Integrated spectroscopic approaches for the facile one pot quantification of olanzapine in pharmaceutical formulation and spiked human plasma.

In this work, the xanthene dye, erythrosine B, was employed as a probe for the determination of olanzapine using two fast and highly simple analytical approaches. The assay was based on the formation of a binary complex between the drug and erythrosine B in a slightly acidic aqueous buffered solution. In the first method, the absorbance of the formed product was monitored at 558 nm. The reaction stoichiometry was investigated, and the stability constant of the formed complex was estimated. The linear range of the method that obeyed Beer's law was in the concentration range of 0.6-8.0 µg/ml. The calculated detection and quantitation limits were 0.2 and 0.6 µg/mL. Upon adding the drug solution to erythrosine B, the native fluorescence of the dye was quenched and monitored at 550 nm after excitation at 528 nm. Thus, the fluorescence quenching was utilized as the quantitative signal in the spectrofluorimetric approach. The extent of quenching in the fluorescence intensity was rectilinear with the drug concentration in a range of 0.1-2.5 µg/ml with a detection limit of 0.032 µg/ml. Both approaches were analytically validated based on the guiding rules of the ICH with acceptable results, and were utilized efficiently in the analysis of olanzapine in commercial tablets containing the cited drug. In addition, owing to its high sensitivity and selectivity, the spectrofluorimetric method was applied for drug analysis in spiked human plasma with satisfactory % recoveries. Finally, the greenness of the methods was confirmed using eco-score scale and Analytical Green Evaluation metrics.

Enhancing simultaneous determination of some angiotensin II receptor antagonists and amlodipine in plasma using HPTLC with fluorescence densitometry: Independent fluorescence detection of the co-administrative drugs in the mixture across various pH conditions.

A novel and highly sensitive high-performance thin-layer chromatographic (HPTLC) method was developed and validated to quantify a combination of five pharmaceutical mixtures spiked to human plasma. The compounds comprised Amlodipine (AML) along with five angiotensin II receptor antagonist drugs (AIIRAs), namely Olmesartan (OLM), Telmisartan (TLM), Candesartan (CAN), Losartan (LOS), and Irbesartan (IRB). HPTLC was performed on silica gel 60 F254 plates using a mobile phase of Toluene: ethyl acetate: methanol: acetone: acetic acid (6:1.5:1:0.5:1, v/v/v/v/v). In a pioneering move, a reflectance/fluorescence detection mode was employed to identify two concurrently administered drugs at different pH levels for the first time. This method utilized the same chromatographic system, incorporating a specific measurement for AML at a neutral medium to achieve its maximum fluorescence at a 360 nm excitation wavelength, and measuring emission using a 540 nm optical filter. The process involved obtaining a very low fluorescence response from AIIRA. Subsequently, to enhance AIIRA's fluorescence, the plate was sprayed with perchloric acid to transition to a strong acidic medium, ultimately attaining the maximum fluorescence of AIIRA using various excitation wavelengths and a 400 nm emission filter. Through this strategic process, we could optimize the fluorescence signals of both drugs, thereby elevating the sensitivity of detection for this drug combination. AML demonstrated a linear range of 18-300 ng/band, while AIIRAs drugs exhibited a linear range of 6-150 ng/band. The method satisfied the International Conference on Harmonization (ICH) criteria for recovery, precision, repeatability, and robustness, showcasing exceptional sensitivity. The approach was successfully applied to quantify AML and AIIRAs drugs in both bulk drug and plasma samples, achieving high recovery percentages and minimal standard deviations.

Diaryl pyrrolone fluorescent probing strategy for Mirabegron determination through condensation with ninhydrin and phenylacetaldehyde: Application to dosage forms, human urine and plasma.

Mirabegron (MRB) is a ß3-adrenoceptor agonist used for managing overactive bladder syndrome. A cost-effective, environmentally friendly, and highly sensitive spectrofluorimetric method was suggested to serve the purpose of quantifying MRB in its pure state, pharmaceutical tablets, spiked human plasma and urine, and testing content uniformity. In the present study, ninhydrin and phenylacetaldehyde react with the amino group moiety of MRB in Teorell-Stenhagen buffer (pH 7.5) to generate a strongly fluorescent diaryl pyrrolone compound that emits fluorescence at a wavelength of 477 nm upon excitation at 385 nm. The obtained calibration curve showed a linear relationship with a high correlation coefficient (r = 0.9997) in the concentration range of 0.25 to 5.0 µg mL-1. Limits of detection (LOD) and quantitation (LOQ) were 0.082 and 0.248 µg mL-1 respectively. The procedure was verified in accordance with the ICH guidelines. The suggested approach could be utilized for the selective analysis of MRB in its pharmaceuticals, either containing a single drug or co-formulated with solifenacin succinate. The greenness of the suggested method was confirmed using different green analytical metrics.

Evaluation of the on-off fluorescence method for facile measurement of vilazodone in pharmaceutical dosage form; Application to content uniformity testing and greenness evaluation.

Vilazodone is a recently approved antidepressant medicine used for treating major depressive disorder. A simple, extremely sensitive, accurate and green spectrofluorimetric method was constructed for its determination through formation of ion-pair complex with erythrosine B. The formation of ion-pair complex lowers the dye's native fluorescence emission measured at 552 nm (λ ex = 530 nm). In terms of analysis, the system's parameters for producing the vilazodone-erythrosine B complex have been optimized. The reaction was carried out in Teorell-Stenhagen buffering solution (pH 4.6). The fluorescence emission intensity of the dye decreased linearly in the range of 20 - 600 ng mL-1 and the correlation coefficient was 0.9999. The quantitation and detection limit values were 18.5 and 6.1 ng mL-1, respectively. The proposed strategy has been validated according to the ICH criteria. The proposed technique was thoroughly employed for evaluating vilazodone in raw material and pharmaceutical tablet dosage form. Furthermore, it was also successfully used for content uniformity testing. Lastly, using four advanced tools namely the Eco-Scale, the National Environmental Method Index (NEMI), the Green Analytical Procedure Index (GAPI), and the Analytical Greenness metric approach (AGREE), the greenness of the established technique was evaluated.

Simultaneous measurement of duloxetine hydrochloride and avanafil at dual-wavelength using novel ecologically friendly TLC-densitometric method: application to synthetic mixture and spiked human plasma with evaluation of greenness and blueness.

The simultaneous assay of duloxetine hydrochloride (DLX) and avanafil (AVN) in their pure forms, synthetic mixtures, and spiked human plasma was achieved using a novel, eco-friendly, sensitive, and specific HPTLC methodology that have been established and validated. Measuring the levels of co-administered antidepressants and sexual stimulants in biological fluids is an important step for individuals with depression and sexual problems. Separation was performed successfully using pre-coated silica gel 60-F254 as a stationary phase and a mobile phase composed of methanol, acetone, and 33% ammonia (8:2:0.05, v/v/v). Compact bands were produced by the optimized mobile phase that was chosen for development (Rf values were 0.23 and 0.75 for DLX and AVN, individually) after dual-wavelength detection for DLX and AVN at 232 and 253 nm, respectively. The results of polynomial regression analysis were exceptional (r = 0.9999 for both medicines) over concentration ranges of 5-800 and 10-800ng/spot for DLX and AVN, respectively. The quantitation limits were 4.69 and 9.53 ng/spot (0.31 and 0.94 µg/mL), whereas the detection limits were 1.55 and 3.15 ng/spot (0.63 and 1.91 µg/mL), for DLX and AVN, respectively. The International Council for Harmonization (ICH) criteria served as the basis for validating the established approach. Moreover, the proposed technique was evaluated in terms of greenness using four contemporary ecological metrics: The Analytical Greenness software (AGREE), the Green Analytical Procedure Index (GAPI), Eco-Scale, and the National Environmental Method Index (NEMI). Additionally, the Blue Applicability Grade Index (BAGI), a newly developed tool for evaluating the practicality (blueness) of procedures, was taken into consideration when evaluating the sustainability levels of the established approach.

Integrated resonance Rayleigh scattering approach utilizing Box-Behnken experimental design for the facile quantification of prucalopride in pharmaceutical tablets and human urine with sustainability assessment.

Prucalopride (PCP) is one of the recent drugs used for the regulation of gastrointestinal tract motility and the treatment of constipation. A new, highly sensitive and fast resonance Rayleigh scattering (RRS) approach was suggested for PCP determination. The approach was based on its reaction of PCP with eosin Y in buffered medium (pH 3.5) to form an ion pair association complex which had a significant enhancement in RRS compared to that of eosin Y or PCP alone. The enhancement of RRS intensity had straight correlation to PCP concentration ranging from 150 to 2000 ng mL-1 with 38 ng mL-1 as LOD and 125 ng mL-1 as LOQ. The measurements were done at a wavelength of 365 nm that provided the maximum sensitivity. All the experimental parameters were studied carefully and optimized via Box-Behnken experimental design. The International Council for Harmonization (ICH) guidelines were employed to validate the suggested method and the obtained results proved the appropriate method performance. The method was efficiently utilized to determine PCP in pure form, pharmaceutical tablets and spiked urine samples with no interferences from the surrounding matrices. Furthermore, the greenness of the suggested procedure was confirmed using different green metric approaches.

A facile on-off fluorescence approach for fluvoxamine determination in pharmaceutical tablets; application to content uniformity testing.

A green-complied spectrofluorimetric approach for quantification of the antidepressant, fluvoxamine, has been established. The method that has been suggested relies on the development of an association complex between fluvoxamine and erythrosine B in an acetate buffer solution. After being excited at 530 nm, the quenching in erythrosine B's native fluorescence caused by complex formation with fluvoxamine was detected at a wavelength of 552 nm. The values of fluorescence quenching at the most optimal reaction conditions were rectilinear at the concentration range of 0.2-2.0 µg mL-1, with a good correlation coefficient (r = 0.9998). The detection limit for the method was 0.03 µg mL-1 while the quantitation limit was 0.09 µg mL-1. The suggested approach has been validated according to the ICH. The established approach was effectively used to determine the drug under study in its dosage form with an average percent recovery of 98.92 ± 0.87 (n = 5), with no effect caused by the existing excipients. The proposed approach was also successfully used for the content uniformity test.

Determination of antihistaminic drugs alcaftadine and olopatadine hydrochloride via ion-pairing with eosin Y as a spectrofluorimetric and spectrophotometric probe: application to dosage forms.

Four sensitive and fast analytical approaches relied on ion pairing with eosin Y were built up and evaluated using spectroscopy for determination of Alcaftadine and Olopatadine hydrochloride with high sensitivity and selectivity. Two spectrofluorimetric techniques were employed to observe the quenching effect of Alcaftadine or Olopatadine hydrochloride on the intrinsic fluorescence of eosin Y in a 0.1 M acetate buffer solution at pH 3.8 and 3.3 for Alcaftadine and Olopatadine hydrochloride, respectively. Those methods are considered the first spectrofluorimetric methods for Alcaftadine and Olopatadine hydrochloride assay. The fluorescence quenching effect was linear with concentration ranging from 150 to 2000 and 200 to 2000 ng mL-1 for Alcaftadine and Olopatadine hydrochloride, respectively. In the two spectrophotometric techniques, the absorbance of the produced ion-pair was monitored at 548 and 547 nm in aqueous buffered solution at pH 3.8 and 3.3 for Alcaftadine and Olopatadine hydrochloride, respectively. Beer's law was obeyed in the concentrations range of 0.8-8.0 and 1.0-10.0 µg mL-1. The four techniques were evaluated in accordance with ICH requirements and were effectively used to analyze dosage forms with a high percent recovery.

An eco-friendly one-pot spectrofluorimetric approach for the facile determination of overactive bladder drug, tolterodine: Application to dosage forms and biological fluids.

Tolterodine tartrate (TTD) was the first antimuscarinic medication developed exclusively for the treatment of overactive bladder syndrome and was approved by the FDA in 1998. As a result of the drug's extensive utilization within the local community following its authorization, there is a pressing need to develop and validate a spectrofluorometric method that is economically efficient, easily reproducible, environmentally sustainable, and possesses high sensitivity. The developed approach relies on enhancing the fluorescence intensity of TTD to reach a level 720 % higher than its initial value, achieved through the application of an aqueous sodium dodecyl sulfate (SDS) solution. A strong correlation was observed with a correlation coefficient of 0.9998 between the concentration of TTD and the fluorescence intensity within the range of 25.0-500.0 ng mL-1. This approach could be employed to quantify TTD in its pure form and to examine pharmaceutical tablets for the purposes of verifying uniform content. Additionally, it was utilized for the evaluation of TTD concentrations in spiked human plasma.

Development of a green synchronous spectrofluorimetric technique for simultaneous determination of Montelukast sodium and Bilastine in pharmaceutical formulations.

For the treatment of rhinitis and asthma, a combination of Montelukast sodium and Bilastine has just been approved. Based on the first derivative of synchronous fluorescence, the current work developed a green, highly accurate, sensitive, and selective spectroscopic approach for estimating Montelukast sodium and Bilastine in pharmaceutical dosage form without previous separation. The selected technique focuses on measuring the synchronized fluorescence of the studied medications at a fixed wavelength range (Δλ) = 110 nm, and using the amplitude of the first derivative's peak at 381 and 324 nm, for quantitative estimation of Montelukast sodium and Bilastine, respectively. The impacts of different factors on the referred drugs' synchronized fluorescence intensity were investigated and adjusted. The calibration plots for were found to be linear over concentration ranges of 50-2000 ng mL-1 for Montelukast sodium and 50-1000 ng mL-1 for Bilastine. Montelukast sodium and Bilastine have LODs of 16.5 and 10.9 ng mL-1, respectively. In addition, LOQs were: 49.9 and 33.0 ng mL-1, for both drugs, respectively. The developed method was successfully employed to quantify the two drugs in synthetic tablets mixture and in laboratory prepared mixtures containing varied Montelukast and Bilastine ratios. To compare the results with the published analytical approach, a variance ratio F-test and a student t-test were used, which revealed no significant differences.

Novel spectrofluorometric approach for assessing vilazodone by blocking photoinduced electron transfer: analytical performance, and greenness-blueness evaluation.

In this paper, vilazodone (VLD), a serotonin modulator prescribed for major depressive disorder, was investigated using a rapid, highly sensitive, and eco-friendly spectrofluorometric approach. The native fluorescence of VLD, originating from its indole moiety, exhibited an emission peak at 486 nm upon excitation at 241 nm. However, the presence of a piperazinyl nitrogen atom in the VLD structure, acting as an electron donor, significantly diminished the fluorescence intensity through photoinduced electron transfer (PET) to the indole ring. However, by protonating this nitrogen atom using 0.02 M Teorell-Stenhagen buffer (pH 3.5), inhibition of the PET process effectively blocked electron transfer, restoring the fluorescent properties of the drug. Further, an enhancement in the fluorescence was achieved by employing methanol as the solvent, resulting in a 1.5-fold increase. The combined use of PET blockage and methanol enabled the detection of VLD at levels as low as 0.78 ng mL-1. Calibration analysis demonstrated linearity within the range 5-400 ng mL-1, exhibiting a correlation coefficient of 0.9998 and a limit of quantification of 2.37 ng mL-1. The method obeyed the requirements of International Council on Harmonization (ICH). The proposed approach was applied for the accurate measurement of VLD in pharmaceutical tablets, content uniformity testing based on USP requirements, and determining VLD concentration in spiked human plasma. Moreover, the environmental impact, in addition to practical effectiveness, of the proposed approach was evaluated using different metrics.

The first spectrofluorimetric protocol for sensitive quantitative analysis of bromocriptine in its pure and pharmaceutical forms: evaluation of the greenness of the method.

Bromocriptine mesylate, a dopamine D2 receptor agonist, has been quantitatively determined using a sensitive, precise, quick, and affordable spectrofluorimetric method. The proposed method relies on the estimation of bromocriptine native fluorescence after the optimization of different factors to improve its inherently weak fluorescence through the use of a sodium dodecyl sulphate micellar system (2% w/v). Following excitation at 238 nm, the enhanced fluorescence intensity of bromocriptine was determined at 418 nm. As compared to its native fluorescence, the bromocriptine fluorescence intensity has been greatly enhanced by about 15 fold by employing the micellar system. The plot of intensity of fluorescence versus bromocriptine concentration was linear in the range of 50-600 ng mL-1. The method was found to have a high sensitivity, as indicated by the low limit of detection and limit of quantitation values (14.57 and 44.16 ng mL-1 respectively). Without the interference of any excipient, this method was effectively employed to quantify bromocriptine in its pharmaceutical dosage form.

Spectrofluorimetric Protocol for Estimation of Commonly Used Antispasmodic Drotaverine. Fluorescence Quenching Study.

A fast, simple, accurate, precise, and cheap fluorimetric protocol has been proposed for analysis of a phosphodiesterase-IV inhibitor, namely drotaverine hydrochloride. Fluorimetric protocol is based on estimating the decrease in the eosin Y fluorescence intensity by quantitative addition of drotaverine at pH 3.1 (acetate buffer). An ion pair complex is formed, which leads to quenching in the fluorescence intensity of the dye without need of prior extraction at 534 nm (λex. 339 nm). Different reaction perimeters which influence the production of complex (ion pair between drotaverine and eosin) were deeply investigated and optimized. The developed fluorimetric protocol is capable for quantitative estimation of drotaverine in linear range of 0.4 to 2.5 µg mL-1. After method validation in respect to ICH guidelines, it was applied to determine drotaverine in its commercial preparation. By comparing with other reported method, the developed and validated fluorimetric protocol is capable for estimation of drotaverine in commercial preparation with good accuracy and excellent precision.

Utility of dansyl chloride for the establishment of a sensitive spectrofluorimetric approach for estimating midodrine hydrochloride: application to content uniformity testing.

A new, straightforward spectrofluorimetric approach with high sensitivity was established for determining midodrine hydrochloride based on derivatizing this drug through its reaction with 5-(dimethylamino)naphthalene-1-sulfonyl chloride (dansyl chloride). The highly fluorescent product was extracted with methylene chloride, and then its emission was measured at 532 nm after excitation at 339 nm. The reaction was conducted in aqueous medium containing 0.1 M borate buffer (pH 8.2). The results showed that the proposed method is sensitive with high linearity in the range from 0.1 to 3 µg mL-1. The lower limits of detection and quantitation were 29 and 88 ng mL-1, respectively. Furthermore, the proposed approach was analytically assessed by applying the ICH guidelines. The suggested approach was effectively utilized for the estimation of the medicine in its marketable tablet formulations with excellent recovery and without any interfering effect from excipients. Moreover, the presented approach was utilized to test the content uniformity of commercial tablets following the USP guidelines.

Sensitive spectrofluorimetric determination of the prokinetic drug prucalopride succinate based on supramolecular aggregation approach with evaluation of method greenness: application to content uniformity test.

The prokinetic drug, prucalopride (PCP) succinate, was determined using a new spectrofluorimetric approach with a highly sensitive, rapid, and simple procedure. The method exploited the enhancement of the inherent native fluorescence of PCP by micellar aggregation with sodium lauryl sulfate (SLS) as an anionic surfactant. Different factors that could affect the fluorescence intensity were carefully studied in order to achieve the maximal fluorescence signal. Measurement of the enhanced fluorescence was done at 354 nm after the excitation at 276 nm. The fluorescence intensity-concentration plot was rectilinear in the concentration range of 50-600 ng/ml with detection and quantitation limits of 13.9 and 42.1 ng/ml, respectively. The method underwent validation according to the International Council for Harmonisation criteria in order to assess its analytical performance, and promising results were achieved that proved the validity and reliability of the method. Furthermore, the method was employed effectively for the analysis of the cited drug in commercial pharmaceutical tablets.

Mathematical processing of absorption as green smart spectrophotometric methods for concurrent assay of hepatitis C antiviral drugs, Sofosbuvir and Simeprevir: application to combined pharmaceutical dosage forms and evaluation of the method greenness.

The present work was developed to create three rapid, simple, eco-friendly, cheap spectrophotometric methods for concurrent assay of Sofosbuvir (SOF) and Simeprevir (SMV) in their pure, laboratory prepared mixture and pharmaceutical dosage form with high degree of accuracy and precision. Three methods were developed including iso-absorptive point, ratio subtraction and dual wavelength. The linear range of the proposed methods was 3.0-50.0 and 2.0-50.0 µg mL-1 for SMV and SOF, respectively. The proposed methods were validated according to ICH guidelines in terms of linearity, accuracy, precision, limit of detection and limit of quantitation. The proposed approach is highly simple and the procedure is environmentally green making it suitable for the drug analysis in routine works.

Augmentation of Brexpiprazole fluorescence through photoinduced electron transfer inhibition for the sensitive spectrofluorimetric assay of pharmaceutical dosage forms and spiked human plasma: Application to content uniformity testing.

Brexpiprazole (BRX) is a new antipsychotic drug that recently was used in the treatment of schizophrenia and other psychosis. The presence of benzothiophene ring in its chemical structure makes BRX naturally fluoresces. However, the native fluorescence of the drug was low in neutral or alkaline medium owing to the occurrence of photoinduced electron transfer (PET) from the nitrogen of the piperazine ring to the benzothiophene ring. Protonation of this nitrogen atom using sulfuric acid could efficiently block PET process and thus retaining the strong fluorescence of the compound. Accordingly, a straightforward, highly sensitive, fast and green spectrofluorimetric approach was established for BRX determination. In 1.0 M sulfuric acid solution, BRX exhibited significant native fluorescence measured at emission wavelength of 390 nm after excitation at 333 nm. ICH requirements were used to evaluate the method. The fluorescence intensity and BRX concentration were found to be correlated linearly within the range of 5-220 ng mL-1 with a coefficient of correlation 0.9999. The limit of quantitation was 2.38 ng mL-1 while limit of detection was 0.78 ng mL-1. The developed approach was successfully used to analyze BRX in biological fluids and pharmaceutical dosage form. The suggested approach worked well when applied for testing the uniformity of content.

Utilization of erythrosine B in spectrofluorimetric quenching analysis of amlodipine and perindopril in pharmaceutical and biological matrices.

A spectrofluorimetric approach that is sensitive, simple, validated, and cost-effective has been proposed for the estimation of amlodipine (AML) and perindopril (PER) in their bulk powders, pharmaceutical formulations, and spiked human plasma. The recommended approach utilized the quantitative quenching effect of the two cited drugs on the fluorescence intensity of erythrosine B, as a result of complex binary reactions among each drug with erythrosine B at pH 3.5 (Teorell and Stenhagen buffer). The quenching of erythrosine B fluorescence was recorded at 554 nm after excitation at 527 nm. The calibration curve was detected in the range 0.25-3.0 µg ml-1 , with a correlation coefficient of 0.9996 for AML, and 0.1-1.5 µg ml-1 , with a correlation coefficient of 0.9996 for PER. The established spectrofluorimetric approach was validated for the estimation of the cited drugs with high sensitivity regarding International Council on Harmonization guidelines. Therefore, the established approach could be utilized for quality control of the cited drugs in their pharmaceutical formulations.

Studying the kinetic of midodrine degradations using TLC stability approach: Application to dosage form and human plasma.

A simple, rapid and selective thin layer chromatographic method has been developed for estimation of the antihypotension drug, midodrine hydrochloride, in pure form, tablet, spiked plasma and artificially degraded samples. Separation was carried out using silica gel 60-F254 as a stationary and mobile phase consisting of methanol: methylene chloride: ammonia in ratio of 8:2:0.2. The detection was carried out at wavelength of 290 nm. The retardation factor was found to be 0.7 and 0.49 for midodrine and its main degradation product desglymidodrine. The method showed linearity for midodrine over a concentration range of 50-1500 ng/spot with good correlation and determination coefficient. The method was applied successfully for analysis of commercial tablets and oral drops with good recovery and without interference of excipients. The method also was applied for studying the stability of the cited drug under different stress conditions including acidic, alkaline, hydrolytic, oxidative and photo- degradations. Furthermore, the kinetic of acidic and alkaline degradations was investigated and the rate constants were found to be 0.620 and 0.074 K h-1 while half life time (t1/2) values were 1.12 and 9.32 h, respectively.

Feasible spectrofluorimetric approach for the ultrasensitive determination of lomefloxacin based on synergistic effects of micellization and metal complexation.

The purpose of the present work was to establish a fast and convenient strategy for lomefloxacin analysis using a fluorimetric approach. The methodology was based on the complex formation of the drug with aluminum ion to give a product having high fluorescence. Adding sodium dodecyl sulfate led to further boosting the intensity of fluorescence which was recorded at 429 nm after excitation at 332 nm. The relationship of emission intensity with lomefloxacin concentration was linear at 10-130 ng mL-1 with a correlation coefficient of 0.9996. The quantitation limit was 11.4 ng mL-1 and detection limit was 3.8 ng mL-1. The reaction conditions were carefully studied which included the pH, buffer type, its concentration, the type and concentration of surfactant and the diluting solvent. The method was utilized to quantify the aforementioned drug in tablet formulations and in real human plasma with high accuracy and reliability.