DoE-Based Analytical Quality Risk Management for Enhanced AQbD Approach to Economical and Eco-Friendly RP-HPLC Method for Synchronous Estimation of Multiple FDC Products of Antihypertensive Drugs

According to the literature review, numerous chromatographic methods have been published for estimation of fixed-dose combination products of telmisartan but no reverse-phase high-pressure liquid chromatographic (RP-HPLC) method has been published yet for synchronous estimation of fixed-dose combination (FDC) products of telmisartan to save time, cost and solvent for analysis. Hence, an economical and eco-friendly RP-HPLC method has been developed for synchronous estimation of multiple FDC products of antihypertensive drugs using the quality risk management (QRM) and DoE-based enhanced analytical quality by design approach. The analytical-QRM was started with the identification of potential method risk parameters followed by their risk assessment by risk priority number ranking and filtering. The identified critical method parameters were optimized using the DoE-based central composite design. The method operable design range was navigated and the control strategy was framed for control and mitigation of risk throughout the life-cycle of the developed method. The method was developed using Shimpack Octadecyl silane (ODS) C18 column and acetonitrile-1.0%v/v triethylamine in water (pH 6.0; 45 + 55, %v/v). The developed method was validated as per the International Council for Harmonization Q2 (R1) guideline. The developed method was applied for the analysis of seven different antihypertensive dosage forms. The developed RP-HPLC method can be used as an eco-friendly, robust and economical alternative analytical tool to several published methods for estimation of FDC products of antihypertensive drugs in the pharmaceutical industry.

Purification of Recombinant Mouse C-Reactive Protein from Pichia Pastoris GS115 by Nickel Chelating Sepharose Fast-Flow Affinity Chromatography and P-Aminophenyl Phosphoryl Choline Agarose Resin Affinity Chromatography in Tandem

C-reactive protein (CRP) is a circulating marker of inflammation yet with ill-defined biological functions. This is partly due to the uncharacterized activities of endogenous CRP in mice, the major animal model used to define protein function. The hurdles for purification and characterization of mouse CRP are its low circulating levels and the lack of specific antibodies. To clear these hurdles, here we developed an efficient expression system by constructing recombinant Pichia pastoris cells for secretion of native conformation mouse CRP. The recombinant expression of mouse CRP in Escherichia coli failed to yield sufficient amount of native protein, reflecting the importance of post-translational modification of glycosylation in aiding proper folding. By contrast, sufficient amount of native mouse CRP was successfully purified from P. pastoris. Preliminary purification was performed by Nickel Chelating Sepharose Fast-Flow affinity chromatography with 6 × His tags attached to the protein. Subsequently, p-Aminophenyl Phosphoryl Choline Agarose resin affinity chromatography was used for tandem purification. The purified mouse CRP showed native pentamer and capabilities of PC binding. Moreover, the 6 × His tag provides a convenient tool for detecting the interactions of mouse CRP with ligands.

Separation and Characterization of Novel Degradation and Process Related Impurities of Bedaquiline Bulk Drug

Bedaquiline (BDQ) is a new drug approved by United States Food and Drug Administration (USFDA) in 2012 for the treatment of drug-resistant tuberculosis, which has become a major threat globally. The manuscript presents the development of three liquid chromatography (LC) based analytical methods. The first is a stability indicating RP-HPLC (reverse phase-high performance liquid chromatography) method to analyze the BDQ in presence of its degradation products. Another UPLC/ESI–MS (ultra-performance liquid chromatography/electron spray ionization–mass spectrometry) method was developed for the identification of different degradation based and process related impurities and the third, preparative HPLC method was developed for the isolation of major degradation products. Eleven degradation products and one process related impurity were identified using UPLC/ESI–MS whereas preparative HPLC was used to isolate two degradation products and their chemical structure was elucidated using nuclear magnetic resonance, mass and infra-red spectral data.

Method Validation and Rapid Determination of Monosodium Glutamate in Various Food Products by HPLC–Fluorescence Detection and Method Optimization of HPLC–Evaporative Light Scattering Detection Approach without Derivatization

In this study, an effective, simple and rapid high-performance liquid chromatography (HPLC) using fluorescence (FLD) method was developed and validated for the determination of monosodium glutamate (MSG) in 57 various food samples. Besides, HPLC-Evaporate Light Scattering Detection (ELSD) method was carried out for determination of MSG without derivatization. MSG analysis was performed by derivatization with dansyl chloride at excitation 328, emission 530nm with fluorescence detector. HPLC-FLD method was carried out by using C18 (150 mm, 4.6 mm, 2.7 μm) column with the mobile phase consisting of (Water: Methanol:Glacial Acetic Acid)/(54:45:1,v/v/v). The column temperature was set at 25°C and the flow rate was set at 0.5 mL min−1 with an injection volume 20 μL. The results were linear (R2 = 0.9999) with very low quantification limits. The applied method was optimized and the validated parameters such as LOD, LOQ, accuracy, precision, linearity and robustness were calculated. The obtained results were statistically compared with each other. The validated HPLC-FLD method was successfully applied for the analysis of MSG in all of the food samples. Moreover, HPLC-ELSD method was optimized and successfully demonstrated for detect the MSG without derivatization.

Determination of Voriconazole in Human Plasma Using RP-HPLC/UV-VIS Detection: Method Development and Validation; Subsequently Evaluation of Voriconazole Pharmacokinetic Profile in Pakistani Healthy Male Volunteers

In this research work, an isocratic, reversed-phase high-performance liquid chromatography-ultraviolet/visible detector method was developed for analysis of voriconazole standard (stock-solution) and in plasma samples. Optimization and validation of the method was carried out as per international guidelines. The method offered a simple liquid–liquid extraction technique, which exhibited best recovery of voriconazole along with fluconazole, i.e., internal standard. Different experimental conditions were tried and ultimately, the best outcomes were accomplished utilizing C-18 Perkin-Elmer® column with particulars of 150 mm length, 4.6 mm inner diameter and 5 μm particle size, protected by an RP-18 Perkin-Elmer® Pre-column guard cartridge with specifications of 10 μm particle size, 30 mm length and 4.6 mm inner diameter, utilizing mobile-phase of acetonitrile-water (ACN: H2O) in proportion of 60: 40 v/v, having a flow rate of 1.5 mL/min, and wavelength of 254 nm. All the analytes were observed to be separated in ≤7 min. A linear calibration curve was obtained at concentration range of 01–10 μg/mL of voriconazole. The correlation coefficient of voriconazole was observed to be 0.999, and average recovery (in percent) was 97.4%, whereas the relative standard deviation value was ≤2%. The lower limit of detection was 0.01 μg/mL, whereas, lower limit of quantification was 0.03 μg/mL, respectively. This developed method provided outstanding results of all validation parameters, i.e., recovery, accuracy, selectivity, precision and reproducibility. The method proposed for voriconazole analysis was applied effectively for further research investigation of voriconazole in human-plasma samples (to assess the pharmacokinetic parameters), pharmaceutical formulations and pharmacokinetic drug–drug interaction’s.

A Novel, Simple Rapid Reverse-Phase HPLC-DAD Analysis, for the Simultaneous Determination of Phenolic Compounds and Abscisic Acid Commonly Found in Foodstuff and Beverages

A novel, simple, rapid, 7-minute HPLC-DAD method for the determination of 10 phenolic compounds and abscisic acid commonly found in teas, wines, fruit and honey was successfully developed and validated according to the International Council of Harmonization (ICH) guidelines. This reverse-phase (RP) HPLC-DAD method boasts rapid separation and excellent resolution while introducing green chemistry techniques. The Agilent 1200 series diode array detector SL coupled with a reverse-phase Advanced Materials Technology Halo C18 column (100 × 3.0 mm i.d., 2.7 μm) contributed to the rapid analyses. This, together with a 0.1% formic acid in water (v/v) and methanol mobile phase, a flow rate of 0.8 mL/min and the utilization of a meticulous gradient elution resulted in a validated method for the determination of 10 phenolic compounds and abscisic acid commonly found in various foodstuffs. The resulting method proved to be rapid, accurate, precise and linear with sensitive detection limits from 0.025 μg/mL to 0.500 μg/mL and percentage recoveries of 98.07%–101.94%. Phenolic compounds have been acknowledged throughout literature for their therapeutic properties, interalia, antioxidant, anti-inflammatory and antiaging due to free radical scavenging potentials. However, resulting analysis, can be frequently complicated and long and very often discounts green chemistry techniques. The developed and validated method successfully and rapidly analyses, gallic acid, caffeic acid, trans-p-coumaric acid, rutin, myricetin, abscisic acid, trans-cinnamic acid, quercetin, luteolin, kaempferol and chrysin with excellent resolution and precision.