scholarly journals Validated ICP-MS method for measurement of plasma and intracellular antimony concentrations applied to pharmacokinetics of meglumine antimoniate

2020 ◽  
Author(s):  
Diana J. Garay-Baquero ◽  
David E. Rebellon-Sanchez ◽  
Miguel D. Prieto ◽  
Lina Giraldo-Parra ◽  
Adriana Navas ◽  
...  
Keyword(s):  
Human Plasma ◽  
Inductively Coupled Plasma ◽  
Mononuclear Cells ◽  
Internal Standard ◽  
Reference Method ◽  
Clinical Samples ◽  
Peripheral Blood Mononuclear ◽  
Meglumine Antimoniate ◽  
Icp Ms ◽  
Limit Of Quantitation

Aim A high-throughput method using inductively coupled plasma mass spectrometry (ICP-MS) was developed and validated for the quantitative analysis of antimony in human plasma and peripheral blood mononuclear cells (PBMCs) from patients with cutaneous leishmaniasis undergoing treatment with meglumine antimoniate. Methods For this study, antimony was digested in clinical samples with 1% TMAH / 1% EDTA and indium was used as internal standard. Calibration curves for antimony, over the range of 25 to 10000 ng/mL were fitted to a linear model using a weighting of 1/concentration2. Accuracy, precision and stability were evaluated. Results Taking the lower limit of quantitation (LLOQ) to be the lowest validation concentration with precision and accuracy within 20% (25% at the LLOQ), the current assay was successfully validated from 25 to 10000 ng/mL for antimony in human plasma and PBMCs. Dilution studies demonstrated that concentrations up to 100000 ng/mL of antimony in plasma were reliably analyzed when diluted into the calibration range. Conclusion This protocol will serve as a baseline for future analytical designs, aiming to provide a reference method to allow inter-study comparisons.

scholarly journals Inductively coupled plasma mass spectrometry method for plasma and intracellular antimony quantification applied to pharmacokinetics of meglumine antimoniate

Bioanalysis ◽  
2021 ◽  
Author(s):  
Diana J Garay-Baquero ◽  
David E Rebellón-Sánchez ◽  
Miguel D Prieto ◽  
Lina Giraldo-Parra ◽  
Adriana Navas ◽  
...  
Keyword(s):  
Mass Spectrometry ◽  
Human Plasma ◽  
Peripheral Blood Mononuclear Cells ◽  
Peripheral Blood ◽  
Inductively Coupled Plasma ◽  
Mononuclear Cells ◽  
Peripheral Blood Mononuclear ◽  
Inductively Coupled ◽  
Blood Mononuclear Cells ◽  
Plasma Mass Spectrometry

Background: A high-throughput method using inductively coupled plasma mass spectrometry (ICP–MS) was developed and validated for the quantitative analysis of antimony in human plasma and peripheral blood mononuclear cells from patients with cutaneous leishmaniasis undergoing treatment with meglumine antimoniate. Materials & methods: Antimony was digested in clinical samples with 1% tetramethylammonium hydroxide/1% EDTA and indium was used as internal standard. Accuracy, precision and stability were evaluated. Conclusion: Taking the lower limit of quantitation to be the lowest validation concentration with precision and accuracy within 20%, the current assay was successfully validated from 25 to 10000 ng/ml for antimony in human plasma and peripheral blood mononuclear cells. This protocol will serve as a baseline for future analytical designs, aiming to provide a reference method to allow inter-study comparisons.

A candidate reference method for serum potassium measurement by inductively coupled plasma mass spectrometry

2017 ◽  
Vol 55 (10) ◽  
Author(s):  
Ying Yan ◽  
Bingqing Han ◽  
Jie Zeng ◽  
Weiyan Zhou ◽  
Tianjiao Zhang ◽  
...  
Keyword(s):  
Mass Spectrometry ◽  
Serum Potassium ◽  
Inductively Coupled Plasma ◽  
Low Cost ◽  
Internal Standard ◽  
Reference Method ◽  
Serum Samples ◽  
Inductively Coupled ◽  
Icp Ms ◽  
Plasma Mass Spectrometry

AbstractBackground:Potassium is an important serum ion that is frequently assayed in clinical laboratories. Quality assurance requires reference methods; thus, the establishment of a candidate reference method for serum potassium measurements is important.Methods:An inductively coupled plasma mass spectrometry (ICP-MS) method was developed. Serum samples were gravimetrically spiked with an aluminum internal standard, digested with 69% ultrapure nitric acid, and diluted to the required concentration. TheResults:The correlation coefficients between the measuredConclusions:The new ICP-MS method is specific, precise, simple, and low-cost, and it may be used as a candidate reference method for standardizing serum potassium measurements.

A candidate reference method using ICP-MS for sweat chloride quantification

2016 ◽  
Vol 54 (4) ◽  
Author(s):  
Jake T. Collie ◽  
R. John Massie ◽  
Oliver A.H. Jones ◽  
Paul D. Morrison ◽  
Ronda F. Greaves
Keyword(s):  
Inductively Coupled Plasma ◽  
Reference Method ◽  
Accurate Method ◽  
Quality Assurance Program ◽  
Inductively Coupled ◽  
Sweat Chloride ◽  
Icp Ms ◽  
Target Values ◽  
Limit Of Quantitation ◽  
On Line

AbstractThe aim of the study was to develop a method for sweat chloride (Cl) quantification using Inductively Coupled Plasma Mass Spectrometry (ICP-MS) to present to the Joint Committee for Traceability in Laboratory Medicine (JCTLM) as a candidate reference method for the diagnosis of cystic fibrosis (CF).Calibration standards were prepared from sodium chloride (NaCl) to cover the expected range of sweat Cl values. Germanium (Ge) and scandium (Sc) were selected as on-line (instrument based) internal standards (IS) and gallium (Ga) as the off-line (sample based) IS. The method was validated through linearity, accuracy and imprecision studies as well as enrolment into the Royal College of Pathologists of Australasia Quality Assurance Program (RCPAQAP) for sweat electrolyte testing.Two variations of the ICP-MS method were developed, an on-line and off-line IS, and compared. Linearity was determined up to 225 mmol/L with a limit of quantitation of 7.4 mmol/L. The off-line IS demonstrated increased accuracy through the RCPAQAP performance assessment (CV of 1.9%, bias of 1.5 mmol/L) in comparison to the on-line IS (CV of 8.0%, bias of 3.8 mmol/L). Paired t-tests confirmed no significant differences between sample means of the two IS methods (p=0.53) or from each method against the RCPAQAP target values (p=0.08 and p=0.29).Both on and off-line IS methods generated highly reproducible results and excellent linear comparison to the RCPAQAP target results. ICP-MS is a highly accurate method with a low limit of quantitation for sweat Cl analysis and should be recognised as a candidate reference method for the monitoring and diagnosis of CF. Laboratories that currently practice sweat Cl analysis using ICP-MS should include an off-line IS to help negate any pre-analytical errors.

scholarly journals Calcineurin Activity Assay Measurement by Liquid Chromatography–Tandem Mass Spectrometry in the Multiple Reaction Monitoring Mode

2014 ◽  
Vol 60 (2) ◽  
pp. 353-360 ◽  
Author(s):  
Lynn Carr ◽  
Anne-Laure Gagez ◽  
Marie Essig ◽  
François-Ludovic Sauvage ◽  
Pierre Marquet ◽  
...  
Keyword(s):  
Mass Spectrometry ◽  
Liquid Chromatography ◽  
Mononuclear Cells ◽  
Multiple Reaction Monitoring ◽  
Internal Standard ◽  
Reaction Monitoring ◽  
Activity Assay ◽  
Peripheral Blood Mononuclear ◽  
Blood Concentrations ◽  
Transplant Patients

Abstract BACKGROUND Blood concentrations of the calcineurin inhibitors (CNIs) cyclosporine and tacrolimus are currently measured to monitor immunosuppression in transplant patients. The measurement of calcineurin (CN) phosphatase activity has been proposed as a complementary pharmacodynamic approach. However, determining CN activity with current methods is not practical. We developed a new method amenable to routine use. METHODS Using liquid chromatography–multiple reaction monitoring mass spectrometry (LC-MRM-MS), we quantified CN activity by measuring the dephosphorylation of a synthetic phosphopeptide substrate. A stable isotope analog of the product peptide served as internal standard, and a novel inhibitor cocktail minimized dephosphorylation by other major serine/threonine phosphatases. The assay was used to determine CN activity in peripheral blood mononuclear cells (PBMCs) isolated from 20 CNI-treated kidney transplant patients and 9 healthy volunteers. RESULTS Linearity was observed from 0.16 to 2.5 μmol/L of product peptide, with accuracy in the 15% tolerance range. Intraassay and interassay recoveries were 100.6 (9.6) and 100 (7.5), respectively. Michaelis–Menten kinetics for purified CN were Km = 10.7 (1.6) μmol/L, Vmax = 2.8 (0.3) μmol/min · mg, and for Jurkat lysate, Km = 182.2 (118.0) μmol/L, Vmax = 0.013 (0.006) μmol/min · mg. PBMC CN activity was successfully measured in a single tube with an inhibitor cocktail. CONCLUSIONS Because LC-MRM-MS is commonly used in routine clinical dosage of drugs, this CN activity assay could be applied, with parallel blood drug concentration monitoring, to a large panel of patients to reevaluate the validity of PBMC CN activity monitoring.

scholarly journals Quantitation of Intracellular Triphosphate of Emtricitabine in Peripheral Blood Mononuclear Cells from Human Immunodeficiency Virus-Infected Patients

1999 ◽  
Vol 43 (9) ◽  
pp. 2245-2250 ◽  
Author(s):  
Albert Darque ◽  
Gilles Valette ◽  
Frank Rousseau ◽  
Laurene H. Wang ◽  
Jean-Pierre Sommadossi ◽  
...  
Keyword(s):  
Human Immunodeficiency Virus ◽  
Anion Exchange ◽  
Peripheral Blood Mononuclear Cells ◽  
Peripheral Blood ◽  
Mononuclear Cells ◽  
Solid Phase ◽  
Peripheral Blood Mononuclear ◽  
Limit Of Quantitation ◽  
Immunodeficiency Virus ◽  
Blood Mononuclear Cells

ABSTRACT An analytical methodology combining solid-phase extraction (SPE) and high-performance liquid chromatography (HPLC) was developed to quantitate the intracellular active 5′-triphosphate (TP) of β-l-2′,3′-dideoxy-5-fluoro-3′-thiacytidine (emtricitabine) (FTC) in human peripheral blood mononuclear cells (PBMCs). The FTC nucleotides, including 5′-mono-, di-, and triphosphates, were successively resolved on an anion-exchange SPE cartridge by applying a gradient of potassium chloride. The FTC-TP was subsequently digested to release the parent nucleoside that was finally analyzed by HPLC with UV detection (HPLC-UV). Validation of the methodology was performed by using PBMCs from healthy donors exposed to an isotopic solution of [3H]FTC with known specific activity, leading to the formation of intracellular FTC-TP that was quantitated by an anion-exchange HPLC method with radioactive detection. These levels of FTC-TP served as reference values and were used to validate the data obtained by HPLC-UV. The assay had a limit of quantitation of 4.0 pmol of FTC-TP (amount on column from approximately 107 cells). Intra-assay precision (coefficient of variation percentage of repeated measurement) and accuracy (percentage deviation of the nominal reference value), estimated by using quality control samples at 16.2, 60.7, and 121.5 pmol, ranged from 1.3 to 3.3% and −1.0 to 4.8%, respectively. Interassay precision and accuracy varied from 3.0 to 10.2% and from 2.5 to 6.7%, respectively. This methodology was successfully applied to the determination of FTC-TP in PBMCs of patients infected with human immunodeficiency virus after oral administration of various dosing regimens of FTC monotherapy.

scholarly journals DEVELOPMENT AND VALIDATION OF BIOANALYTICAL HPLC METHOD FOR SIMULTANEOUS ESTIMATION OF CILNIDIPINE AND NEBIVOLOL IN HUMAN PLASMA

2017 ◽  
Vol 9 (10) ◽  
pp. 253
Author(s):  
Aruna G. ◽  
Bharathi K ◽  
Kvsrg Prasad
Keyword(s):  
Human Plasma ◽  
Analytical Method ◽  
Internal Standard ◽  
Hplc Method ◽  
Pharmacokinetic Parameters ◽  
Simultaneous Estimation ◽  
Time Data ◽  
Bioanalytical Method Validation ◽  
Limit Of Quantitation ◽  
The Mean

Objective: To develop and validate a modified isocratic reversed-phase high performance liquid chromatographic (RP-HPLC) method for determination of cilnidipine and nebivolol in human plasma to be used for pharmacokinetic studies.Methods: The drug was extracted from plasma samples by direct protein precipitation technique using acetonitrile. Amlodipine was used as internal standard (IS). Samples were analyzed on BDS C18 column (250 x 4.6 mm, 5 µm), applying ortho phosphoric acid (0.1%): Acetonitrile, at a ratio of 45:55 v/v in isocratic mode as a mobile phase at a flow rate of 1 ml/min to attain adequate resolution. Separations were performed at room temperature and monitored at a wavelength of 260 nm after injection of 50μl samples into the HPLC system. The analytical method was validated according to FDA bioanalytical method validation guidance. The method was applied for pharmacokinetic study of cilnidipine and nebivolol tablets-10 mg and 5 mg were administered as a single dose to 6 healthy male rabbits under fasting condition. Twelve blood samples were withdrawn from each rabbit over 24 h periods. From the plasma concentration-time data of each individual, the pharmacokinetic parameters; Cmax, Tmax, AUC0-t and AUC0-∞ were calculated.Results: A peak area was obtained for cilnidipine and nebivolol at 3.943 and 4.719 min retention time respectively. Linearity was established at a concentration range of 0.20-20 μg/ml (r2=0.999, n=8) for cilnidipine and 0.02-2 μg/ml (r2=0.999, n=8) for nebivolol. The lower limit of quantitation (LLOQ) was identifiable and reproducible at 0.2μg/ml for cilnidipine and 0.02 μg/ml for nebivolol. The coefficients of variation (%cv) of the intra-day and inter-day precision of cilnidipine at 600, 1000 and 1600ng/ml levels were found to be 6.90%, 6.19%, 5.22%; and 7.74%, 6.54%, 5.77%, respectively, which are lower than the accepted criteria limits (15-20 %). The mean recovery (%) cilnidipine at 600, 1000, and 1600ng/ml was found to be 101.03%, 99.27% and 104.87%, and for nebivolol 60, 100, and 160 ng/ml was found to be 106.13%, 107.03% and 98.06% respectively. Stability at different conditions and in autosampler was also established. The mean pharmacokinetic parameters; Cmax, Tmax, AUC0-t and AUC0-∞ were 6 ng/ml, 2 hr, 96.76 mg. hr/ml, 63.45 mg. hr/ml for cilnidipine and 5.8ng/ml, 2hr, 74.78 mg. hr/ml, 100.25 mg. hr/ml for nebivolol respectively.Conclusion: The present analytical method was found to be specific, sensitive, accurate and precise for quantification of cilnidipine and nebivolol in human plasma. It can be successively applied for pharmacokinetics, bioavailability and bioequivalence studies.

scholarly journals A sensitive and reliable RP-HPLC method for the detection of cimetidine – a H2 receptor antagonist in human plasma

2019 ◽  
Vol 8 (3) ◽  
pp. 671-674
Keyword(s):  
Human Plasma ◽  
High Performance ◽  
Internal Standard ◽  
Bioequivalence Study ◽  
High Concentration ◽  
H2 Receptor Antagonist ◽  
Chromatography Method ◽  
Thaw Cycle ◽  
Limit Of Quantitation ◽  
The Mean

Bioanalytical methods for bioequivalence studies require high sensibility and rapidity due to the large number of samples and the low plasma concentration of drugs. The present study aimed to develop and validate a high-performance liquid chromatography method to quantify cimetidine (CMT) in human plasma and to apply it in a bioequivalence study. Spiked plasma of 500 µl (l, m and h concentration) was used for the assay. The HPLC injection volume was 20μl of the reconstitute sample where, 2 ml of ethyl acetate used for extraction purposes. Cimetidine was prepared separately for low (80 ng/ml), medium (2000 ng/ml) and high (3600 ng/ml) concentrations and internal standard (ranitidine) concentration was 3000 ng/ml. Freeze thawing and long terms stability were conducted at -25º c. The individual calibration curve for spiked standards was linear with R2= 0.99. The inaccuracy values for QC samples were within 15% of the actual value and not more than 20% for the LOQ. The limit of quantitation (LOQ) was 40 ng/ml, which was also the lowest concentration of cimetidine that was quantitated with the variability of 5.9%. The within day precision and between day precision for LOQ were 10.8 and 5.9 respectively. The retention time for the analyte was 4.1-4.5 minutes during the within a day and between day results. The mean % inaccuracy values for low, medium and high concentration were 6.8, 5.6 and 7.8 respectively for within day and 2.4, 6.1 and 7.9 respectively for between days. The within day and between day % inaccuracy for LOQ concentration was 12.4 and 5.5 respectively. The mean recoveries for low, medium and high concentration of cimetidine were 80.2, 70.9 and 74.2. The overall mean recovery for cimetidine was 75.1%. The maximum inaccuracy for freeze thaw cycle and long term stability samples for low, medium and high was found with CV less than 15% for all concentrations, indicating that cimetidine is stable. The developed method was precise and accurate and was suitable to be applied for the bioequivalence study of cimetidine.

Quantitation of ivosidenib in human plasma via LC–MS/MS and its application in clinical trials

Bioanalysis ◽  
2021 ◽  
Author(s):  
Feng Yin ◽  
Shaoxia Yu ◽  
Rohini Narayanaswamy ◽  
Heidi Mangus ◽  
Erin McCourt ◽  
...  
Keyword(s):  
Clinical Trials ◽  
Human Plasma ◽  
Internal Standard ◽  
Clinical Samples ◽  
Isocitrate Dehydrogenase 1 ◽  
Bioanalytical Method ◽  
Molecule Inhibitor ◽  
Chiral Lc ◽  
First Time

Aim: Ivosidenib is a potent and selective small molecule inhibitor of mutant isocitrate dehydrogenase 1. Accurate measurement of ivosidenib is the key to ivosidenib pharmacokinetics in clinical trials. Materials & methods: Quantitation of ivosidenib was conducted by using a stable isotope labeled compound (ivosidenib-d4) as the internal standard. Results: This assay was validated and successfully applied to support multiple clinical trials. Selected clinical samples were also tested by a chiral LC–MS/MS method against four ivosidenib isomer standards to exclude the possibility of in vivo racemization of ivosidenib. Conclusion: A robust LC–MS/MS method was validated for ivosidenib in human plasma. This is the first time for ivosidenib bioanalytical method in any human matrix to be reported.

A simple equation to correct for gadolinium interference on plasma selenium measurement using inductively coupled plasma mass spectrometry

2020 ◽  
Vol 57 (3) ◽  
pp. 234-241
Author(s):  
Scott Wilschefski ◽  
Matthew Baxter ◽  
Gertruida Pool
Keyword(s):  
Mass Spectrometry ◽  
Inductively Coupled Plasma ◽  
Clinical Samples ◽  
Resonance Imaging ◽  
Simple Method ◽  
Plasma Selenium ◽  
Inductively Coupled ◽  
Icp Ms ◽  
Plasma Mass Spectrometry ◽  
Delays In Diagnosis

Background The measurement of selenium in human plasma is useful to assess deficiency or toxicity. The presence of gadolinium in clinical samples following administration of certain contrast agents used for magnetic resonance imaging can cause a significant positive bias in selenium results when measured using quadrupole inductively coupled plasma mass spectrometry (Q-ICP-MS). Methods A mathematical equation to correct for gadolinium interference was assessed using both patient samples and commercial quality control/external quality assurance (QC/EQA) materials spiked with gadolinium. Samples were analysed using an Agilent 7900 ICP-MS operated in ‘narrow peak’ (half-mass) mode. Accuracy was evaluated by comparing corrected selenium results with target concentrations. Results Corrected results were found to be accurate at all gadolinium concentrations tested (2, 4, 10 and 20 mg/L). Average recoveries ranged from 97.4 to 106.5%. Results for QC/EQA materials were within specified target ranges. Within-run imprecision was <3%, and between-run imprecision was <4.3%, demonstrating robustness. Conclusions The correction equation described here is a simple method to correct for gadolinium interference on plasma selenium measurement using ICP-MS. This approach eliminates the need for specimen recollections, and improves patient care by reducing laboratory turnaround times and preventing delays in diagnosis/treatment.

Sign in / Sign up

Export Citation Format

Share Document