Determination of montelukast sodium in human plasma by column-switching high-performance liquid chromatography with fluorescence detection

Simultaneous Determination of Montelukast Sodium and Loratadine by Eco-Friendly Densitometry and Spectrophotometric Methods

Recently, the aim of analytical community is to reduce the usage of hazardous chemicals; so eco-friendly, rapid, selective and cost-effective methods were developed for simultaneous determination of montelukast sodium (MKT) and loratadine (LRT). The first method was based on chromatographic separation performed on precoated silica gel 60 GF254 plates with ethyl acetate-ethanol 9: 1 (v/v) as the mobile phase. The developed plates were scanned and quantified at 260 nm. The method gives linear correlation over concentration ranges of 0.3-3.6 μg/spot and 0.2-4.0 μg/spot for MKT and LRT, respectively. It was also successfully applied to analysis of both drugs in their pharmaceutical preparation and human plasma. The other methods are UV-spectrophotometric methods based on smart spectra manipulating to zero order spectrum of each drug. These methods are named response correlation (RC), a-centering and ratio derivative methods. RC and a-centering methods were dependent on the presence of an isosbestic point between the overlapped spectra of both drugs. While ratio derivative method based on manipulation of the ratio spectra of both drugs. The two drugs obey Beer-Lambert law over the concentration ranges of 3.0-30.0 μg/mL in the three spectrophotometric methods. Moreover, the greenness of the developed methods is assessed using suitable analytical Eco-Scale and Green Analytical Procedure Index.

Ultrasensitive TLC determination of montlukast and loratadine mixture in human plasma utilizing fluorescence detection at dual pH values: Toward attaining separate maximum fluorescence intensity

A novel selective and highly sensitive TLC densitometric method with reflectance/fluorescence detection was developed to separate and quantify montlukast (MONT) and loratadine (LOR). Separation of the studied drugs was performed on precoated silica gel TLC plates using chloroform-ethyl acetate (8 :2 v/v) as a mobile phase. MONT quantification was carried out by measuring emission using 400 nm optical filter after excitation at 340 nm. Enhancement of the week LOR fluorescence was performed through adequate spraying the chromatograms with 0.2 M perchloric acid leading to enhancing sensitivity by 17 folds compared to the reported HPTLC methods with absorbance detection. The scanner was set at 275 nm excitation wavelength and 400 nm optical filter. Detection of both drugs on the same plate separately at different pH conditions was utilized for the first time. Maximum fluorescence was achieved for each of them and this enhances detection sensitivity for both drugs. The linear regression analysis data of the studied drugs produced a good linear relationship with correlation coefficients of 0.996 for MONT and 0.998 for LOR over the concentration range of 6 - 150 ng/band for MONT and 15 - 120 ng/band for LOR. Limit of detection values were 1.7 and 4.5 ng /band for MONT and LOR respectively. The developed method enabled the detection of MONT and LOR in human plasma samples within linear concentrations ranged from 7 to 140 ng/ band and 16 to 50 ng/ band with detection limits of 1.9 and 4.8 ng/band for MONT and LOR respectively. The analytical performance of the proposed method was evaluated according to the International Council for Harmonization (ICH). The method was successfully applied for the analysis of the studied drugs in spiked human plasma and good recovery percentages were obtained indicating that there is no interference from plasma constituents. Therefore the method can be applied for in vivo analysis and pharmacokinetic study.

Development of LC-MS/MS method and application to bioequivalence study of a light sensitive drug montelukast

OBJECTIVE

The aim of the study was to develop a simple, highthroughput and sensitive LC-MS/MS method and apply to a bioequivalence study of montelukast, a light sensitive drug.

METHOD

The effects of organic modifiers in mobile phase, protein precipitation agent to plasma sample ratio, and light on montelukast stability in unprocessed and processed human plasma, were evaluated. Validation was conducted in accordance with European Medicines Agency Guideline on bioanalytical method validation.

RESULTS

No interference peak was observed when acetonitrile was used as an organic modifier. Acetonitrile to plasma ratio of 4:1 produced clean plasma sample. Approximately 3 % of cis isomer was detected in unprocessed plasma samples while 21 % of cis isomer was detected in processed plasma samples after exposing to fluorescent light for 24h. The standard calibration curve was linear over 3.00-1200.00 ng/mL. All method validation parameters were within the acceptance criteria.

CONCLUSION

The validated method was successfully applied to a bioequivalence study of two montelukast formulations involving 24 healthy Malaysian volunteers. The light stability of a light sensitive drug in unprocessed and processed human plasma samples should be studied prior to pharmacokinetic/bioequivalence studies. Measures could then be taken to protect the analyte in human plasma from light degradation.

A Review of Different Analytical Techniques for Fexofenadine Hydrochloride and Montelukast Sodium in Different Matrices

Fexofenadine hydrochloride is an antihistamine agent used for the treatment of allergic disorders like rhinitis. It is a second generation antihistamine. Montelukast sodium is an anti-asthmatic agent and leukotriene receptor antagonist used in the treatment of respiratory disorders. This article exemplifies the reported analytical methods like electrometric methods, ultraviolet spectroscopy, mass spectroscopy, thin layer chromatography, high performance liquid chromatography, high performance thin layer chromatography and tandem spectroscopy for determination of fexofenadine HCl and montelukast sodium in dosage form and in biological matrices. This review covers almost all the analytical methods for fexofenadine hydrochloride and montelukast sodium form 1968-2018 years. Complete analytical validation parameters reported are discussed in this review for both analytes. Among various analytical methods, HPLC and UV-visible spectrophotometry were found to be the most extensively used methods by the researchers.

Development and validation of RP-HPLC method with ultraviolet detection for estimation of montelukast in rabbit plasma: Application to preclinical pharmacokinetics

OBJECTIVE

To develop a liquid-liquid extraction based reverse phase liquid chromatography method for estimation of montelukast in rabbit plasma.

METHODS

Chromatographic separation was carried out using Phenomenex Luna C18 column (250 mm × 4.6 mm × 5 μm) with mobile phase composed of ammonium acetate buffer (20 Mm), pH 5.5 and acetonitrile in 20:80, v/v ratio. The analyte was monitored with UV detector at 345 nm. The developed method was validated with respect to linearity, accuracy, precision, specificity and stability.

RESULTS

The peak area ratio of montelukast (MKS) to that of internal standard was used for the quantification of samples. Calibration curves were linear in the concentration range of 20-2000 ng mL(-1). The LOD and LLOQ of present method were found out to be 10 ng mL(-1) and 20 ng mL(-1) respectively. The intra-day and inter-day %CV values for MKS were below 6.06% and 8.43%. Intra-day and inter-day accuracies were within 95.81% and 110.90%, respectively. Extraction recoveries of drug from rabbit plasma were >66.47%.

CONCLUSION

A simple, alternative, reproducible and sensitive HPLC-UV method was developed for MKS that can be used in preclinical pharmacokinetics.

Development and Validation of a Rapid RP-UPLC Method for the Simultaneous Estimation of Bambuterol Hydrochloride and Montelukast Sodium from Tablets

A rapid, simple, sensitive and selective analytical method was developed by using reverse phase ultra performance liquid chromatographic technique for the simultaneous estimation of bambuterol hydrochloride and montelukast sodium in combined tablet dosage form. The developed method is superior in technology to conventional high performance liquid chromatography with respect to speed, resolution, solvent consumption, time, and cost of analysis. Elution time for the separation was 6 min and ultra violet detection was carried out at 210 nm. Efficient separation was achieved on BEH C18 sub-2-μm Acquity UPLC column using 0.025% (v/v) trifluoro acetic acid in water and acetonitrile as organic solvent in a linear gradient program. Resolutions between bambuterol hydrochloride and montelukast sodium were found to be more than 31. The active pharmaceutical ingredient was extracted from tablet dosage from using a mixture of methanol, acetonitrile and water as diluent. The calibration graphs were linear for bambuterol hydrochloride and montelukast sodium in the range of 6.25-37.5 μg/ml. The percentage recoveries for bambuterol hydrochloride and montelukast sodium were found to be in the range of 99.1-100.0% and 98.0-101.6%, respectively. The test solution was found to be stable for 7 days when stored in the refrigerator between 2-8°. Developed UPLC method was validated as per International Conference on Harmonization specifications for method validation. This method can be successfully employed for simultaneous estimation of bambuterol hydrochloride and montelukast sodium in bulk drugs and formulations.

Simultaneous determination of montelukast as sparing therapy with some inhaled corticosteroids in plasma of asthmatic patients

Montelukast (MKST) is a leukotriene receptor antagonist that has been concomitantly used with inhaled corticosteroids (ICS) for its steroid-sparing effect in the long-term management of asthma. However, the simultaneous determination of MKST, when used as ICS tapering therapy, with ICS in human plasma has not yet been reported. A fast and efficient reversed phase monolith HPLC method was developed for simultaneous determination of MKST with some ICS in plasma of asthmatic patients. The separation was achieved on monolith reversed phase column by isocratic mode at a flow rate of 1.0 ml min(-1) using a mobile phase consisted of a mixture of acetonitrile and 10mM phosphate buffer adjusted to pH 3.5 (40:60, v/v) and detected at 240 nm. Betamethasone dipropionate (BDP) was used as the internal standard. All the studied ICS and MKST were efficiently separated within less than 6 min. The obtained linearity range for the developed HPLC method was 0.03-10 μg ml(-1) with correlation coefficients>0.9995 and the detection limits were 0.009-0.016 μg ml(-1) in plasma for all the studied drugs. The method was validated in agreement with the requirements of US-FDA guideline and was recommended for the target applications. The method is valuable for investigations concerned with the effective tapering of ICS therapy with MKST in patients with chronic asthma in clinical practice without loss of asthma control.

Development and Validation of a RP-HPLC Method for Estimation of Montelukast Sodium in Bulk and in Tablet Dosage Form

The present work describes a simple, precise and accurate HPLC method for estimation of montelukast sodium in bulk and in tablet dosage form. The separation was achieved by using octadecylsilane column (C18) and acetonitrile:1 mM sodium acetate adjusted to pH 6.3 with acetic acid in proportion of 90:10 v/v as mobile phase, at a flow rate of 1.5 ml/min. Detection was carried out at 285 nm. The retention time of montelukast sodium was found to be 3.4 min. The limit of detection was found 1.31 µg/ml and limit of quantification 3.97 µg/ml. The accuracy and reliability of the proposed method was ascertained by evaluating various validation parameters like linearity (1-100 µg/ml), precision, accuracy and specificity according to ICH guidelines. The proposed method provides an accurate and precise quality control tool for routine analysis of montelukast sodium in bulk and in tablet dosage form.

Method development and validation of montelukast in human plasma by HPLC coupled with ESI-MS/MS: application to a bioequivalence study

A simple, sensitive, and specific LC-ESIâMS/MS method for quantification of Montelukast (MO) in human plasma using Montelukast-d(6) (MOD6) as an internal standard (IS) is discussed here. Chromatographic separation was performed on YMC-pack pro C(18), 50 x 4.6 mm, S-3 Îm column with an isocratic mobile phase composed of 10mM ammonium formate (pH 4.0):acetonitrile (20:80 v/v), at a flow-rate of 0.8 mL min(â1). MO and MOD6 were detected with proton adducts at m/z 586.2â568.2 and 592.3â574.2 in multiple reaction monitoring (MRM) positive mode respectively. MO and MOD6 were extracted using acetonitrile as precipitating agent. The method was validated over a linear concentration range of 1.0â800.0 ng mL(â1) with correlation coefficient (r(2)) â 0.9996. The intraday precision and accuracy were within 1.91â7.10 and 98.32â99.17. The inter-day precision and accuracy were within 3.42â4.41% and 98.14â99.27% for MO. Both analytes were found to be stable throughout three freeze-thawing cycles, bench top, and autosampler stability studies. This method was utilized successfully for the analysis of plasma samples following oral administration of MO (5 mg) in 31 healthy Indian male human volunteers under fasting conditions.

A rapid and sensitive method for the quantitation of montelukast in sheep plasma using liquid chromatography/tandem mass spectrometry

A rapid LC-MS/MS method was developed and partially validated for the quantitation of montelukast in spiked sheep plasma. A total run time of 1.5 min was achieved using a short monolithic column and employing a rapid gradient. Sample preparation involved protein precipitation with twofold acetonitrile by volume during which a deuterated internal standard (montelukast D-6) was incorporated. The MRM transitions for montelukast and the deuterated internal standard were 586/422 and 592/427, respectively. A linear dynamic range of 0.25-500 ng/mL with a correlation coefficient of 0.9999 was achieved. Precision was below 5% at all levels except at the LOQ (0.36 ng/mL) which demonstrated an overall of R.S.D. of 8%. Post-column infusion experiments were performed with precipitated plasma matrix and showed minimal interference with the peaks of interest.

Complexation study of cinalukast and montelukast with cyclodextrines

A fluorimetric study on the spectral characteristics of two antileukotrienes, cinalukast and montelukast, has been performed. Ionization constants of both of them have been photometrically calculated. Cinalukast pK(a) in ethanol:water 50:50 (v/v) medium resulted to be 2.2+/-0.1. Because the spectral characteristics of montelukast are widely affected by the solvent nature, pK(a) was estimated in two different ethanol:water media, 70:30 (v/v) and 10:90 (v/v) and the values calculated were pK(a)=2.9+/-0.1, and pK(a1)=2.0+/-0.1 and pK(a2)=6.5+/-0.1, respectively. It has been proven that the fluorescence of both, cinalukast and montelukast, is significantly intensified in the presence of cyclodextrins (CyDs). The host-guest complexation processes between cinalukast and alpha-CyD or heptakis-(2,6-di-O-methyl)-beta-cyclodextrin (DIMEB) and between montelukast and DIMEB have been investigated by fluorescence spectroscopy. A 1:1 stoichiometric ratio was established for the three studied inclusion complexes. The changes produced on the fluorescence of cinalukast or montelukast, when they are included on the hydrophobic CyD cavity are used to calculate their association constants by a non-linear regression method. Semiempirical MO calculations using AM1 method were performed in order to characterize the studied inclusion complexes. A new method for cinalukast determination in human serum, based on the fluorescence of the complex cinalukast-DIMEB exhibiting limit of detection of 7.95 ng mL(-1) has been proposed with satisfactory results. Adequate recovery values between 95 and 103% were calculated at five different concentration levels.

Voltammetric determination of montelukast sodium in dosage forms and human plasma

The voltammetric behaviour of montelukast (MKST) was studied using cyclic voltammetry, direct current (DCt), differential pulse polarography (DPP) and alternating current (ACt) polarography. MKST exhibited well-defined cathodic waves over the range pH range 1-5. No anodic waves were produced over the same pH range. At pH 1, the analytical pH; the diffusion current constant (Id) was 2.2+/-0.01 microA l mmol-1. The current concentration plot was rectilinear over the range 2-20 microg ml-1 with correlation coefficient (n=10) of 0.9943. The lower limit of detection (S/N=2) was 0.2 microg ml-1 (3.41x10(-7) M). The wave has been characterised as being diffusion-controlled, although adsorption phenomenon played a limited role in the electrode reaction. The proposed method was successfully applied to the determination of MKST in commercial tablets, and results were in agreement with those given with a reference HPLC method. The method was further extended to the in vitro determination of the drug in spiked human plasma. The mean % recovery (n=5) was 101.38+/-3.85. The number of electrons transferred in the reduction process could be accomplished and a proposal of the electrode reaction was proposed.

Simultaneous determination of baicalin, rhein and berberine in rat plasma by column-switching high-performance liquid chromatography

A simple HPLC method using column-switching and ultraviolet detection was developed for the simultaneous determination of baicalin (BA), rhein (RH) and berberine (BE) in rat plasma. Plasma samples were injected directly onto a Capcell Pak MF C(8) column (150 mm x 4.6 mm i.d.) to remove protein and to be pre-separated by an isocratic elution using 50 mmol/L phosphate sodium (pH 6.85)-acetonitrile (10:1, v/v). After the drug-containing fractions were transferred to a Kromasil C(18) column (150 mm x 4.6 mm i.d.) by a valve switching step, the valve position was switched back and the main separation was performed by an isocratic elution using triethylamine adjusted 20 mmol/L phosphoric acid (pH 6.78)-acetonitrile (4:1, v/v). The flow rate was always 1.0 mL/min. The calibration curve showed excellent linear relationship (r>or=0.9997) over the concentration range of 0.4-7.9 microg/mL for baicalin, 0.2-7.8 microg/mL for rhein and 0.4-7.7 microg/mL for berberine in rat plasma. The intra- and inter-day assay precisions (R.S.D.) of three analytes were in the range of 0.34-4.3% and the accuracies were between 98.0% and 102.4%. Their recoveries were all greater than 95%. The method was successfully applied to the multi-constituents plasma concentration-time curve study after oral administration of a traditional Chinese medicine prescription Xiexin-Tang in rats.

Restricted access materials and large particle supports for on-line sample preparation: an attractive approach for biological fluids analysis

An analytical process generally involves four main steps: (1) sample preparation; (2) analytical separation; (3) detection; and (4) data handling. In the bioanalytical field, sample preparation is often considered as the time-limiting step. Indeed, the extraction techniques commonly used for biological matrices such as liquid-liquid extraction (LLE) and solid-phase extraction (SPE) are achieved in the off-line mode. In order to perform a high throughput analysis, efforts have been engaged in developing a faster sample purification process. Among different strategies, the introduction of special extraction sorbents, such as the restricted access media (RAM) and large particle supports (LPS), allowing the direct and repetitive injection of complex biological matrices, represents a very attractive approach. Integrated in a liquid chromatography (LC) system, these extraction supports lead to the automation, simplification and speeding up of the sample preparation process. In this paper, RAM and LPS are reviewed and particular attention is given to commercially available supports. Applications of these extraction supports, are presented in single column and column-switching configurations, for the direct analysis of compounds in various biological fluids.

Simultaneous determination of montelukast and loratadine by HPLC and derivative spectrophotometric methods

In this study, high performance liquid chromatography (HPLC) and second derivative spectrophotometry have been used and described for the simultaneous determination of montelukast and loratadine in pharmaceutical formulations. HPLC separation was achieved with a Symmetry C18 column and sodium phosphate buffer (pH adjusted to 3.7): acetonitrile (20:80, v/v) as eluent, at a flow rate of 1.0 ml/min. UV detection was performed at 225 nm. The LC method is simple, rapid, selective and stability indicating for the determination of montelukast. 5-Methyl 2-nitrophenol was used as internal standard for the purpose of quantification of both the drugs in HPLC. In the second-order derivative spectrophotometry, for the determination of loratadine the zero-crossing technique was applied at 276.1 nm, but for montelukast peak amplitude at 359.7 nm (tangent method) was used. Both methods were fully validated and a comparison was made for assay determination of selected drugs in formulations. The results confirm that the methods are highly suitable for its intended purpose.

Expedient liquid chromatographic method with fluorescence detection for montelukast sodium in micro-samples of plasma

This study describes an expedient assay for the analysis of the asthma medication, montelukast sodium (Singulair, MK-0476), in human plasma samples. After a simple extraction of the plasma, the drug and internal standard, quinine bisulfate, were measured by HPLC. The chromatographic system consisted of a single pump, a refrigerated autosampler, a C8 4-microm particle size radial compression cartridge at 40 degrees C and a fluorescence detector with the excitation and emission wavelengths set at 350 and 400 nm, respectively. The mobile phase which was delivered at 1.0 ml/min, was prepared by adding 200 ml of 0.025 M sodium acetate, pH adjusted to 4.0 with acetic acid, to 800 ml of acetonitrile, with 50 microl triethylamine. With a run time of only 10 min per sample, this assay had an overall recovery of >97% with a detection limit of 1 ng/ml. The inter- and intra-run relative standard deviations at 0.05, 0.2 and 1.0 microg/ml were all <9.2%, while the analytical recovery at the same concentrations were within 7.7% of the amount added.