High-throughput quantification of perindopril in human plasma by liquid chromatography/tandem mass spectrometry: application to a bioequivalence study

Preparation of Antihypertensive Drugs in Biological Matrix with Solvent Front Position Extraction for LC–MS/MS Analysis

Solvent front position extraction procedure was used to prepare biological samples containing selected antihypertensive drugs (ramipril, lercanidipine, indapamide, valsartan, hydrochlorothiazide, perindopril, and nebivolol). Substances separated from the biological matrix components (bovine serum albumin) were quantified by means of liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS). Sample preparation process was performed with the use of a prototype horizontal chamber with a moving pipette driven by a 3D printer mechanism enabling a controlled eluent flow velocity. Application of this device was advantageous for simultaneous preparation of several samples for further quantitative analysis, with a synchronized reduction of manual operations and solvent consumption. Quantitative results obtained for the majority of the investigated antihypertensive drugs in a complex biological matrix were satisfactory. The values of the %RSD were around 5% for six of the seven substances (with the exception of indapamide). The method exhibits a suitable accuracy (the relative error percentage was below 10% for most drugs). The values of LOD and LOQ were in the range of 1.19 µg/L–8.53 µg/L and 3.61 µg/L–25.8 µg/L, respectively.

Simultaneous determination of indapamide, perindopril and its active metabolite perindoprilat in human plasma using UPLC-MS/MS method

Lots of studies showed the combination therapy of perindopril, indapamide and amlodipine could increase BP lowering efficacy and the benefits of high-risk patients. To evaluate potential pharmacokinetic interaction, a simultaneous UPLC-MS/MS quantification method of perindopril, perindoprilat and indapamide in human plasma was developed and validated. The plasma samples were prepared by solid phase extraction, and then separated on an X-terra MS C₁₈ (2.1 mm × 150 mm, 3.5 μm) with isocratic elution. The ion transitions at m/z 369.165 → 172.000 (perindopril), m/z 341.146 → 170.112 (perindoprilat), m/z 366.010 → 132.100 (indapamide), m/z 389.120 → 206.200 (S10211-1, IS1) and m/z 394.080 → 160.200 (S1641, IS2) were monitored under the positive ion mode of electrospray ionization with multiple reaction monitoring. This method exhibited great sensitivity, linearity, accuracy, and precision for the determination of perindopril, perindoprilat and indapamide over the range of 0.250-50.0 ng/mL. The average extraction recovery of perindopril, perindoprilat and indapamide samples at low, medium, and high concentration levels were between 85.9% and 93.6%, respectively. The stability of analytes over different storage and processing conditions in the whole study was also validated. The method is fast, accurate, sensitive and reproducible, which is suitable for the detection of the concentration of perindopril, perindoprilat and indapamide in human plasma.

Simultaneous determination of indapamide, perindopril and perindoprilat in human plasma or whole blood by UPLC-MS/MS and its pharmacokinetic application

Simple and sensitive methods were developed for the determination of indapamide, perindopril and its active metabolite perindoprilat in human plasma or whole blood by hyphenated ultra-performance liquid chromatography-mass spectrometry (UPLC-MS/MS). Indapamide-d3, perindopril-d4 and perindoprilat-d4 were used as the internal standards. The separation was performed on a Thermo BDS Hypersil C₁₈ column (4.6 mm × 100 mm, 2.4 µm) for indapamide and perindopril simultaneously following a protein precipitation pretreatment of the biosamples. The separation of perindoprilat was achieved independently on a phenomenex PFP column (4.6 mm × 150 mm, 5 µm). All the analytes were quantitated with positive electrospray ionization and multiple reactions monitoring mode. The assay exhibited a linear range of 1–250 ng/mL for indapamide, 0.4–100 ng/mL for perindopril and 0.2–20 ng/mL for perindoprilat. The methods were fully validated to meet the requirements for bioassay in accuracy, precision, recovery, reproducibility, stabilities and matrix effects, and successfully applied to the pharmacokinetic study of perindopril tert-butylamine/indapamide compound tablets in Chinese healthy volunteers and the comparative pharmacokinetic study between plasma and whole blood.

A new LC-MS/MS bioanalytical method for perindopril and perindoprilat in human plasma and milk

A first of its kind, simple, rapid, and sensitive liquid chromatography mass spectrometry (LC-MS/MS) method was developed and validated for quantification of perindopril and perindoprilat in both human plasma and breast milk. The analytes and internal standards (phenazone and acetyl salicylic acid) were extracted from biological matrices by protein precipitation. A Phenomenex® C-18 column was used to provide an appropriate chromatographic separation of the analytes, followed by detection with tandem mass spectrometry. Gradient chromatographic and mass spectrometric detection conditions with mobile phases (A: 5% methanol + 0.1% formic acid in water v/v, and B: 95% methanol + 0.1% formic acid in water v/v) were developed to achieve a LOQ of 0.5 ng/mL in both human plasma and milk. The method was suitable of evaluating clinical samples. The mass transition was followed as m/z 369.10/172.00 for perindopril, m/z 339.00/168.10 for perindoprilat, m/z 188.90/55.95 for phenazone, and m/z 179.04/137.02 for acetyl salicylic acid. The developed method was optimized and validated with a linear range of 0.1-200 ng/mL (r ² = better than 0.99 for both perindopril and perindoprilat). The precision and accuracy values were within 15% CV. The overall recovery of the analytes was 80-110%. The method has good specificity and repeatability. Stability studies were conducted in both human plasma and bovine milk for up to 3 months, at the storage conditions of 25, 4, and -80 °C.

High-throughput quantification of 8 antihypertensive drugs and active metabolites in human plasma using UPLC-MS/MS

BACKGROUND

To assess drug adherence of patients with hypertension, an analytical method was developed and validated using ultra performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS). The method includes eight frequently prescribed antihypertensive drugs from four classes and their active metabolites: angiotensin converting enzyme inhibitors enalapril and perindopril (active metabolites respectively enalaprilate and perindoprilate), angiotensin II receptor blockers losartan (with the active metabolite losartan carboxylic acid) and valsartan, calcium channel blockers amlodipine and nifedipine and diuretics hydrochlorothiazide and spironolactone (with the active metabolite canrenone).

METHODS

The antihypertensive drugs were analyzed using a simple and fast sample preparation protocol with protein precipitation followed by chromatographic separation using a gradient elution on a reversed phase column. Mass spectrometric detection was conducted by applying both positive and negative electrospray ionization (ESI+/ESI-) and selected reaction monitoring mode (MS/MS). Only 50μl of plasma sample is needed for the simultaneous quantification of all 12 compounds within 6min run-to-run analysis time. Enalapril-d5 was applied as internal standard for all compounds except hydrochlorothiazide (internal standard: Hydrochlorothiazide-13C,d2).

RESULTS

The method was validated according to FDA guidelines. Matrix effects were examined using the method of Matuszewski. Correlation coefficients were higher than 0.995 for all compounds. Intra- and inter-day accuracies were <15% for all analytes except spironolactone (-16.8%) in the established linear range. Intra- and inter-day precision were <15% for all analytes. As a result of the lower sensitivity of hydrochlorothiazide, the lowest three calibration levels were excluded.

DISCUSSION/CONCLUSIONS

The described method is suitable for the simultaneous quantitative analysis of the most commonly used antihypertensive drugs and their corresponding active metabolites. Major advantages are minimal sample volume and clean up and a short runtime. The method is now available to monitor drug adherence of patients with resistant hypertension in our hospital.

A new LC-MS/MS bioanalytical method for atenolol in human plasma and milk

AIM

A new sensitive LC-MS/MS method for the quantification of atenolol in human plasma and milk has been developed for clinical lactation studies.

METHODS & RESULTS

Atenolol and the internal standard, phenazone, were extracted from biological matrices by protein precipitation. A Phenomenex^® C-18 column and gradient chromatographic conditions were used for separation of the analyte, followed by detection with MS. Stability of samples was confirmed for atenolol in human plasma and milk for up to 3 months. Linearity range of 1-800 ng/ml (r² = 0.9995), the precision within 15% CV and the recovery of the analyte (80-100% range) were achieved.

CONCLUSION

A new validated analytical method for atenolol in plasma and milk was developed.

Method development and validation of HPLC tandem/mass spectrometry for quantification of perindopril arginine and amlodipine besylate combination in bulk and pharmaceutical formulations

A well-characterized and fully validated ultra-high performance liquid chromatography-electrospray ionization-tandem mass spectrometric (UHPLC-ESI-MS/MS) method was developed to reliably analyze combination of perindopril arginine and amlodipine besylate in bulk and tablet formulations. The chromatographic separation was achieved on a Waters ACQUITY UPLC^® BEH C18 column with 1.7 μm particle packing which enabled the higher peak capacity, greater resolution, increased sensitivity, and higher speed of analysis using a volatile mobile phase ideally being at least 2 pH units below and above the perindopril arginine and amlodipine besylate pKa, respectively. Mass spectrometric detection was performed using electrospray ion source in positive ion polarity to profile the abundances of perindopril arginine and amlodipine besylate, using the transitions m/z 369 → m/z 172, and m/z 409 → m/z 238 for perindopril arginine and amlodipine besylate, respectively. Calibration curve was constructed over the range 0.25 – 500 ng/mL and 1.0 – 100 ng/mL for perindopril arginine and amlodipine besylate, respectively. The method was precise and accurate, and provided recovery rates > 80% for both compounds. Furthermore, the intra- and inter-assay precision in terms of % RSD was in between 0.1 – 3.7 for both perindopril arginine and amlodipine besylate. A specific, accurate, and precise UHPLC-MS/MS method for the determination of perindopril arginine and amlodipine besylate in bulk and tablet formulation.

Selective spectrofluorimetric method for the determination of perindopril erbumine in bulk and tablets through derivatization with dansyl chloride

Background

Perindopril erbumine is an antihypertensive, which belongs to the category of angiotensin-converting enzyme inhibitors (ACE inhibitors) that inhibit the conversion of angiotensin I to angiotensin II.

Methods

A new, selective, and sensitive spectrofluorimetric method was developed for the determination of perindopril erbumine based on the reaction with dansyl chloride in alkaline medium to give a highly fluorescent derivative which was measured at 496 nm after excitation at 340 nm in dichloromethane. The reaction conditions were studied and optimized.

Results

Under the optimum conditions, the fluorescence intensity was linear over a concentration range of 1.0 to 21.0 μg/mL (R 2 = 0.9997) with a detection limit of 0.242 μg/mL. In order to validate the method, the results were compared with those obtained by a high performance liquid chromatography method.

Conclusions

The proposed method was successfully applied to the analysis of perindopril erbumine in pure form and tablets with good precision and accuracy as revealed by t- and F tests. The mechanism of the reaction has also been discussed.

Novel Spectrofluorimetric Method for the Determination of Perindopril Erbumine Based on Fluorescence Quenching of Rhodamine B

A novel, simple and specific spectrofluorimetric method was developed and validated for the determination of perindopril erbumine (PDE). The method is based on the fluorescence quenching of Rhodamine B upon adding perindopril erbumine. The quenched fluorescence was monitored at 578 nm after excitation at 500 nm. The optimization of the reaction conditions such as the solvent, reagent concentration, and reaction time were investigated. Under the optimum conditions, the fluorescence quenching was linear over a concentration range of 1.0-6.0 μg/mL. The proposed method was fully validated and successfully applied to the analysis of perindopril erbumine in pure form and tablets. Statistical comparison of the results obtained by the developed and reference methods revealed no significant differences between the methods compared in terms of accuracy and precision. The method was shown to be highly specific in the presence of indapamide, a diuretic that is commonly combined with perindopril erbumine. The mechanism of rhodamine B quenching was also discussed.

Novel Spectrofluorimetric Method for the Determination of Perindopril Erbumine Based on Charge Transfer Reaction with 7-Hydroxycoumarin

A novel, simple, selective and sensitive spectrofluorimetric method was developed and validated for the determination of perindopril erbumine using 7-hydroxycoumarin. Perindopril erbumine was found to react with 7-hydroxycoumarin in acetonitrile resulting in a new fluorescent product with about 58 nm blue shifted emission. The fluorescence of the complex was measured at 440 nm after excitation at 350 nm in acetonitrile. Under the optimum conditions, the fluorescence intensity was linear over a concentration range of 2.0-16.0 μg/mL (R(2) = 1) with a detection limit of 0.054 μg/mL. The proposed method was fully validated and successfully applied to the analysis of perindopril erbumine in pure form and tablets. Statistical comparison of the results obtained by the proposed and reference method revealed no significant differences in the performance of the two methods regarding the accuracy and precision respectively. The method was shown to be highly specific in the presence of indapamide, a diuretic that is commonly combined with perindopril erbumine. A proposal for the reaction pathway with 7-hydroxycoumarin was postulated.

Stability-indicating RP-HPLC method for the quantitative analysis of perindopril erbumine in tablet dosage form

A specific, stability-indicating reversed-phase high-performance liquid chromatography (RP-HPLC) method was developed and validated for the estimation of perindopril erbumine (PDE) in tablet dosage form. The HPLC method showed adequate separation of PDE from its degradation products. The separation was achieved on a Phenomenex Luna C18 column (250 × 4.6 mm × 5 µm) using a mobile phase composition of 0.2% trifluoroacetic acid buffer and acetonitrile in the ratio of 60:40 (pH adjusted to 3 with ammonia) at a flow rate of 1 mL/min. The injection volume was 20 µL and the wavelength of detection was kept at 215 nm. Stress studies were performed with 1 mg/mL of each drug, starting with mild conditions and followed by stronger conditions to achieve sufficient degradation at approximately 5-20%. The linearity of the proposed method was investigated in the range of 2.5 to 50 µg/mL for PDE. The limits of detection and quantification were found to be 0.75 and 2.3 µg/mL, respectively.

Quantification of pseudoephedrine in human plasma by LC-MS/MS using mosapride as internal standard

A simple, sensitive and rapid high-performance liquid chromatography/positive ion electrospray tandem mass spectrometry (LC-MS/MS) method was developed and validated for the quantification of pseudoephedrine in human plasma using mosapride as internal standard. Following solid-phase extraction, the analytes were separated using an isocratic mobile phase on a reverse-phase column and analyzed by MS/MS in the multiple-reaction monitoring mode using the respective [M + H](+) ions, m/z 166/148 for pseuoephedrine and m/z 422/198 for the IS. The method exhibited a linear dynamic range of 2-1000 ng/mL pseudoephedrine in human plasma. The lower limit of quantification was 2 ng/mL with a relative standard deviation of less than 9% for pseudoephedrine. Acceptable precision and accuracy were obtained for concentrations over the standard curve range. The total chromatographic run time of 2 min for each sample made it possible to analyze more than 400 human plasma samples per day. The validated method has been successfully used to analyze human plasma samples for application in pharmacokinetic, bioavailability or bioequivalence studies.

A rapid method for quantitatively estimating metabolites in human plasma in the absence of synthetic standards using a combination of liquid chromatography/mass spectrometry and radiometric detection

An approach to estimating the levels of drug-related metabolites in human plasma in the absence of synthesized chemical standards has been developed. High-performance liquid chromatography/mass spectrometry (LC/MS) in combination with radiometric detection was used in this method. Biologically derived [(14)C] metabolites from preclinical in vitro and in vivo matrices are used as [(14)C] metabolite standards and their concentrations in matrices are calculated based on the corresponding radioactivity. The amount of drug-related metabolites in human plasma samples can be estimated by determining relative MS responses of metabolites between plasma and [(14)C] metabolite standards, and using the calculated concentrations of metabolite standards as calibrants. An example for the estimation of metabolites in human plasma was used to demonstrate the utility of this methodology.

Simultaneous determination of losartan, EXP-3174 and hydrochlorothiazide in plasma via fully automated 96-well-format-based solid-phase extraction and liquid chromatography–negative electrospray tandem mass spectrometry

An automated, sensitive and high-throughput liquid chromatographic/electrospray tandem mass spectrometric (LC-MS/MS) assay was developed for the simultaneous determination of losartan (LOS), its major circulating metabolite EXP-3174 and hydrochlorothiazide (HCTZ) in human plasma. LOS and HCTZ coexist in the same drug formulation, and this is the first method that enables the simultaneous determination of both drugs along with the active metabolite of LOS. Since these drugs have different physicochemical properties, the employment of a liquid-liquid extraction (LLE) protocol was precluded. A fully automated solid-phase extraction (SPE) protocol, based on 96-well format plates, was used to isolate these compounds and furosemide (internal standard, IS) from plasma. Washing and elution steps were amended accordingly in order to minimize any matrix effect from components of the plasma without reducing the elution of the molecules of interest. The compounds were eluted from a C18 column and detected with an API 3000 triple-quadrupole mass spectrometer using negative electrospray ionization and multiple reaction monitoring (MRM). The assay was linear over the range 1.00-400 ng/mL for LOS and EXP-3174 and 0.500-200 ng/mL for HCTZ, respectively, when 200 microl of plasma was used in the extraction. The overall intra- and interassay variations were within acceptance limits. The analysis time for each sample was 4 min, and more than 300 samples could be analyzed in one day by running the system overnight. The assay was simple, highly sensitive, selective, precise, fast, and it enables the reliable determination of LOS, EXP-3174 and HCTZ in pharmacokinetic or bioequivalence studies after per os administration of a single tablet containing both drugs.