Quantification of pantoprazole in human plasma using LC-MS/MS for pharmacokinetics and bioequivalence study

Introducing of Li2FeMn3O8 /C-C3N4 /IL nanocomposite for electrochemical determination of pantoprazole sodium in real samples

A new electrochemical sensor based on Li₂FeMn₃O₈/C-C₃N₄ (LFMO/CCN)/1-ethyl-3-methylimidazolium chloride modified carbon paste electrode (CPE) has been constructed to measure pantoprazole sodium (PNZS). The electrochemical impedance spectroscopy (EIS) method was employed to evaluate the electrode charge-transfer resistances. Moreover, the differential pulse voltammetry method was used to detect PNZS in phosphate buffer solution (PBS) at pH 7.0. The detection limit of 80.0 × 10^-9 M and 10.9 × 10^-7 M was obtained under optimal conditions in the linear concentration range of PNZS 0.09-100 μM and 100-900 μM. Chronoampermetry technique was utilized to determine the diffusion coefficient (D) of PNZS on the modified electrode surface. The CCN/LFMO/IL/CPE was successfully used to determine PNZS in various drug formulations such as tablets and vials. Finally, simultaneous determination of PNZS and acetaminophen was accomplished with no interference based on the proposed sensor.

Targeted temperature management after cardiac arrest is associated with reduced metabolism of pantoprazole - A probe drug of CYP2C19 metabolism

OBJECTIVE

Targeted temperature management (TTM) is part of standard post-resuscitation care. TTM may downregulate cytochrome enzyme activity and thus impact drug metabolism. This study compared the pharmacokinetics (PK) of pantoprazole, a probe drug of CYP2C19-dependent metabolism, at different stages of TTM following cardiac arrest.

METHODS

This prospective controlled study was performed at the Medical University of Vienna and enrolled 16 patients following cardiac arrest. The patients completed up to three study periods (each lasting 24 h) in which plasma concentrations of pantoprazole were quantified: (P1) hypothermia (33 °C) after admission, (P2) normothermia after rewarming (36 °C, intensive care), and (P3) normothermia during recovery (normal ward, control group). PK was analysed using non-compartmental analysis and nonlinear mixed-effects modelling.

RESULTS

16 patients completed periods P1 and P2; ten completed P3. The median half-life of pantoprazole was 2.4 h (quartiles: 1.8-4.8 h) in P1, 2.8 h (2.1-6.8 h, p = 0.046 vs. P1, p = 0.005 vs. P3) in P2 and 1.2 h (0.9 - 2.3 h, p = 0.007 vs. P1) in P3. A two-compartment model described the PK data best. Typical values for clearance were estimated separately for each study period, indicating 40% and 29% reductions during P1 and P2, respectively, compared to P3. The central volume of distribution was estimated separately for P2, indicating a 64% increase compared to P1 and P3.

CONCLUSION

CYP2C19-dependent drug metabolism is downregulated during TTM following cardiac arrest. These results may influence drug choice and dosing of similarly metabolized drugs and may be helpful for designing studies in similar clinical situations.

Synchronous LC-MS/MS determination of pantoprazole and amitriptyline in rabbit plasma: application to comparative in vivo pharmacokinetic study of novel formulated effervescent granules with its marketed tablet dosage form

In the present study the bioavailability and pharmacokinetics properties of pantoprazole (proton pump inhibitor)/amitriptyline (tricyclic antidepressant) in novel formulated effervescent granules was estimated in rabbit plasma using a validated, selective and rapid LC-MS/MS method. Separation and detection of pantoprazole, amitriptyline and internal standards namely omeprazole and dothiepin, respectively, were achieved at ambient column temperature on C₁₈. Acetonitrile: 4mM ammonium acetate solution (comprising 0.05 % formic acid) (40:60, v/v) was used as mobile phase and the flow rate of 0.6 mLmin^-1 was applied. Liquid-liquid extraction technique with diethyl ether: dichloromethane (70:30, v/v) was used to extract the cited drugs from rabbit plasma. Multiple reactions monitoring (MRM) in the positive ionization mode was carried out for quantification. The method was validated over linear concentration range of 0.01-4μgmL^-1 and 0.001-0.1 μgmL^-1 for Pan and Ami respectively, with regression coefficient (r²) ≥ 0.9961. The intra- and inter-run precisions (%CV) were ≤4.03. The extraction recoveries were in the range of 95.92%-100.24 %. Pan and Ami were stable during three freeze-thaw cycle and post-preparative stability. The work also aimed to formulate immediate release novel effervescent granules by melt granulation technique. Nine formulae were assessed by validated dissolution test for their micrometric properties and dissolution profile. Experimental design was applied to select formula that fulfilled the desired criteria of optimum release of pantoprazole and amitriptyline with optimum micrometric properties for the study. A single period randomized open-label parallel design was applied on Chancellor's rabbit. The selected formula showed superior pharmacokinetic parameters for pantoprazole and amitriptyline than that of marketed products.

HPLC–DAD method for investigating pantoprazole for its stress-dependent degradation by photolysis and oxidation

A reversed-phased high-performance liquid chromatography–diode-array detection (HPLC–DAD) method has been developed for investigating the stress-dependent degradation of pantoprazole (PTZ) by a photolytic and oxidative mechanism. The developed method separated PTZ from its degradation products on a C18 column with a mobile phase consisted of methanol and water (60:40, v/v; pH 3.0) at a flow rate of 1 mL/min. The linear regression coefficient of 0.9995 was obtained for a concentration range from 5 to 25 μg/mL. The % relative standard deviation for repeatability and intermediate precision were below 0.5% and 1.5%, respectively, while the sensitivity of the method was demonstrated by a limit of detection value of 0.25 μg/mL. The stress sample analyses for PTZ results revealed the formation of a total of 18 degradation products, and out of them, 9 degradation products were common for both photolytic and oxidative degradations. Further, the oxidation by azobisisobutyronitrile produced the highest number of degradation products (11 impurities), 3 of which are more hydrophobic than PTZ. In photolytic degradation, 8 and 7 degradation products were observed with UV radiation and sunlight exposure, respectively. Furthermore, the degradation of pantoprazole sodium injection formulation was carried out under the same stress conditions, and it revealed the formation of 3 common impurities under both stress conditions, but other impurities were not detected in the formulations. Finally, 3 common impurities formed in formulations of PTZ injections, viz., sulfone, N-oxide, and N-oxide sulfone impurities, were identified by spike analyses.

A New Solid-Phase Extraction Method for Determination of Pantoprazole in Human Plasma Using High-Performance Liquid Chromatography

BACKGROUND:

A new simple, selective and accurate high-performance liquid chromatographic (HPLC) method utilising solid-phase extraction for the determination of pantoprazole in human plasma samples has been developed.

AIM:

The purpose of this paper was developing a new HPLC method suitable for the determination of pantoprazole in plasma samples, which enables simple and rapid isolation and concentration of the analysed drug.

METHODS:

The chromatographic separation was accomplished on a LiChroCart LiChrospher 60 RP select B column using a mobile phase composed of 0.2 % (V/V) water solution of triethylamine (pH 7) and acetonitrile (58:42, V/V) followed by UV detection was at 280 nm. The solid-phase extraction method using LiChrolut RP-18 (200 mg, 3 ml) was applied to the obtained good separation of investigated drug from endogenous plasma components. Best results were achieved when plasma samples were buffered with 0.1 mol/L KH2PO4 (pH 9) before extraction, eluted and reconstituted with acetonitrile and 0.001 mol/L NaOH after extraction, respectively.

RESULTS:

The standard calibration curves showed good linearity within the range of 25.0-4000.0 ng/mL with a correlation coefficient greater than 0.996. Retention times of pantoprazole and internal standard, lansoprazole was 4.1 and 6.0 min respectively. The limit of quantification was 25.0 ng/mL. For intra- and inter-day precision relative standard deviations ranged from 4.2 to 9.3%. The relative errors for stability investigations were ranged from 0.12 to -10.5%.

CONCLUSION:

This method has good precision and accuracy and was successfully applied to the pharmacokinetic and bioequivalence study of 40 mg pantoprazole in healthy volunteers.

Simultaneous Quantification of Pantoprazole and Levosulpiride in Spiked Human Plasma Using High Performance Liquid Chromatography Tandem Mass Spectrometry

Background:

Pantoprazole (PTZ) and Levosulpiride (LS) were proven as effective agents for the treatment of Gastro-Esophageal Reflux Disease (GERD). It is a complex motor disorder that results in regurgitation of the gastric contents into the lower esophagus with consequent symptoms such as heart burn, retrosternal pain, dysphagia and belching.

Methods:

A rapid, sensitive, selective and specific liquid chromatography- electro spray ionization tandem mass spectrometry (LC-MS/MS) method was developed for the simultaneous quantification of Pantoprazole (PTZ) and Levosulpiride (LS) in spiked Human Plasma. The method utilized SPE as sample preparation technique and the analysis was carried out on a HPLC system utilizing electro spray ionization as interface and triple quadrupole mass analyzer for quantification in MRM possitive mode. Iloperidone was used as internal standard (IS). Chromatographic separation was performed on a Phenomenex C-18 Column (4.6 mm x 50 mm, 5µ) with an isocratic elution mode utilizing a mobile phase composition of Solution containing a mixture of 70 volumes of acetonitrile: 30 volumes of methanol and 10mM ammonium formate (pH 4.0) at the ratio of 80:20 % v/v. The flow rate was maintained at 0.3 mL/min.

Results:

PTZ, LS and IS were detected and quantified with proton adducts at m/z 383.37→200.00, m/z 341.42→112.15 and 426.48→261.00 respectively. The linearity and range was established by fortifying blank plasma samples in the concentration range of 3.5-2000 ng/mL for PTZ and 3.0-2400 ng/mL for LS. The correlation coefficient (r2) was found to be ≥ 0.993 for PTZ and (r2) ≥ 0.990 for LS. The lower limit of quantification for PTZ was 3.5 ng/mL and LS was 3.0 ng/mL. The intra and inter day precision and accuracy for PTZ and LS were within the limits fulfilling the international acceptance criteria. PTZ and LS were found to be stable throughout three freeze-thaw cycles, bench top and short term stability studies.

Conclusion:

The proposed validated LC-MS/MS method offers a sensitive quantification of PTZ and LS in spiked human plasma and can be utilized for the quantification of PTZ and LS in real-time samples.

Clopidogrel in Critically Ill Patients

Only limited data are available regarding the treatment of critically ill patients with clopidogrel. This trial investigated the effects and the drug concentrations of the cytochrome P450 (CYP450) activated prodrug clopidogrel (n = 43) and the half‐life of the similarly metabolized pantoprazole (n = 16) in critically ill patients. ADP‐induced aggregometry in whole blood classified 74% (95% confidence intervals 59–87%) of critically ill patients as poor responders (n = 43), and 65% (49–79%) responded poorly according to the vasodilator‐stimulated phosphoprotein phosphorylation (VASP‐P) assay. Although the plasma levels of clopidogrel active metabolite normally exceed the inactive prodrug ∼30‐fold, the parent drug levels even exceeded those of the metabolite 2‐fold in critically ill patients. The half‐life of pantoprazole was several‐fold longer in these patients compared with reference populations. The inverse ratio of prodrug/active metabolite indicates insufficient metabolization of clopidogrel, which is independently confirmed by the ∼5‐fold increase in half‐life of pantoprazole. Thus, high‐risk patients may benefit from treatment with alternative platelet inhibitors.

Development and validation of a LC-MS/MS method for quantification of hetrombopag for pharmacokinetics study

Hetrombopag as the derivative of ethylidene hydrazine carboxamide was recently developed into a novel patented non-peptide thrombopoietin mimetic and thrombopoietin receptor agonist to treat idiopathic thrombocytopenic purpura. To study the pharmacokinetics of hetrombopag, a highly sensitive, rapid and reliable liquid chromatography-tandem mass spectrometry (LC–MS/MS) method was developed and validated for determination of hetrombopag in rat plasma. After protein precipitation extraction, the chromatography separation of analyte and internal standard named eltrombopag as an marketed analog of hetrombopag was performed on an Synergi Polar-RP column at the flow rate of 0.5 mL/min, and the determination was conducted on an API4000 triple quadrupole mass spectrometry in the multiple reaction monitoring mode using the respective [M+H]⁺ ions m/z 459.2 → 200.9 for hetrombopag and m/z 443.2 → 229.0 for IS. The lower limit of quantification was established to be 1 ng/mL, and the linear scope of standard curve was 1–1000 ng/mL. Both the precision (RSD%) and accuracy (RE%) were within the acceptable criterion of below 15 %. The validated method was successfully applied to quantify hetrombopag in the rat plasma and investigate the pharmacokinetics.

Simultaneous determination of a binary mixture of pantoprazole sodium and itopride hydrochloride by four spectrophotometric methods

Four simple, sensitive, accurate and precise spectrophotometric methods were developed for the simultaneous determination of a binary mixture containing Pantoprazole Sodium Sesquihydrate (PAN) and Itopride Hydrochloride (ITH). Method (A) is the derivative ratio method ((1)DD), method (B) is the mean centering of ratio spectra method (MCR), method (C) is the ratio difference method (RD) and method (D) is the isoabsorptive point coupled with third derivative method ((3)D). Linear correlation was obtained in range 8-44 μg/mL for PAN by the four proposed methods, 8-40 μg/mL for ITH by methods A, B and C and 10-40 μg/mL for ITH by method D. The suggested methods were validated according to ICH guidelines. The obtained results were statistically compared with those obtained by the official and a reported method for PAN and ITH, respectively, showing no significant difference with respect to accuracy and precision.

Analytical method development and validation of simultaneous estimation of rabeprazole, pantoprazole, and itopride by reverse-phase high-performance liquid chromatography

A simple, selective, rapid, and precise reverse-phase high-performance liquid chromatography (RP-HPLC) method for the simultaneous estimation of rabeprazole (RP), pantoprazole (PP), and itopride (IP) has been developed. The compounds were well separated on a Phenomenex C₁₈ (Luna) column (250 mm × 4.6 mm, dp = 5 μm) with C₁₈ guard column (4 mm × 3 mm × 5 μm) with a mobile phase consisting of buffer containing 10 mM potassium dihydrogen orthophosphate (adjusted to pH 6.8): acetonitrile (70:30 v/v) at a flow rate of 1.0 mL/min and ultraviolet detection at 288 nm. The retention time of RP, PP, and IP were 5.35, 7.92, and 11.16 minutes, respectively. Validation of the proposed method was carried out according to International Conference on Harmonisation (ICH) guidelines. Linearity range was obtained for RP, PP, and IP over the concentration range of 2.5–25, 1 –30, and 3–35 μg/mL and the r² values were 0.994, 0.978, and 0.991, respectively. The calculated limit of detection (LOD) values were 1, 0.3, and 1 μg/mL and limit of quantitation (LOQ) values were 2.5, 1, and 3 μg/mL for RP, PP, and IP correspondingly. Thus, the current study showed that the developed reverse-phase liquid chromatography method is sensitive and selective for the estimation of RP, PP, and IP in combined dosage form.

A Validated HPLC-DAD Method for Simultaneous Determination of Etodolac and Pantoprazole in Rat Plasma

A simple, sensitive, and accurate HPLC-DAD method has been developed and validated for the simultaneous determination of pantoprazole and etodolac in rat plasma as a tool for therapeutic drug monitoring. Optimal chromatographic separation of the analytes was achieved on a Waters Symmetry C18 column using a mobile phase that consisted of phosphate buffer pH~4.0 as eluent A and acetonitrile as eluent B in a ratio of A : B, 55 : 45 v/v for 6 min, pumped isocratically at a flow rate of 0.8 mL min−1. The eluted analytes were monitored using photodiode array detector set to quantify samples at 254 nm. The method was linear withr2=0.9999for PTZ andr2=0.9995for ETD at a concentration range of 0.1–15 and 5–50 μgmL−1for PTZ and ETD, respectively. The limits of detection were found to be 0.033 and 0.918 μgmL−1for PTZ and ETD, respectively. The method was statistically validated for linearity, accuracy, precision, and selectivity following the International Conference for Harmonization (ICH) guidelines. The reproducibility of the method was reliable with the intra- and interday precision (% RSD) <7.76% for PTZ and <7.58 % for ETD.