Analytical quality by design approach to RP-HPLC method development and validation for simultaneous estimation of esomeprazole and naproxen in modified-release dosage form

Background The present work describes the development and validation of a new, specific, accurate, and precise stability-indicating RP-HPLC method for the simultaneous estimation of Esomeprazole (ESP) and Naproxen (NAP) in modified-release bi-layer tablet dosage form. Analytical Quality by Design concept was implemented through the method development exercise to establish the robustness of the method. Results Method development was performed on C18, 250 × 4.6 mm ID, and 5 µm particle size column with 10 µl injection volume using a photodiode array (PDA) detector to monitor the detection at 280 nm. The mobile phase consisted of the buffer: methanol at a ratio of 50: 50 (v/v), and the flow rate was maintained at 1.5 ml/min, and the column oven temperature was maintained at 30 °C. The retention times for NAP and ESP were found 5.9 ± 0.1 and 8.9 ± 0.1 min, respectively. The method was validated in terms of system suitability, specificity, accuracy, linearity, precision, and solution stability. Linearity was observed over the range of concentration 8–12 µg/ml for ESP and 200–300 µg/ml for NAP, and the correlation coefficient (R2) was found excellent > 0.999. The method was specific to ESP and NAP, and the peak purity was found 99.97% for ESP and 100.00% for NAP. The method was precise and had %RSD less than 2. Recovery study for accuracy with placebo was found in the range of 99.63–100.36% for ESP and 99.91–100.43% for NAP. Conclusion This proposed fast, reliable, cost-effective method can be used as a quality control tool for the simultaneous determination of Esomeprazole and Naproxen in routine laboratory analysis. Graphical Abstract

Stability of Curcumin Improved in Hydrophobic Based Deep Eutectic Solvents

Turmeric is a commonly known natural spice that contains many phytoconstituents. Among which Curcumin is a polyphenol present in turmeric responsible for many pharmacological actions. Curcumin is still used as a traditional medicine in fields such as Ayurvedic, Siddha, and Unani. Though Curcumin has a large number of activities, it has disadvantages, such as small shelf life due to poor chemical stability, poor absorption results in less bioavailability, less water solubility, rapid metabolism results in quick elimination from the systemic circulation. A Deep eutectic solvent (DES) is a new class of solvents. Hydrophobic DES can be used for dissolving water-insoluble compounds. DES can be prepared when two solid components mixed in a particular proportion are converted into liquid. DES can be used as a solvent for dissolving water-insoluble compounds and to increase the stability. In this work initially, curcumin linearity studies were conducted in different buffers. A buffer showing maximum absorbance was selected from the linearity studies. Then, DES was prepared by combining Camphor:Menthol (1:1) (CM-DES), Camphor:Thymol (1:1) (CT-DES) and, Menthol:Thymol (1:1) (MT-DES). The stability of curcumin in different DES was determined from the stock and working solutions in benchtop condition (room temperature) and, refrigerator condition (5±3°C). Only working solution stability was determined in the in vitro media temperature (37±2°C). From this study, it was concluded that 50 mM Sodium dihydrogen orthophosphate with 0.5% SLS at pH 5.5 showed maximum absorbance value compared with other buffers, so it was selected for further studies. From stability studies, it was found that curcumin in CM-DES was found to be stable in both stock and working solutions compared to the other two CT-DES and MT-DES.

A Validated RP-HPLC Method for the Simultaneous Detection and Quantification of Pyridoxine and Terizidone in Pharmaceutical Formulations

Tuberculosis (TB) remains a life-threatening infection, and it is well-known that effective TB treatment is associated with multiple drugs administered to infected patients on a daily basis. Terizidone (TZD) is an anti-TB drug used in the treatment of multi-drug resistant and extensively drug-resistant TB but presents with polyneuropathic adverse effects in some patients. To counteract these adverse effects, TZD is typically prescribed with pyridoxine (PDX), well known as Vitamin B6. As part of a pre-formulation study investigating the potential to co-formulate these two compounds, it became necessary to have a simple and reliable reversed-phase high-performance liquid chromatography (RP-HPLC) method. Optimal, simultaneous separation and detection of TZD and PDX were obtained using an isocratic mobile phase setup, consisting of ultrapure water and acetonitrile (30:70% v/v), with 1 mL glacial acetic acid added to the mobile phase mixture. A Discovery® C18, 150 × 4.6 mm, 5 μm column maintained at ambient temperature was utilized, with a detection wavelength of 260 nm. The method was validated in terms of linearity, accuracy, precision, limit of detection (LOD), limit of quantification (LOQ), specificity, robustness, and solution stability. Validation proved this method to be acceptable and reliable for the simultaneous accurate detection and quantification of TZD and PDX.

Influence of a Darcy-Forchheimer porous medium on the flow of a radiative magnetized rotating hybrid nanofluid over a shrinking surface

In this paper, the heat transfer properties in the three-dimensional (3D) magnetized with the Darcy-Forchheimer flow over a shrinking surface of the $$Cu + Al_{2} O_{3} /$$ C u + A l 2 O 3 / water hybrid nanofluid with radiation effect were studied. Valid linear similarity variables convert the partial differential equations (PDEs) into the ordinary differential equations (ODEs). With the help of the shootlib function in the Maple software, the generalized model in the form of ODEs is numerically solved by the shooting method. Shooting method can produce non-unique solutions when correct initial assumptions are suggested. The findings are found to have two solutions, thereby contributing to the introduction of a stability analysis that validates the attainability of first solution. Stability analysis is performed by employing if bvp4c method in MATLAB software. The results show limitless values of dual solutions at many calculated parameters allowing the turning points and essential values to not exist. Results reveal that the presence of dual solutions relies on the values of the porosity, coefficient of inertia, magnetic, and suction parameters for the specific values of the other applied parameters. Moreover, it has been noted that dual solutions exist in the ranges of $$F_{s} \le F_{sc}$$ F s ≤ F sc , $$M \ge M_{C}$$ M ≥ M C ,$$S \ge S_{C} ,$$ S ≥ S C , and $$K_{C} \le K$$ K C ≤ K whereas no solution exists in the ranges of $$F_{s} > F_{sc}$$ F s > F sc , $$M < M_{c}$$ M < M c , $$S < S_{c}$$ S < S c , and $$K_{C} > K$$ K C > K . Further, a reduction in the rate of heat transfer is noticed with a rise in the parameter of the copper solid volume fraction.

RP-HPLC Method Development and Validation for Cleaning Residue Determination of Tofacitinib Citrate in Tofacitinib Tablets

A novel, Specific, and precise RP-HPLC method was developed to determine the residue content of Tofacitinib citrate left on the surface of equipment used in the manufacturing process. The manufacturing equipment considered in assessment of cleaning has been verified and found the tools assembled to the equipment are made up of Stainless steel, Glass, Teflon and plastic. Hence, these surfaces of manufacturing equipment that come in contact with the drug product during manufacturing are considered for evaluation of the cleaning procedure. By developing and validating an analytical method for residue estimation, the manufacturing equipment can be evaluated for efficient cleaning and to release the manufacturing equipment for further intended use by minimizing the cross contaminations. The stationary phase suited for the well separation of components is CAPCELL PAK C18 150 x 4.6 mm, 3 μm; 0.4 % perchloric acid and acetonitrile in the ratio of 85:15 % v/v is the mobile phase pumped at a flow rate of 1.2 mL/min through the column at temperature of 40 ºC. Each run extended for 10 min as the Tofacitinib peak elutes at RT of 5.2 min. The method has been validated successfully for Specificity, Precision, Linearity, Accuracy, Ruggedness and Filter validation of both rinse and swab methods. The LOD, LOQ concentrations found to be 0.006, 0.019 µg/mL for swab method and 0.03 and 0.1 µg/mL for rinse method respectively. The correlation coefficient is 0.999 and method found linear from LOQ to 500% for swab method and LOQ to 200% for rinse method. Solution stability has been established to ensure the test solution get tested within the stable time (4 Days). Based on the filter validation data, it is concluded that PVDF filter is not suitable for cleaning sample analysis and 2 mL sample should be discarded when 0.45 µm Nylon filter is used for cleaning sample analysis.

Rapid Voltammetric Screening Method for the Assessment of Bioflavonoid Content Using the Disposable Bare Pencil Graphite Electrode

Hesperidin (HESP) is a plant bioflavonoid found in various nutritional and medicinal products. Many of its multiple health benefits rely on the compound’s antioxidant ability, which is due to the presence of oxidizable hydroxyl groups in its structure. Therefore, the present study aimed to investigate the electrochemical behavior of HESP at a cheap, disposable pencil graphite electrode (PGE) in order to develop rapid and simple voltammetric methods for its quantification. Cyclic voltammetric investigations emphasized a complex electrochemical behavior of HESP. The influence of the electrode material, solution stability, supporting electrolyte pH, and nature were examined. HESP main irreversible, diffusion-controlled oxidation signal obtained at H type PGE in Britton Robinson buffer pH 1.81 was exploited for the development of a differential pulse voltammetry (DPV) quantitative analysis method. The quasi-reversible, adsorption-controlled reduction peak was used for HESP quantification by differential pulse adsorptive stripping voltammetry (DPAdSV). The linear ranges of DPV and DPAdSV were 1.00 × 10−7–1.20 × 10−5 and 5.00 × 10−8–1.00 × 10−6 mol/L with detection limits of 8.58 × 10−8 and 1.90 × 10−8 mol/L HESP, respectively. The DPV method was applied for the assessment of dietary supplements bioflavonoid content, expressed as mg HESP.

Stability-indicating RP-HPLC method development and validation for simultaneous estimation of telmisartan and rosuvastatin calcium in bulk and in tablet dosage form

Background The stability-indicating chromatographic method was developed and validated for simultaneous estimation of telmisartan and rosuvastatin calcium in bulk and in tablet dosage form. The RP-HPLC elution was carried out at 242.0 nm using column Oyster ODS3 (150 × 4.6 mm, 5 µm) isocratically, and a mobile phase containing 10 mM phosphate buffer with 1.1 g octane-1-sulfonic acid sodium salt having pH 2.5 (adjusted with 5% OPA) and acetonitrile, with a proportion of 500:500, v/v was pumped through the column maintained at ambient (about 25 °C) temperature with 1.0 mL/min flow rate. The proposed method was validated according to ICH Q2 (R1) guideline. Results Telmisartan and rosuvastatin were eluted at 2.553 min and 4.505 min, respectively. The method is linear from 99.9073 to 299.7218 µg/mL for telmisartan (R2 = 1.000) and 23.6841 – 71.0522 µg/mL for rosuvastatin (R2 = 0.999). The average recovery percentage was found 100.51, 99.76, and 99.14% for telmisartan and 99.68, 99.72, and 98.56% for rosuvastatin at three different levels. Results of method repeatability and intermediate precision were found within acceptable limits. Results of solution stability showed that mobile phase was stable for 2 days; standard and sample preparations are stable for 1 day at room temperature as well as in the refrigerator (2–8 °C). Also, forced degradation study results show that method is stability indicating as capable of distinguishing the active analytes peak from the degraded product. Conclusion The developed stability-indicating method is linear in studied concentration range as well as precise, accurate, specific, and robust. Hence, successfully this method can be used for routine analysis and stability study. Graphical abstract

Development and Validation of a Stability-Indicating UPLC Method for the Determination of Hexoprenaline in Injectable Dosage Form Using AQbD Principles

A novel and efficient stability-indicating, reverse phase ultra-performance liquid chromatographic (UPLC®) analytical method was developed and validated for the determination of hexoprenaline in an injectable dosage form. The development of the method was performed using analytical quality by design (AQbD) principles, which are aligned with the future requirements from the regulatory agencies using AQbD principles. The method was developed by assessing the impact of ion pairing, the chromatographic column, pH and gradient elution. The development was achieved with a Waters Acquity HSS T3 (50 × 2.1 mm i.d., 1.8 µm) column at ambient temperature, using sodium dihydrogen phosphate 5 mM + octane-1-sulphonic acid sodium salt 10 mM buffer pH 3.0 (Solution A) and acetonitrile (Solution B) as mobile phases in gradient elution (t = 0 min, 5% B; t = 1 min, 5% B; t = 5 min, 50% B; t = 7 min, 5% B; t = 10 min, 5% B) at a flow rate of 0.5 mL/min and UV detection of 280 nm. The linearity was proven for hexoprenaline over a concentration range of 3.50–6.50 µg/mL (R2 = 0.9998). Forced degradation studies were performed by subjecting the samples to hydrolytic (acid and base), oxidative, and thermal stress conditions. Standard solution stability was also performed. The proposed validated method was successfully used for the quantitative analysis of bulk, stability and injectable dosage form samples of the desired drug product. Using the AQbD principles, it is possible to generate methodologies with enhanced knowledge, which can eventually lead to a reduced regulatory risk, high quality data and lower operational costs.

RP-HPLC Method for Quantification of Etelcalcetide in Bulk and Parentral Dosage Form

A simple, rapid, accurate and precise RP-HPLC method was developed and validated for the determination of Etelcalcetide in bulk and parentral dosage form. Quantification of the drug was achieved on Shimadzu HPLC comprising of LC- 20 AD binary gradient pump, a variable wavelength programmable SPD-20A detector and SCL system controller. C18G column (250 mm x 4.6 mm, 5 μ) as stationary phase with mobile phase consisting of acetonitrile: methanol :water in the ratio of 25: 45 :30 v/v. The method showed a good linear response in the concentration range of 3.75-22.5 μg/ml with correlation coefficient of 0.9999. The flow rate was maintained at 1.0 ml/min and effluents were monitored at 238 nm. The retention time of etelcalcetide was 6.201 min. The method was statistically validated for accuracy, precision, linearity, ruggedness, robustness, solution stability, selectivity and sensitivity. The results obtained in the study were within the limits of ICH guidelines and hence this method can be used for the determination of etelcalcetide in bulk and parentral dosage form.

A Validated Stability Indicating RP-HPLC Method for Quantification of Cilnidipine in Bulk and in Tablet Dosage Form

A stability indicating RP-HPLC method has been developed for quantification of Cilnidipine in bulk and in tablet dosage form. The chromatographic analysis was accomplished at ambient temperature on Xttera RP18 (100 x 4.6 mm, 3.5 µm) column and 1 mL/min flow rate by using Eluent composed of 10 mM phosphate buffer pH 2.6 with Acetonitrile (300:700, v/v). The UV detection at the wavelength of 240 nm was carried out using 20 µL injection volume. The Cilnidipine retention time was found to be 3.029 min. The method in the range of 40.0573 – 120.1719 µg/mL was found to be linear (R2 = 0.999) with a detection limit and quantitation limit of 1.2038 and 3.6478 μg/mL, respectively. The mean recovery % over the three tested levels of 50, 100, and 150% were found to be 98.74, 99.60, and 98.23%, respectively. The mean % assay of 99.29 for method repeatability and 98.82 for intermediate precision were found with % RSD of 0.68 and 0.31, respectively. Cilnidipine drug substance and their product exposed to acid, alkali, oxidative, thermal, photolytic, and humidity stress conditions. The acid, alkali, and photolytic induced stress studies signifying the formation of a variety of degradants and their peaks were well resolved from that of active analyte peak. Hence, it is recommended that the Cilnidipine drug substance, as well as drug product, should be store in a tightly closed container protected from light. The method as per ICH guidelines was validated for specificity, linearity, detection limit, quantitation limit, precision, accuracy, robustness, solution stability, and can be effectively used for routine analysis.