Novel sensing probe using Terbium-sensitized luminescence and 8-hydroxyquinoline for determination of prucalopride succinate: green assessment with Complex-GAPI and analytical Eco-Scale.

A highly sensitive spectrofluorimetric method is developed for the determination of prucalopride succinate (PRU). The method depends on lanthanide-sensitized luminescence due to complex formation between the drug and terbium chloride (Tb+3) which is enhanced by the addition of 8 hydroxyquinoline (8HQ) and phosphate buffer (0.02 M, pH 3.2). The calibration curve was constructed over the linear range 10-300 ng/mL after excitation at 226 nm and measuring the emission of the ternary complex at 544 nm. The method was validated according to ICH Q2 (R1) guidelines and showed a good recovery ± RSD of 100.41% ± 1.26, the limits of detection and quantitation were found to be 2.81 and 8.53 ng/mL, respectively. The proposed method was successfully applied for the determination of the drug marketed tablet dosage form and the results were in good agreement with the reference method. Also, the method greenness was evaluated according to Complex-GAPI and analytical Eco-Scale.

The concept of Relative Absorptivity Distribution for enhancing disbanding power of spectrophotometric technique to resolve co-formulated tablets: A tool for purity index and uniformity assessment.

Resolving the spectral bands of the drugs into their discrete constituents is critical for an effective mathematical spectrophotometric method. The spectral resolution is ordinarily affected by the required application. In the current work an innovative, simple and green Relative Absorptivity Distribution (RAD) concept was established for the successful assay and assessing of content uniformity and purity index of tablet co-formulation which is recommended for lowering the blood glucose level and is comprised of Cangliflozin (CGF) and Metformin CGF and MTF. From the spectrophotometric perspective, the investigation of this combination is challenging as the composition of the tablets is CGF:MTF (1:17), where CGF is not only the minor analyte but also the one of lower absorptivity. The RAD concept is based on the production of master Resolving Spectra (RS). Within the RAD concept and according to the manipulation used for the generation of the RS, three different univariate mathematic methods via spectrophotometer software were developed. The proposed methods are characterized by the ability of extracting the raw spectra of each investigated analyte separately, consequently, enabling each analyte to be determined at its λmax without the contribution of the other. The proposed methods had analyzed CGF in the range 1.0-30.0 µg/mL and MTF within the range 1.0-20.0 µg/mL. The guidelines of the ICH were performed for the complete validation of all methods and the results confirmed satisfactory accuracy, precision and selectivity. The accomplished results together with the simplicity and low-cost of all methods suggested their suitability for the routine quality control analysis of bulk materials, assay of the pharmaceutical formulations and evaluating the content uniformity. Statistical comparison of the results with those of reported HPLC method showed good agreement. In addition, the environmental impact of the proposed methods was assessed by utilizing the National Environmental Methods Index (NEMI), the Analytical Eco-Scale and the Green Analytical Procedure Index (GAPI) where the three tools confirmed the environmentally friendly nature of all proposed methods.

Novel LC-MS/MS method for analysis of metformin and canagliflozin in human plasma: application to a pharmacokinetic study.

Highly sensitive and selective liquid chromatography/tandem mass spectrometry (LC-MS/MS) method was developed and validated for the simultaneous estimation of the recently approved oral hypoglycemic mixture; metformin (MET) and canagliflozin (CFZ) in human plasma using propranolol HCl (PPL) and tadalafil (TDF) as internal standards (IS), respectively. Analytes were extracted using protein precipitation induced by acetonitrile then liquid-liquid extraction was performed using ethyl acetate. Reversed phase HPLC was carried out using C18 analytical column (50 mm × 4.6 mm i.d., 5 µm) with a simple isocratic mobile phase composed of 0.1% formic acid and acetonitrile (60:40, v/v). Detection was performed on a triple quadrupole mass spectrometer employing electrospray ionization technique, operating in multiple reaction monitoring (MRM), with the transitions of m/z 130.2 → 60.1, m/z 462.3 → 191.0, m/z 260.2 → 183.0 and m/z 390.2 → 268.2 for MET, CFZ, PPL and TDF, respectively, in the positive ion mode. The analysis was carried out within 5 min over a linear concentration range of 50-5000 ng/mL for MET and 10-1000 ng/mL for CFZ. The method was validated in accordance with the FDA guidelines for bioanalytical method. All obtained recoveries were higher than 90.0% while the accuracy was in the range of 88.14-113.05% and the relative standard deviation was below 10.0% for all investigated drugs by the proposed method. The achieved promising results has allowed for the successful application of the developed LC-MS/MS method to a pharmacokinetic study of the target drugs after their oral administration to Egyptian healthy volunteers. The pharmacokinetic study was accomplished after the agreement of the ethics committee.

Novel univariate spectrophotometric determination of the recently released solid dosage form comprising dapagliflozin and saxagliptin via factorized response spectra: Assessment of the average content and dosage unit uniformity of tablets.

Dapagliflozin (DPF) and saxagliptin (SXG) are currently co-formulated in a tablet dosage form which is prescribed to improve glycemic control. The absorption spectra of DPF and SXG were highly overlapped which completely hindered their simultaneous estimation at their λmax 224 nm and 209 nm, respectively. Thus, in this work three smart and simple univariate spectrophotometric methods were originally established and validated for the first time in order to quantitatively estimate DPF and SXG in bulk forms and in combined pharmaceutical formulation without the requirement for any initial separation or treatment. These methods are; factorized zero order method (FZM), factorized derivative method (FDM) and factorized ratio difference method (FRM). These methods were capable of determining DPF and SXG over the range of 2.5-50.0 µg/mL and 2.5-60.0 µg/mL, respectively. All the developed methods are based on a novel and unique approach for the spectral recovery of unresolved spectra named; factorized response spectrum (FRS). The exclusivity of the FRS originates from its ability to completely resolve the cited drugs in the mixture and retrieve their original spectra. Selectivity of all proposed methods was assessed by comparing the obtained results of the mixture analysis with those of the pure powdered drugs. Validation of the newly developed methods was applied as recommended by the ICH demonstrating acceptable accuracy and precision. In general, these methods could be effectively employed for the routine quality control investigation of bulk materials and available market formulations.

Novel contribution to the simultaneous monitoring of pramipexole dihydrochloride monohydrate and levodopa as co-administered drugs in human plasma utilizing UPLC-MS/MS.

An efficient, selective, sensitive, and rapid ultra-performance liquid chromatography tandem mass spectrometry method was established and validated for the quantification of pramipexole dihydrochloride monohydrate and levodopa simultaneously in human plasma with the aid of diphenhydramine as an internal standard. A simple protein precipitation technique with HPLC grade acetonitrile was efficiently utilized for the cleanup of plasma. The analysis was performed using a Hypersil gold 50 mm × 2.1 mm (1.9 µm) column and a mobile phase of 0.2% formic acid and methanol (90: 10 v/v). The triple-quadrupole mass spectrometer equipped with an electrospray source operated in the positive mode was set up in the selective reaction monitoring mode (SRM) to detect the ion transitions m/z 212.15 →153.01, m/z 198.10→ 135.16, and m/z 255.75 → 166.16 for pramipexole dihydrochloride monohydrate, levodopa, and diphenhydramine, respectively. The method was thoroughly validated according to FDA guidelines and proved to be linear, accurate, and precise over the range 100-4000 pg/mL for pramipexole dihydrochloride monohydrate and 60-4000 ng/mL for levodopa. The proposed method was effectively applied for monitoring both drugs in plasma samples of healthy volunteers.

Liquid chromatography-tandem MS/MS method for simultaneous quantification of paracetamol, chlorzoxazone and aceclofenac in human plasma: An application to a clinical pharmacokinetic study.

A facile, fast and specific method based on liquid chromatography-tandem mass spectrometry (LC-MS/MS) for the simultaneous quantitation of paracetamol, chlorzoxazone and aceclofenac in human plasma was developed and validated. Sample preparation was achieved by liquid-liquid extraction. The analysis was performed on a reversed-phase C18 HPLC column (5 µm, 4.6 × 50 mm) using acetonitrile-10 mM ammonium formate pH 3.0 (65:35, v/v) as the mobile phase where atrovastatin was used as an internal standard. A very small injection volume (3 µL) was applied and the run time was 2.0 min. The detection was carried out by electrospray positive and negative ionization mass spectrometry in the multiple-reaction monitoring mode. The developed method was capable of determining the analytes over the concentration ranges of 0.03-30.0, 0.015-15.00 and 0.15-15.00 µg/mL for paracetamol, chlorzoxazone and aceclofenac, respectively. Intraday and interday precisions (as coefficient of variation) were found to be ≤12.3% with an accuracy (as relative error) of ±5.0%. The method was successfully applied to a pharmacokinetic study of the three analytes after being orally administered to six healthy volunteers.

Different mathematical processing of absorption, ratio and derivative spectra for quantification of mixtures containing minor component: An application to the analysis of the recently co-formulated antidiabetic drugs; canagliflozin and metformin.

In the presented work several spectrophotometric methods were performed for the quantification of canagliflozin (CGZ) and metformin hydrochloride (MTF) simultaneously in their binary mixture. Two of these methods; response correlation (RC) and advanced balance point-spectrum subtraction (ABP-SS) were developed and introduced for the first time in this work, where the latter method (ABP-SS) was performed on both the zero order and the first derivative spectra of the drugs. Besides, two recently established methods; advanced amplitude modulation (AAM) and advanced absorbance subtraction (AAS) were also accomplished. All the proposed methods were validated in accordance to the ICH guidelines, where all methods were proved to be accurate and precise. Additionally, the linearity range, limit of detection and limit of quantification were determined and the selectivity was examined through the analysis of laboratory prepared mixtures and the combined dosage form of the drugs. The proposed methods were capable of determining the two drugs in the ratio present in the pharmaceutical formulation CGZ:MTF (1:17) without the requirement of any preliminary separation, further dilution or standard spiking. The results obtained by the proposed methods were in compliance with the reported chromatographic method when compared statistically, proving the absence of any significant difference in accuracy and precision between the proposed and reported methods.

Novel pure component contribution, mean centering of ratio spectra and factor based algorithms for simultaneous resolution and quantification of overlapped spectral signals: An application to recently co-formulated tablets of chlorzoxazone, aceclofenac and paracetamol.

In this work, resolution and quantitation of spectral signals are achieved by several univariate and multivariate techniques. The novel pure component contribution algorithm (PCCA) along with mean centering of ratio spectra (MCR) and the factor based partial least squares (PLS) algorithms were developed for simultaneous determination of chlorzoxazone (CXZ), aceclofenac (ACF) and paracetamol (PAR) in their pure form and recently co-formulated tablets. The PCCA method allows the determination of each drug at its λmax. While, the mean centered values at 230, 302 and 253nm, were used for quantification of CXZ, ACF and PAR, respectively, by MCR method. Partial least-squares (PLS) algorithm was applied as a multivariate calibration method. The three methods were successfully applied for determination of CXZ, ACF and PAR in pure form and tablets. Good linear relationships were obtained in the ranges of 2-50, 2-40 and 2-30µgmL(-1) for CXZ, ACF and PAR, in order, by both PCCA and MCR, while the PLS model was built for the three compounds each in the range of 2-10µgmL(-1). The results obtained from the proposed methods were statistically compared with a reported one. PCCA and MCR methods were validated according to ICH guidelines, while PLS method was validated by both cross validation and an independent data set. They are found suitable for the determination of the studied drugs in bulk powder and tablets.

Capillary electrophoretic determination of antimigraine formulations containing caffeine, ergotamine, paracetamol and domperidone or metoclopramide.

A novel, fast, sensitive and specific technique using capillary electrophoresis coupled to a diode array detector has been developed for the separation and simultaneous determination of two antimigraine mixtures in tablet formulation. The two combinations are ergotamine tartrate (ERG), caffeine (CAF) and paracetamol (PAR) with either domperidone (DOM), combination (I) or metoclopramide (MET), combination (II). The proposed method utilized a fused silica capillary (55 cm × 75 µm i.d.) and background electrolyte composed of phosphate buffer (25 mM, pH 9.8). The separation was achieved at 20 KV applied voltage and at 25°C. The described method was linear over the range of 1-80 and 2-100 µg/mL for CAF and MET, respectively, and 1-80 µg/mL for DOM, ERG and PAR. Intra-day and inter-day relative standard deviation (n = 5) was ≤1.10%. The limits of detection of CAF and PAR were 0.20 and 0.10 µg/mL, respectively, and 0.50 µg/mL for MET, DOM and ERG. Other aspects of analytical validation were also evaluated. The proposed method was successfully applied to the analysis of the two combinations in their tablets. Therefore, the proposed method is suitable for the routine control of these ingredients in multicomponent dosage forms.