Development Of High-performance Liquid Chromatography Method Research Articles

High-Performance Liquid Chromatography Method Development and Validation for Estimation of Mahanimbine in Curry Leaves

High-Performance Liquid Chromatography Method Development and Validation for Estimation of Mahanimbine in Curry Leaves

High-Performance Liquid Chromatography (HPLC) Method Validation for Identifying and Quantifying Rebamipide in Ethosomes.

Introduction The research aimed to develop a robust, high-performance liquid chromatography (HPLC) analytical method for the quantitative assessment of rebamipide encapsulated in ethosomes. Rebamipide, a quinolinone derivative, holds promise as a therapeutic agent for dry eye, but challenges such as low bioavailability and vision clouding post-installation have prompted innovative approaches. Encapsulation in ethosomes, lipid-based nanovesicles, offers a potential solution to enhance ocular bioavailability. Materials and methods The study focused on creating a specific, linear, accurate, precise, and robust HPLC method, addressing entrapment efficiency (%EE), drug content, and drug release of rebamipide in prepared ethosomes. Statistical validation followed International Conference of Harmonization (ICH) specifications. The method's parameters were evaluated within a concentration range of 4-24 µg/ml, with recovery rates indicating accuracy and low % relative standard deviation (RSD) values confirming precision. Limits of detection (LOD) and quantification (LOQ) for rebamipide were determined. Results After preparing the ethosome dosage form by film hydrating method for rebamipide, the rebamipide entrapment efficiency in ethosomes was established at 76% ± 7, while the drug content was found to be 93% ± 6. The drug release process demonstrated zero-order kineticsand five different models of kinetics were applied for a comprehensive analysis. The method exhibited excellent system suitability, specificity, and linearity. Recovery rates for rebamipide ranged from 90% to 100%, and repeatability was confirmed by low %RSD values. The LOD and LOQ for rebamipide were determined to be 1.04 μg/mL and 3.16 μg/mL, respectively. Conclusion The developed HPLC method proved suitable for the quantitative determination of rebamipide in ethosomes, offering rapid and accurate analysis. The results underscore the method's specificity, accuracy, and precision within the specified concentration range. Overall, the validated method contributes to the advancement of ocular drug delivery systems, providing a reliable analytical tool for pharmaceutical research.

Simultaneous Determination of Enantiomeric Purity and Organic Impurities of Dexketoprofen Using Reversed-Phase Liquid Chromatography-Enhancing Enantioselectivity through Hysteretic Behavior and Temperature-Dependent Enantiomer Elution Order Reversal on Polysaccharide Chiral Stationary Phases.

A reversed-phase high-performance liquid chromatographic (HPLC) method was developed for the simultaneous determination of the potential impurities of dexketoprofen, including the distomer R-ketoprofen. After screening the separation capability of four polysaccharide columns (Lux Amylose-1, Lux Amylose-2, Lux Cellulose-1 and Lux Cellulose-2) in polar organic and in reversed-phase modes, appropriate enantioseparation was observed only on the Lux Amylose-2 column in an acidified acetonitrile/water mixture. A detailed investigation of the mobile phase composition and temperature for enantio- and chemoselectivity showed many unexpected observations. It was observed that both the resolution and the enantiomer elution order can be fine-tuned by varying the temperature and mobile phase composition. Moreover, hysteresis of the retention times and enantioselectivity was also observed in reversed-phase mode using methanol/water mixtures on amylose-type columns. This could indicate that the three-dimensional structure of the amylose column can change by transitioning from a polar organic to a reversed-phase mode, which affects the enantioseparation process. Temperature-dependent enantiomer elution order and rare enthalpic/entropic controlled enantioseparation in the operative temperature range were also observed in reversed-phase mode. To find the best methodological conditions for the determination of dexketoprofen impurities, a full factorial optimization design was performed. Using the optimized parameters (Lux Amylose-2 column with water/acetonitrile/acetic acid 50/50/0.1 (v/v/v) at a 1 mL/min flow rate at 20 °C), baseline separations were achieved between all compounds within 15 min. Our newly developed HPLC method was validated according to the current guidelines, and its application was tested on commercially available pharmaceutical formulations. According to the authors' knowledge, this is the first study to report hysteretic behavior on polysaccharide columns in reversed-phase mode.

Reverse‐phase high‐performance liquid chromatography methodology for film‐forming mafenide spray: Compatibility, assay, and in‐vitro release evaluation using Franz vertical diffusion cell apparatus

AbstractThis paper described a short and precise reverse‐phase high‐performance liquid chromatography (HPLC) method for quantifying mafenide in a film‐forming spray and preliminary in‐vitro release study. Following the International Council for Harmonization guidelines Q2 (R1), the method was validated. The chromatographic separation was achieved using a 10 mM potassium dihydrogen phosphate solution (mobile phase A) mixed with HPLC‐grade methanol (mobile phase B) in an 85:15 v/v ratio. Inert Sustain C8 (4.6 × 250 mm), 5 μm column was selected as the stationary phase. The flow rate was set as 0.8 mL/min, and detection was carried out at a wavelength of 222 nm. The developed HPLC method showed an accuracy between 98% and 102%. The primary diffusion study of film‐forming spray was performed using the Franz vertical diffusion cell apparatus. It was observed that an average of 26.94% of drug releases at 24 h. This indicates the drug has a slower release rate and shows local pharmacological action. The Weibull dissolution model was more fitting with regression square 0.9953. Furthermore, the drug excipient compatibility study revealed no interactions as the only drug peak was found in the chromatographic method, indicating that the chosen excipients were appropriate for a stable formulation.

HPLC Method Development and Validation for the Determination of Apixaban and Clopidogrel in Novel Fixed-Dose Combination Tablets

A simple, fast, and accurate high-performance liquid chromatographic (HPLC) method is developed, optimized, and validated for a fixed-dose combination of apixaban (APX) and clopidogrel (CLOP) tablets according to ICH guidelines. Chromatographic separation of the drugs was performed on a BDS Hypersil C18 (4.6 ∗ 150 mm, 5 μm), with acetonitrile (ACN) and trifluoroacetic acid (TFA) in the ratio 48 : 52 (v/v) as a mobile phase, at a flow rate of 0.9 ml/min., injection volume of 5 μL, and column temperature 45°C. The proposed method was linear over the level 25–200% for a concentration of APX 5 μg/ml and CLOP 75 μg/ml (R2 > 0.999). The detection limit for APX and CLOP was found to be 0.3465 and 3.8496 μg/ml, whereas the quantification limit was 1.0499 and 11.6656 μg/ml, respectively. The recovery was more than 99% using the standard addition method. The developed method was found to be specific, accurate, precise, and robust against changes in column temperature (±5°C) and mobile phase composition (±5% ACN); hence, it can be used for the determination of APX and CLOP in the fixed-dose combination tablets.

Advances in High-Performance Liquid Chromatography (HPLC) Method Development and Validation: A Comprehensive Review

High-Performance Liquid Chromatography (HPLC) stands as the cornerstone technique for the detection, separation, and quantification of drugs in various matrices. Method optimization necessitates a thorough investigation of multiple chromatographic parameters, encompassing sample pretreatment, mobile phase composition, column selection, and detector configuration. This article aims to comprehensively address the processes of method development, optimization, and validation within the realm of HPLC. The inherent advantages of HPLC, including its rapidity, specificity, accuracy, precision, and automation feasibility, render it an indispensable tool for analyzing a wide spectrum of drugs in complex multi-component dosage forms. Furthermore, HPLC method development and validation hold paramount importance across the spectrum of drug discovery, development, and manufacturing, as well as in diverse human and animal studies. The validation of analytical methods during drug development and manufacturing is imperative to ensure their fitness for the intended purpose. Adhering to Good Manufacturing Practice (GMP) requirements, pharmaceutical industries must establish comprehensive validation policies outlining the validation procedures. This article primarily delves into the optimization of HPLC conditions, emphasizing the critical role of method refinement in ensuring robust and reliable analytical methods.

Eco-Friendly Stability Indicating HPLC Method for Estimation of Elbasvir and Grazoprevir by Quality by Design Approach

Introduction: The pharmaceutical industry faces a significant problem as a result of the worldwide requirement to modify processes in order to comply with the green analytical chemistry (GAC) requirements. An enormous amount of organic hazardous waste is produced by high-performance liquid chromatography (HPLC), one of the methods employed the most frequently at different stages in the pharmaceutical sector. Aim: To develop analytical quality by design-aided stability indicating green high-performance liquid chromatography (HPLC) method for estimation of Elbasvir and Grazoprevir in a dosage form. Material and Methods: The critical chromatographic factors were the % of ethanol in the mobile phase, flow rate, and their overall effect on the responses like asymmetry, theoretical plates, and resolution were studied to optimize the method. Green analytical chemistry (GAC) has mainly focused on developing analytical methods that are safe for the environment. Therefore, it is imperative that the GAC principles be applied in pharmacological analysis. A rotatable central composite design was employed, and the optimized conditions for chromatographic separation were made with a run time of 5 minutes using Zorbax C18 column (4.6× 150 mm, 5 µm) with 0.1% Trifluoroacetic acid and ethanol (40:60 v/v) as components of a mobile phase, flowing at a rate of 1.0 ml/minute. Photodiode array detection was carried out at 253 nm. Results: The retention time was 1.8 min for EBS and 2.84 min for GZP. According to the ICH guidelines, the proposed method was validated and stress studies revealed that Elbasvir and Grazoprevir are prone to acidic, basic, and oxidation stress conditions. An analytical eco-scale score evaluated the greenness profile and a software-based evaluation. Conclusion: The developed HPLC method is eco-friendly and shall be adopted   in the routine quality control of Elbasvir and Grazoprevir in a tablet dosage form.

Quality-by-Design-based development of an eco-friendly HPLC method for the estimation of nisoldipine in nanoformulations: Forced degradation studies and in-vitro release studies

The current study focuses on optimizing, developing, and validating a sensitive and specific high-performance liquid chromatography (HPLC) method for the quantification of nisoldipine (NLD) in bulk and nanoformulations. Design of Experiments (DoE) was utilized to optimize the HPLC method. The critical method parameters (CMPs) were screened using the Taguchi OA design. The selected variables were further optimized using the Box-Behnken design with the retention time (Rt), peak area, and the number of theoretical plates (NTP) as the dependent variables. The optimal chromatographic parameters were: flow rate: 0.8 mL/min, injection volume: 20 μL, and concentration of acetonitrile: 70% v/v. The Rt, peak area, and NTP were 8.546, 656065, and 4234.4, respectively. The optimized method demonstrated excellent linearity (R2 = 0.9994), having a range of 100–4000 ng/mL, and LOD and LOQ were 25.42 and 77.06 ng/mL, respectively. The sensitivity, accuracy, precision, specificity, and robustness of the developed HPLC technique were in accordance with the regulatory guidelines. It also exhibited specificity for NLD in the presence of degradants. The HPLC technique was also employed to estimate the drug content of NLD nanosuspension and for in-vitro dissolution study. The eco-friendliness of the developed method was compared with reported methods by employing tools such as analytical eco-scale, GAPI, and AGREE. The developed method was found to be greener than the reported methods.

Preformulation-Assisted Design of Ketorolac Tromethamine for Effective Ophthalmic Delivery.

Background: The eye is a highly protected organ from ocularly administered drugs; drug- and formulation-related factors contribute significantly to ocular bioavailability. There has been a growing interest in using nonsteroidal anti-inflammatory drugs in ophthalmology for treating postoperative pain, inflammation, and seasonal allergic conjunctivitis. A preformulation-assisted design boosts efficacy and reduces dose requirements. Methods: This work aims to study the preformulation characteristics of ketorolac tromethamine to improve ocular performance and future formulation development through developing an high-performance liquid chromatography (HPLC) stability-indicating assay, forced degradation under stress conditions, solubility, as well as partition and distribution coefficient measurements. An isocratic HPLC with diode array detector method was developed and validated. Accelerated degradation under different stressors (acid, alkali, heat, and oxidative) was studied. In addition, solubility, partition, and distribution were investigated at different pHs of 3.5-7.4. Results: The results indicated that the developed HPLC method was simple, rapid (retention time ≃3 min), sensitive, selective, robust, and stability indicating. The drug seems more chemically sensitive to acid degradation (∼30% and 40% of the drug was degraded under 0.1 M and 1 M HCl at 60°C for 24 h, respectively). Another significant degradation was recorded in the following order: Oxidative > alkali > heat (phosphate-buffered saline) > heat (distilled water). Being a weak ionizable drug, both water and lipid solubility, as measured through partition coefficients, it demonstrated pH-dependency. Conclusion: For the optimum balance of water and lipid solubility required for penetration through the lipophilic corneal epithelial barrier, ketorolac eye drops would be better formulated between pH 5.5 and 6.6 than being formulated at the physiological fluid pH 7.4, where the drug is extremely hydrophilic and less permeable.

Advancing posaconazole quantification analysis with a new reverse-phase HPLC method in its bulk and marketed dosage form.

Introduction: Posaconazole is a widely used antifungal drug, and its accurate quantification is essential for quality control and assessment of its pharmaceutical products. This study aimed to develop and validate a reverse-phase high-performance liquid chromatography (HPLC) analytical method for quantifying Posaconazole in bulk and dosage form. Methods: The HPLC method was developed and validated based on International Conference on Harmonisation (ICH) guidelines. The developed method was then applied to quantify Posaconazole in a marketed tablet formulation. The method's specificity, linearity, precision, accuracy, robustness, and stability were evaluated. Results: The developed HPLC method showed good linearity over a 2-20 μg/mL concentration range. The percentage recovery of Posaconazole from the bulk and marketed formulations was found to be 99.01% and 99.05%, respectively. The intra-day and inter-day precisions were less than 1%, and the method was stable under different conditions. The HPLC method was successfully applied to quantify Posaconazole in the marketed formulation. Conclusion: The developed and validated HPLC method is reliable and efficient for analyzing Posaconazole in bulk and dosage forms. The method's accuracy, precision, specificity, linearity, robustness, and stability demonstrate its effectiveness. The method can be used for the quality control and assessment of Posaconazole-containing pharmaceutical products.

Advancing posaconazole quantification analysis with a new reverse-phase HPLC method in its bulk and marketed dosage form

Introduction: Posaconazole is a widely used antifungal drug, and its accurate quantification is essential for quality control and assessment of its pharmaceutical products. This study aimed to develop and validate a reverse-phase high-performance liquid chromatography (HPLC) analytical method for quantifying Posaconazole in bulk and dosage form. Methods: The HPLC method was developed and validated based on International Conference on Harmonisation (ICH) guidelines. The developed method was then applied to quantify Posaconazole in a marketed tablet formulation. The method's specificity, linearity, precision, accuracy, robustness, and stability were evaluated. Results: The developed HPLC method showed good linearity over a 2-20 μg/mL concentration range. The percentage recovery of Posaconazole from the bulk and marketed formulations was found to be 99.01% and 99.05%, respectively. The intra-day and inter-day precisions were less than 1%, and the method was stable under different conditions. The HPLC method was successfully applied to quantify Posaconazole in the marketed formulation. Conclusion: The developed and validated HPLC method is reliable and efficient for analyzing Posaconazole in bulk and dosage forms. The method's accuracy, precision, specificity, linearity, robustness, and stability demonstrate its effectiveness. The method can be used for the quality control and assessment of Posaconazole-containing pharmaceutical products.

Stability indicating HPLC method development and validation of Fostemsavir in bulk and marketed formulations by implementing QbD approach

Background: Achieving a predictable degree of quality with intended and planned specifications is known as "quality by design." QbD (Quality-by-Design) is an alternative to conventional method development that places more attention on identifying and mitigating potential risks. Component of the Quality-by-Design methodology involves conducting a series of experiments to learn how various factors, including the dependant variables, affect the answers of interest. Here, we use a QbD (Quality-by-Design) loom to detail the creation and verification of a stability-indicating high-performance liquid chromatography (HPLC) method for Fostemsavir in both bulk and finished-goods forms.
 Results:
 In this work, we present a workable experimental design for optimising the RP-HPLC separation technique by identifying the optimum mobile phase concentration and flow rate. Below are the ideal chromatographic conditions as calculated by Design Expert version 13.0: Mobile phase: 80 parts acetonitrile to 20 parts formic acid (v/v), flow rate: 0.8 millilitres per minute, retention time: 3.24 minutes, column dimensions: GIST C18 (250 mm × 4.6 mm × 5.0 μm).
 Here we propose a practical experimental layout for determining the optimal mobile phase concentration and flow rate for the RP-HPLC separation technique. Using Design Expert version 13.0, the optimum chromatographic conditions were determined to be as follows: Shim-pack GIST C18 (250 mm 4.6 mm, 5.0 μ), mobile phase acetonitrile to 1% formic acid (80:20, v/v), flow rate 0.8 ml/min, and retention period 3.24 min.
 At a detection wavelength of 266 nm, it was discovered that the devised technique was linear over a concentration range of 50-90 μg/ml (r2 = 0.997). Test parameters for the system's appropriateness were determined to be 1.124 for the tailing factor and 9480 for the theoretical plates. Intraday RSD was found to range from 0.70 to 0.94, whereas interday RSD was found to range from 0.55 to 0.95 percent. Values for robustness were under 2%. The solution stability % RSD was calculated to be 0.83. The result of the assay was 100.05 percent. The created methodologies were used to studies of forced degradation, and the stressed materials were analysed. The parameters used to validate the procedure fell within the acceptable range recommended by ICH.
 Conclusion: Using Design Expert 13.0, we created a central composite design experiment that illustrates the relationships between mobile phase and flow rate across three levels, with retention duration, tailing factor, as well as theoretical plates as the responses of interest.  By this work, we gain insight into the variables that affect chromatographic separation and strengthen our conviction that the HPLC method we've devised will serve our needs. Quantitative method development was applied to improve comprehension of multi-tiered method variables.

Advances, Applications, and Challenges in RP HPLC Method Development

High-performance liquid chromatography (HPLC) has become an indispensable tool for modern analytical chemistry, and reversed-phase (RP) HPLC is one of the most widely used techniques for the separation and analysis of complex mixtures. In recent years, there have been numerous advances in RP HPLC method development, including the development of new stationary phases, improved column technology, and novel optimization strategies. These advances have led to increased speed, resolution, and sensitivity, as well as improved selectivity and reduced non-specific adsorption. Moreover, RP HPLC has found applications in a wide range of industries, including pharmaceuticals, food and beverage, environmental analysis, forensic science, and biotechnology. Despite its many benefits, RP HPLC method development is not without its challenges, including issues with column stability, sample preparation, and optimization. In this review article, we provide a comprehensive overview of the principles, optimization strategies, and recent advances in RP HPLC method development. We discuss the applications of RP HPLC in various industries and identify the common challenges and emerging trends in the field. Additionally, we evaluate the impact of RP HPLC on the accuracy, sensitivity, and selectivity of analysis and its potential to improve the quality and safety of products and the environment. Overall, this review highlights the importance of RP HPLC in modern analytical chemistry and provides insights and recommendations for researchers and practitioners who are interested in this technique. By exploring the latest advances, applications, and challenges in RP HPLC method development, we hope to inspire continued innovation and progress in this important field.

Development and validation of HPLC method for ximenynic acid in semisolid dosage formulation

A novel analytical technique and validation study were developed to determine the concentration of ximenynic acid (XMA) in semisolid dosage formulations (SDF) such as cream, gel, lotion, etc. The procedure makes use of reverse-phase high-performance liquid chromatography (HPLC). A Phenomenex Luna Column 5 (4.6 x 250 mm) was used for the analysis, using acetonitrile as the mobile phase, sodium dihydrogen phosphate monohydrate as the stationary phase, and 229 nm detection at 30 degrees Celsius. In spite of the presence of additional compounds, their presence had no effect on the detection of XMA in SDF. As part of validating this HPLC technique, a number of tests were performed to evaluate its specificity, linearity, accuracy, precision, and durability. International Conference on Harmonization standards were used to determine whether the method was adequate (ICH). Because it is simple to implement and produces reproducible results, the presented HPLC approach has the potential to be utilized in industry to standardize herbs and Phytomedicines. Because XMA has the potential to be a game-changing method of treating ageing, its advancement may benefit the pharmaceutical and cosmetics sectors.

High-performance liquid chromatography method development and validation for the quantification of mangiferin in Coffea arabica leaves

Introduction and Aim: Mangiferin is accompanied by the therapeutic potential for various human ailments. The present study is aimed to develop a validated HPLC method for the quantification of mangiferin in coffee (Coffea arabica) leaves.
  
 Materials and Methods: The ­­high-performance liquid chromatography (HPLC) was carried out on Agilent Technologies 1260 LC Infinity Series liquid chromatography system (Agilent, USA) using an isocratic mobile phase of a mixture of methanol and 1% orthophosphoric acid v/v (70:30) at a flow rate 1mL min-1 for 14 min with the controlled temperature at 25°C. The mangiferin content was detected by a UV diode array detector at 258 nm.
  
 Results: The linearity of the HPLC system was established in the range of 10-100 ppm mL-1 with a regression coefficient (R2) of 0.99670. The accuracy of the method was assessed by a study performed using 3 different levels, with a 99% average recovery. The limit of detection(LOD) and limit of quantification (LOQ) were 1.3 and 3.9 ppm mL-1. Intraday and interday precision analysis showed the relative standard deviation 0.012342 separately. The content of mangiferin in the coffee leaves was 94 mg/gram (w/w).
  
 Conclusion: All necessary factors, such as linearity, accuracy, LOD, LOQ, precision, and % relative standard deviation(RSD), were inside the appropriate limits. The HPLC was validated using all necessary variables with a successful estimation of mangiferin.

[Analysis and evaluation on Paeoniae Radix Alba from different cultivars by UPLC-Q-TOF-MS and HPLC].

In this study, an established ultra-high performance liquid chromatography coupled with quadrupole-time-of-flight mass spectrometry(UPLC-Q-TOF-MS) method was combined with multivariate statistical analysis to investigate the commonality and difference of main chemical components in the medicinal parts of Paeonia lactiflora from different cultivars; in addition, a high performance liquid chromatography(HPLC) method was established to simultaneously determine the content of eight active components in Paeoniae Radix Alba. Non-targeted analysis was carried out by UPLC-Q-TOF-MS on a Waters ACQUITY UPLC BEH C_(18)(2.1 mm×100 mm, 1.7 μm) column with a gradient elution of 0.1% aqueous formic acid(A)-acetonitrile(B) as the mobile phase at a flow rate of 0.2 mL·min~(-1). The column temperature was 30 ℃, and an electrospray ionization source was used to acquire mass spectrometry data in positive and negative ion modes. According to the accurate molecular weight and fragment ion information provided by multi-stage mass spectrometry and by comparison with reference substances and literature reports, thirty-six identical components were identified in Paeoniae Radix Alba from different cultivars with positive and negative ion modes. In the negative ion mode, two groups of samples were well separated; specifically, seventeen components with significant differences in content were screened and identified, and one component unique in "Bobaishao" was obtained. Quantitative analysis was conducted by high-performance liquid chromatography(HPLC) on an Agilent HC-C_(18)(4.6 mm×250 mm, 5 μm) column with a gradient elution of 0.1% aqueous phosphoric acid(A)-acetonitrile(B) as the mobile phase at a flow rate of 1.0 mL·min~(-1). The column temperature was 30 ℃ and the detection wavelength was at 230 nm. An HPLC method was developed for the simultaneous determination of eight active components(gallic acid, oxypaeoniflorin, catechin, albiflorin, paeoniflorin, galloylpaeoniflorin, 1,2,3,4,6-O-pentagalloylglucose, benzoyl-paeoniflorin) in Paeoniae Radix Albaa from different cultivars. Satisfactory linearity was achieved within the investigated linear ranges and with fine coefficients(r>0.999 0), and the methodological investigation showed that the method had good precision, repeatability and stability. The mean recoveries were 90.61% to 101.7% with RSD of 0.12% to 3.6%(n=6). UPLC-Q-OF-MS provided a rapid and efficient qualitative analytical method for the identification of the chemical components in Paeoniae Radix Alba, and the developed HPLC method was simple, rapid and accurate, which could provide a scientific basis for the evaluation of the germplasm resources and herbal quality of Paeoniae Radix Alba from different cultivars.

Comparative Investigation Between Raw and Stir-Frying Processed Cuscutae Semen Based on HPLC Fingerprints Coupled With Chemometric Methods.

The curative effect of Cuscutae Semen (CS) could be adjusted after stir-frying, and it is difficult to distinguish between the raw CS and stir-fried processed Cuscutae Semen (SFCS) in clinical practice. The paper aims to establish the fingerprints of raw and fried Cuscutae Semen products by high-performance liquid chromatography (HPLC) so that the compounds in raw and stir-fried products could be analyzed qualitatively and quantitatively. At the same time, the chemometrics method was used to evaluate the difference between CS and SFCS to provide reference for the research of traditional Chinese medicine (TCM) CS. The raw and SFCS products' related substances were separated on a C18 column (250 mm × 4.6 mm, 5 µm) maintained at 30 °C (column temperature). The mobile phase comprised 0.1% formic acid aqueous solution (A) and acetonitrile (B), and a detection wavelength of 328 nm. The data were imported into statistical software for chemometric analysis. The developed HPLC method exhibits good linearity and has good systematic applicability. The content of these 12 compounds in the samples was further determined and the data analyzed by chemometrics. The results showed that the composition of CS changed on heating, and HCA showed that CS and SFCS could be clearly distinguished. PCA showed that six components caused differences, namely neochlorogenic acid, cryptophyllogenic acid, caffeic acid, quercetin, isorhamnetin, and kaempferol. This study unequivocally establishes a chromatographic fingerprint method intended for the extensive analysis of raw and stir-fried processed CS, which could substantially enhance the quality control of CS and the rational development and utilization of TCM resources. This method for the simultaneous quantification of multiple compounds in CS and SFCS revealed the components responsible for the differences between raw and processed products. This will provide support for quality control of this herbal medicine.

Development of HPLC Fingerprinting Method via Estimation of Piperine for Unani Formulation Hab-e-Azarakhi

Hab-e-Azarakhi is an important Unani formulation, is official in Unani Pharmacopoeia. The formulation is dispensed for the tone up the nervous system and liver. It is also useful for increase the appetite. Fingerprinting of active principles through modern analytical tools is essential for establishing the authenticity, creditability, prescription and usage of Traditional medicines/herbal formulations. Selective and efficient analytical methods are required not only for quality assurance but also for authentication of herbal formulations. The present study is an attempt to develop Fingerprint method for Hab-e-Azarakhi with High Performance Liquid chromatography (HPLC) using piperine as a standard was developed. The estimation was carried out with three laboratory batches and one marketed formulation of Hab-e-Azarakhi. The concentration of piperine content of Hab-e-Azarakhi (three laboratory batches) and powdered Piper nigrum and Piper longum was carried out separately. The concentration of piperine present in raw material was found to be 2.9876±0.837%w/w in Piper nigrum and 0.9363±0.167% w/w in Piper longum and in three identical laboratory batches of Hab-e- Azarakhi HA-I, HA-II and HA-III 1.8121±0.739%, 1.8806±0.439%, 1.8901±0.779% w/w respectively, while in M-I it was 1.2108 ± 0.182%. The developed HPLC method is simple, rapid, precise and accurate for routine estimation piperine in Hab-e- Azarakhi.

Quantitation of Venetoclax in Human Plasma by High-Performance Liquid Chromatography with Ultraviolet Detection.

A simple, highly sensitive and specific method based on high-performance liquid chromatography (HPLC) with ultraviolet detection was developed for the measurement of venetoclax concentrations in plasma samples. The chromatographic method employed a mobile phase of acetonitrile: 0.5% KH2PO4 (pH3.5) (80/20, v/v) on a CAPCELL PAK C18 UG120 column at a flow rate of 0.5mL/min. The quantitative method was validated based on standards described in "Bioanalytical Method Validation: Guidance for Industry" published by the US Food and Drug Administration. The separation of venetoclax and the internal standard R051012 was satisfactory, and the chromatograms were free of interfering peaks from the biological matrix. The intra- and inter-day coefficients of variation for venetoclax assays were <12.9%, whereas intra- and inter-day accuracies were within 13.6%. Only 100μL of human plasma was required to detect a lower limit of quantification of 10ng/mL for venetoclax. The recoveries of venetoclax extracted with an Oasis HLB cartridge were between 81 and 85%. The developed HPLC method was successfully applied to the determination of venetoclax concentrations in plasma of acute myeloid leukemia patients taking venetoclax. The degree of drug interactions between venetoclax and CYP3A4 inhibitors can be determined by this HPLC assay.

Normal-Phase TLC and Gradient Reversed-Phase HPLC for the Simultaneous Determination of Enrofloxacin and Bromhexine HCl in Presence of Two of Their Official Impurities.

In this work, two chromatographic methods are developed and validated for the determination of enrofloxacin and bromhexine (BRM) HCl in the presence of two of their specified impurities, ciprofloxacin and BRM impurity C. The suggested chromatographic methods included the use of thin layer chromatography (TLC-densitometry) and high-performance liquid chromatography (HPLC). In case of TLC-densitometry, good separation was achieved by using mobile phase of n.butanol:acetone:water:glacial acetic acid:triethylamine (10:3:1:0.5:0.5, by volume) on silica gel stationary phase at 254-nm detection. The developed HPLC method used BDS HYPERSIL C18 column with a mobile phase of water:acetonitrile:methanol:triflouroacetic acid. A linear gradient elution of 75-10%, 20-50% and 5-40% for water, acetonitrile and methanol, respectively, was applied in 13min at a flow rate of 1.5mLmin-1. These methods were sufficient to separate the four substances simultaneously, and they are validated as per International Conference on Harmonization guidelines.