scholarly journals Simultaneous Quantification of Apolipoprotein A-I and Apolipoprotein B by Liquid-Chromatography–Multiple- Reaction–Monitoring Mass Spectrometry

2010 ◽  
Vol 56 (12) ◽  
pp. 1804-1813 ◽  
Author(s):  
Sean A Agger ◽  
Luke C Marney ◽  
Andrew N Hoofnagle

BACKGROUND If liquid-chromatography–multiple-reaction–monitoring mass spectrometry (LC-MRM/MS) could be used in the large-scale preclinical verification of putative biomarkers, it would obviate the need for the development of expensive immunoassays. In addition, the translation of novel biomarkers to clinical use would be accelerated if the assays used in preclinical studies were the same as those used in the clinical laboratory. To validate this approach, we developed a multiplexed assay for the quantification of 2 clinically well-known biomarkers in human plasma, apolipoprotein A-I and apolipoprotein B (apoA-I and apoB). METHODS We used PeptideAtlas to identify candidate peptides. Human samples were denatured with urea or trifluoroethanol, reduced and alkylated, and digested with trypsin. We compared reversed-phase chromatographic separation of peptides with normal flow and microflow, and we normalized endogenous peptide peak areas to internal standard peptides. We evaluated different methods of calibration and compared the final method with a nephelometric immunoassay. RESULTS We developed a final method using trifluoroethanol denaturation, 21-h digestion, normal flow chromatography-electrospray ionization, and calibration with a single normal human plasma sample. For samples injected in duplicate, the method had intraassay CVs <6% and interassay CVs <12% for both proteins, and compared well with immunoassay (n = 47; Deming regression, LC-MRM/MS = 1.17 × immunoassay − 36.6; Sx|y = 10.3 for apoA-I and LC-MRM/MS = 1.21 × immunoassay + 7.0; Sx|y = 7.9 for apoB). CONCLUSIONS Multiplexed quantification of proteins in human plasma/serum by LC-MRM/MS is possible and compares well with clinically useful immunoassays. The potential application of single-point calibration to large clinical studies could simplify efforts to reduce day-to-day digestion variability.

2014 ◽  
Vol 60 (2) ◽  
pp. 353-360 ◽  
Author(s):  
Lynn Carr ◽  
Anne-Laure Gagez ◽  
Marie Essig ◽  
François-Ludovic Sauvage ◽  
Pierre Marquet ◽  
...  

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.


Author(s):  
Narottam Pal ◽  
Avanapu Srinivasa Rao ◽  
Pigilli Ravikumar

<p><strong>Objective</strong>:<strong> </strong>To develop a new method and validate the same for the determination of Febuxostat (FBS) in human plasma by liquid chromatography–mass spectrometry (LCMS).</p><p><strong>Methods</strong>:<strong> </strong>The present method utilized reversed-phase high-performance liquid chromatography with tandem mass spectroscopy. Febuxostat D9 (FBS D9) was used as internal standard (IS). The analyte and internal standard were separated from human plasma by using solid phase extraction method. Zorbax Eclipse XDB, C<sub>8</sub>, 100 mm x 4.6 mm, 3.5 µm column was used and HPLC grade acetonitrile, 5 millimolar (mM) ammonium format (80: 20, v/v) as mobile phase, detected by mass spectrometry operating in positive ion and multiple reaction monitoring modes.</p><p><strong>Results</strong>:<strong> </strong>The parent and production transitions for FBS and internal standard were at m/z 317.1→261.0 and 326.1→262.0 respectively. The method was validated for system suitability, specificity, carryover effect, linearity, precision, accuracy, matrix effect, sensitivity and stability. The linearity range was from 20.131 ng/ml to10015. 534 ng/ml with a correlation coefficient of 0.999. Precision results (%CV) across six quality control samples were within the limit. The percentage recovery of FBS and internal standard from matrix samples was found to be 76.57% and 75.03% respectively.</p><p><strong>Conclusion</strong>:<strong> </strong>Present study describes new LC-MS method for the quantification of FBS in a pharmaceutical formulation. According to validation results, it was found to be a simple, sensitive, accurate and precise method and also free from any kind of interference. Therefore the proposed analytical method can be used for routine analysis for the estimation of FBS in its formulation.</p>


2020 ◽  
Vol 10 (1) ◽  
pp. 108
Author(s):  
Hohyun Kim ◽  
Yunkyoung Choi ◽  
Yongwun An ◽  
Young-Rim Jung ◽  
Jin-Yong Lee ◽  
...  

It has been recognized that p-Coumaric acid (p-CA) has protective effects as an antioxidant, anti-inflammatory agent. A sensitive and efficient Liquid Chromatography-Mass Spectrometry (LC-MS) method for maximum determination of p-CA in human plasma has been established using Ultra-performance liquid Chromatography-tandem mass Spectrometry (UPLC-MS/MS). This study provides the developed analysis of p-CA extracted from Bambusae Caulis in Taeniam (BC) to examine the improvement of the treatment p-CA, IGF-1 and Osteocalcin level in human children which are important factors on the growth of children’s height through Pharmacokinetics/Pharmacodynamics (PK/PD) model. p-CA and internal standard in a plasma sample were detected by the Multiple Reaction Monitoring (MRM) scan mode with positive ion detection. The sample participating in the study was made of 34 subjects (placebo = 18, treatment = 16). The subjects were enrolled to be randomized to the control group and BC group. Randomized subjects took tested treatment twice a day, three capsules with oral administration (258 mg/capsule) each time after a meal. Standard calibration curves (reproducibility) were constructed and the lower limit of quantitation (LLOQ) for p-CA was found to be 0.2 ng/mL on injection of the sample into the UPLC-MS/MS system. Accuracy and precision were evaluated and the intra-accuracy was 99.2–103.8% with precision of 1.0–5.6% and inter-accuracy was 99.6–108.4% and precision of 1.3–6.4% for p-CA. The method has been successfully applied to PK/PD studies of p-CA in human plasma. The p-CA, BC in Taeniam extract increased the level of IGF-1 and Osteocalcin, and changed the height from baseline, which suggested that the p-CA could play an important role in longitudinal bone growth. Therefore, the p-CA extracted from BC in Taeniam might be a good alternative medicine to growth hormone (GH) therapy.


Author(s):  
Revathi Naga Lakshmi Ponnuri ◽  
Prahlad Pragallapati ◽  
Ravindra N ◽  
Venkata Basaveswara Rao Mandava

  Objective: The main objective of the work was to develop a straightforward, fast and selective liquid chromatography/tandem mass spectrometry (LC-MS/MS) assay for determination of pioglitazone (PG), keto pioglitazone (KPG), and hydroxy pioglitazone (HPG) in human plasma and to validate as per recent guidelines.Methods: Analyte and the internal standard (IS) were extracted from plasma through liquid-liquid extraction and chromatographed on a Xterra RP18, 100×4.6, 5 μ column using methanol: acetonitrile mixture and 10 mM Ammonium formate buffer (70:30, v/v) as the mobile phase at a flow rate of 0.7 mL/min. The API-3200 Q Trap LC-MS/MS instrument in multiple reaction monitoring mode was used for detection. Diphenhydramine was utilized as IS.Results: The linearity was established in the concentration range of 20.15-1007.58 ng/mL for PG, 20.35-1017.58 ng/mL for KPG, and 19.68-491.22 ng/mL for HPG in human plasma. All the validation parameters were well within the acceptance limits.Conclusion: A new simple LC-MS/MS method was developed for the determination of PG, KPG, and HPG in human plasma. This method can be easily applied for the estimation of pharmacokinetic parameters of PG, KPG, and HPG.


Author(s):  
Rajeev Kumar Gupta ◽  
Anand Chaurasia ◽  
Brijeshkunvar Mishra

Objective: A simple, sensitive and rapid performance liquid chromatography/positive ion electrospray tandem mass spectrometry method was to be developed and validated for quantification of propafenone (PPF) and its two major metabolite 5-hydroxy propafenone (5-OHP) and N-depropyl propafenone (NDP) in human plasma.Methods: Liquid-liquid extraction (LLE) with ethyl acetate was used of extraction of plasma samples. The analytes were separated using an isocratic mixture of 0.1% formic acid/acetonitrile (20:80 v/v) on a reversed-phase column Hypurity Advance C18 50 x2.1 mm, 5µ and analysed by mass spectrometry in the multiple reaction monitoring mode using the respective [M+H] Ions. The m/z was 342.20/116.10 for propafenone, m/z 299.80/74.10 for N depropyl propafenone and m/z 358.30/98.10 for 5-hydroxy propfenone along with m/z 409.2/238.0 for Amlodipine as internal standard respectively.Results: The method had a short chromatographic run time of 1.5 min. The method exhibited a linear dynamic range over 5.11 to 1000.73 ng/ml for propafenone, 0.51 to 100.06 ng/ml for N-depropyl propafenone and 5.11 to 1001.64 ng/ml for 5-hydroxy propafenone respectively, in human plasma.Conclusion: The validated method has been successfully used to analyze human plasma samples for application in pharmacokinetics, bioavailability and bioequivalence studies.


Author(s):  
DEEPAN T ◽  
BASAVESWARA RAO MV ◽  
DHANARAJU MD

Objective: A validated liquid chromatography–tandem mass spectrometry (LC–MS/MS) method was developed for canagliflozin in human plasma along with stability studies. Methods: The chromatographic separation of canagliflozin was performed on Zorbax XDB phenyl (75 × 4.6 mm, 3.5 mm) using methanol:acetate buffer (80:20 v/v) at a flow rate of 1.0 ml/min. The LC–MS/MS system consists of API 4000 triple quadrupole mass spectrometer equipped with turbospray ionization and an AS8020 automatic sample injector. Results: The retention time of canagliflozin was 1.15 min and total runtime was 2 min. The multiple reaction monitoring was 462.5/267.1 (m/z) for canagliflozin and 466.4/267.2 (m/z) for internal standard (canagliflozin D4), respectively. The method was linear over the range of 10–7505 ng/ml. The calculated slope ranged from 0.0451 to 0.0502 and intercepts from 0.0102 to 0.0456 with coefficients of the determination of 0.9970. The overall mean recovery of internal standard and canagliflozin was 76.66 and 79.77, respectively. Conclusion: The method was successfully validated and it was found to be within the limits for accuracy, precision, and linearity and it is stable under analytical conditions used.


2014 ◽  
Vol 50 (3) ◽  
pp. 543-550 ◽  
Author(s):  
Suéllen Cristina Rennó Silva ◽  
Gustavo Rodrigues de Rezende ◽  
Vanessa Bergamin Boralli

A simple, rapid, and sensitive method based on liquid chromatography-tandem mass spectrometry for the quantitative determination of simvastatin in human plasma was developed and validated. After a simple extraction with methyl tert-butyl ether, the analyte and internal standard (lovastatin) were analyzed using reverse-phase liquid chromatography, on a Kinetex C18column (100 × 4.6 mm, 2.6 μm) using acetonitrile: ammonium acetate (2 mM + 0.025 % formic acid) (70: 30, v/v) as a mobile phase in a run time of 3.5 min. Detection was carried out using electrospray positive ionization mass spectrometry in the multiple-reaction monitoring mode. The method was linear over 0.04-40.0 ng/mL concentration range. The mean extraction recovery of simvastatin was 82% (RSD within 15%). Intraday and interday precisions (as relative standard deviation) were all ≤8,7% with accuracy (as relative error) of ±8%. This rapid and reliable method was successfully applied for a bioequivalence study of 40 mg of simvastatin orally disintegrating tablets in 44 healthy volunteers, showing that this method is suitable for the quantification of simvastatin in human plasma samples for pharmacokinetics and bioequivalence studies.


2014 ◽  
Vol 2014 ◽  
pp. 1-7 ◽  
Author(s):  
Yunliang Zheng ◽  
Xingjiang Hu ◽  
Jian Liu ◽  
Guolan Wu ◽  
Huili Zhou ◽  
...  

A highly sensitive, simple, and rapid liquid chromatography tandem mass spectrometry method to simultaneously determine blonanserin and blonanserin C in human plasma with AD-5332 as internal standard (IS) was established. A simple direct protein precipitation method was used for the sample pretreatment, and chromatographic separation was performed on a Waters XBridge C8(4.6×150 mm, 3.5 μm) column. The mobile phase consists of a mixture of 10 mM ammonium formate and 0.1% formic acid in water (A) and 0.1% formic acid in methanol (B). To quantify blonanserin, blonanserin C, and IS, multiple reaction monitoring (MRM) was performed in positive ESI mode. The calibration curve was linear in the concentration range of 0.012–5.78 ng·mL−1for blonanserin and 0.023–11.57 ng·mL−1for blonanserin C (r2>0.9990). The intra- and interday precision of three quality control (QC) levels in plasma were less than 7.5%. Finally, the current simple, sensitive, and accurate LC-MS/MS method was successfully applied to investigate the pharmacokinetics of blonanserin and blonanserin C in healthy Chinese volunteers.


Sign in / Sign up

Export Citation Format

Share Document