS/MS can be used for the sensitive and highly specific determination of cortisol in human eccrine sweat in the presence of at least one isomer that has similar hydrophobicity as cortisol. This study demonstrated that human eccrine sweat could be used as a promising source for non-invasive assessment of stress biomarkers such as cortisol and other steroid hormones.

| S-EPMC5376102 | biostudies-literature

OmicsDI is part of the ELIXIR infrastructure

OmicsDI is an Elixir interoperability service. Learn more ›

Tweets

OmicsDI Databases

PRIDE
PeptideAtlas
MassIVE
JPOST Repository
Physiome Model Repository

EGA
EVA
ENA
LINCS
PAXDB
Cell Collective

MetaboLights
Metabolomics Workbench
MetabolomeExpress
GNPS
BioModels
FAIRDOMHub

ArrayExpress
dbGaP
ExpressionAtlas
GEO
NODE

Information

Databases
Help
API
Contact us
Code on GitHub
Terms of use
Submit Data