Enantioanalysis of Bisoprolol in Human Plasma with a Macrocyclic Antibiotic HPLC Chiral Column Using Fluorescence Detection and Solid Phase Extraction

Application of MEKC and UPLC with Fluorescence Detection for Simultaneous Determination of Amlodipine Besylate and Bisoprolol Fumarate

OBJECTIVE

Two chromatographic methods were described for simultaneous determination of the antihypertensive drugs amlodipine besylate (AML) and bisoprolol fumarate (BIS).

METHODS

Method I applies micellar electrokinetic capillary chromatography using a deactivated fused silica capillary (25 cm effective length × 50 μm internal diameter). The background electrolyte consisted of 0.01 M borate buffer (pH 9.2) containing 0.025 M sodium dodecyl sulphate and methanol in the ratio of 80:20 (v/v). Valsartan (VAL) was used as an internal standard. Diode array detector was set at 238, 224, and 210 nm for measuring AML, BIS, and VAL, respectively. Method II involves using ultra-performance liquid chromatography with fluorescence detection. Zorbax SB-C8 column (2.1 × 100 mm, 1.8 μm particle size) was used with isocratic elution of the mobile phase composed of 0.1% trifluoroacetic acid, acetonitrile, and methanol in the ratio of 55:35:10 (v/v) at a flow rate of 0.6 mL/min. Fluorescence detection was done using excitation wavelengths 230 and 370 nm and emission wavelengths 305 and 450 nm for BIS and AML, respectively. Validation parameters were carefully studied including linearity, ranges, precision, accuracy, robustness, detection, and quantification limits.

RESULTS

Method I showed good linearity over the range 10-100 μg/mL for both dugs. Method II's linear ranges were 0.001-0.1 and 0.02-1 µg/mL for BIS and AML, respectively.

CONCLUSION

The proposed methods were successfully validated and applied for assay of the studied drugs in their fixed-dose combination tablets.

HIGHLIGHTS

To the best of our knowledge, this study suggests the first electro-chromatographic and LC with fluorescence detection methods for simultaneous determination of amlodipine and bisoprolol.

Bisoprolol: A comprehensive profile

The present study describes a comprehensive profile of Bisoprolol including detailed nomenclature; formulae, elemental analysis, appearance, its uses, applications, and methods for the preparation are outlined. The profile contains physicochemical properties of Bisoprolol including pKa value, solubility, X-ray powder diffraction, and methods of analysis (including compendial, electrochemical, spectroscopic, chromatographic and capillary electrophoresis). The study also covers thermal analysis such as differential scanning calorimetry and thermogravimetry of Bisoprolol. Which gives a brief idea of melting point, glass transition as well as differentiation between anhydrous and hydrated forms. In addition to these functional groups and structural confirmation of bisoprolol also presented with the help of Fourier transform infrared spectrometry and nuclear magnetic resonance spectroscopy, respectively. The mass fragmentation pattern of bisoprolol fumarate was reported using the electrospray ionization technique. Some recently reported methods for pharmacokinetic analysis of bisoprolol using high-performance liquid chromatography as well as liquid chromatography-mass spectrometry were also included in the study.

High-Performance Liquid Chromatography Enantioseparations Using Macrocyclic Glycopeptide-Based Chiral Stationary Phases: An Overview

Since their introduction by Daniel W. Armstrong in 1994, antibiotic-based chiral stationary phases have proven their applicability for the chiral resolution of various types of racemates. The unique structure of macrocyclic glycopeptides and their large variety of interactive sites (e.g., hydrophobic pockets, hydroxy, amino and carboxyl groups, halogen atoms, aromatic moieties) are the reasons for their wide-ranging selectivity. The commercially available Chirobiotic™ phases, which display complementary characteristics, are capable of separating a broad variety of enantiomeric compounds with good efficiency, good column loadability, high reproducibility, and long-term stability. These are the major reasons for the frequent use of macrocyclic antibiotic-based stationary phases in HPLC enantioseparations.This overview chapter provides a brief summary of general aspects of antibiotic-based chiral stationary phases including their preparation and their application to direct enantioseparations of various racemates focusing on the literature published since 2004.

Significance and challenges of stereoselectivity assessing methods in drug metabolism

Stereoselectivity in drug metabolism can not only influence the pharmacological activities, tolerability, safety, and bioavailability of drugs directly, but also cause different kinds of drug-drug interactions. Thus, assessing stereoselectivity in drug metabolism is of great significance for pharmaceutical research and development (R&D) and rational use in clinic. Although there are various methods available for assessing stereoselectivity in drug metabolism, many of them have shortcomings. The indirect method of chromatographic methods can only be applicable to specific samples with functional groups to be derivatized or form complex with a chiral selector, while the direct method achieved by chiral stationary phases (CSPs) is expensive. As a detector of chromatographic methods, mass spectrometry (MS) is highly sensitive and specific, whereas the matrix interference is still a challenge to overcome. In addition, the use of nuclear magnetic resonance (NMR) and immunoassay in chiral analysis are worth noting. This review presents several typical examples of drug stereoselective metabolism and provides a literature-based evaluation on current chiral analytical techniques to show the significance and challenges of stereoselectivity assessing methods in drug metabolism.

Liquid chromatography-tandem mass spectrometry method for simultaneous quantification of bisoprolol, ramiprilat, propranolol and midazolam in rat dried blood spots

Dried blood spot (DBS) sampling represents a suitable method for pharmacokinetic studies in rats, particularly if serial sampling is needed. To study the pharmacokinetics of drugs in a rat heart failure (HF) model, we developed and validated a method for the simultaneous determination of bisoprolol, ramiprilat, propranolol and midazolam in DBS samples. Bisoprolol and ramipril are widely used in the treatment of HF, and midazolam and propranolol are markers of hepatic metabolism, which can be altered in HF. A 20μL sample of rat blood was pipetted onto Whatman 903 Protein Saver Card and allowed to dry. The whole spot was excised and 300μL of solvent (methanol with 10% ultrapure water and 0.1% formic acid) was added. After mixing and incubating the sample in an ultrasonic bath, a mixture of isotopically labeled internal standards was added. After centrifugation, the extracts were cleaned on an Ostro™ plate and analyzed using liquid chromatography-tandem mass spectroscopy. The method was successfully validated. No significant interference was observed in the retention times of analytes or internal standards. The intraday and interday accuracy and precision were within a ±15% interval. The method was linear in the range 5-250μg/L and the lower limit of quantification was 5μg/L for all four analytes. The absolute matrix effect ranged from 98.7% for midazolam to 121% for ramiprilat. The recovery was lowest for ramiprilat and highest for propranolol. Samples were stable at all tested temperatures. The method has been used successfully in a real-time pharmacokinetic study in rats.

Enantioseparations by high-performance liquid chromatography using macrocyclic glycopeptide-based chiral stationary phases: an overview

Since their introduction by Armstrong in 1994, macrocyclic antibiotic-based chiral stationary phases have proven their applicability for the chiral resolution of various types of racemates. The unique structure of macrocyclic glycopeptides and their large variety of interactive sites (e.g., hydrophobic pockets, hydroxyl, amino and carboxyl groups, halogen atoms, aromatic moieties, etc.) are the reason for their wide-ranging selectivity. The commercially available Chirobiotic™ phases, which display complementary characteristics, are capable of separating a broad variety of enantiomeric compounds with good efficiency, good column loadability, high reproducibility, and long-term stability. These are the major reasons for the use of macrocyclic antibiotic-based stationary phases in HPLC enantioseparations. This overview chapter provides a brief summary of general aspects of macrocyclic antibiotic-based chiral stationary phases including their preparation and their application to direct enantioseparations of various racemates focusing on the literature published since 2004.

Detection and quantitation of β-blockers in plasma and urine

β-blockers are a class of antihypertensive drugs that are used for the management of cardiac arrhythmias, cardioprotection after myocardial infarction (heart attack) and hypertension. They have revolutionized the medical management of angina pectoris and are recommended as first-line agents by national and international guidelines. Although β-blockers are still the cornerstone for the treatment of heart failure, some of the drugs in this category are prohibited in several sports requiring vehicle control and bodily movements as they reduce heart rate and tremors, and improve performance. As a result, urine analysis of β-blockers is mandatory in doping control and toxicological screening. The determination of plasma levels of β-blockers helps to ensure noncompliance in patients with persistent hypertonia to confirm the diagnosis of β-blocker poisoning and for therapeutic drug monitoring. This review provides a comprehensive account of various analytical methods developed for detection and quantitation of β-blockers in plasma and urine.

Torcetrapib for animal and human pharmacokinetic studies: applicability of chiral and achiral methodologies

The emergence of bioanalysis as a key tool in the drug-discovery and -development process has enabled the development of sensitive, precise and specific bioanalytical methods in recent years. These methods have enabled the progress of novel chemical entities through the life cycle of drug discovery and development. The focus of this review article is on a well-known cholesteryl ester transfer protein (CETP) inhibitor known as torcetrapib. Although torcetrapib was withdrawn from clinical development, it is important to understand the various bioanalytical methodologies (chiral and achiral) that are readily available for the pharmacokinetic/pharmacodynamic characterization of the drug. Additionally, these methodologies may be applicable to the bioanalysis of the next-generation CETP inhibitors. This review covers the development and validation of assay methods that were used to obtain preclinical and clinical pharmacokinetic parameters of torcetrapib. Accordingly, methods are available for the determination of torcetrapib in various species, namely dogs, hamsters, rats, mice, monkeys and humans. Since torcetrapib is a chiral compound, methods have been developed for stereoselective bioanalysis to evaluate in vivo chiral inversion phenomena. Interestingly, torcetrapib can be analyzed by various bioanalytical options (e.g., HPLC–UV, LC–MS, LC–MS/MS and GC–MS assays) depending on the type of species under consideration with the associated sensitivity requirements. This review covers all the available methodologies for torcetrapib, providing both assay-development and -optimization strategies. It also tabulates validation parameters and enumerates the difficulties, challenges and nuances of the various published assays for torcetrapib.