Elution Research Articles

Development and validation of RP-HPLC method with UV-DAD detection for simultaneous determination of acesulfame K, sodium saccharin and aspartame in beverages

AbstractArtificial sweeteners are low-calorie substances used as food additives with aim to impart a sweet taste to beverages without adding significant calories. Due to the regulatory compliance regarding the type and the amount of artificial sweetener, and due to the large consumption of beverages and the effects of artificial sweeteners on human health, their identification and quantification is of a great importance. In this research simultaneous determination of acesulfame K (ACE-K), sodium saccharin (Na-SAC) and aspartame (ASP) as the most commonly used sweeteners in beverages was performed with a reversed – phase high performance liquid chromatography (RP – HPLC) with diode array detection (DAD). The best separation of the analytes was achieved on a Poroshell 120 EC-C18 (3.0 × 50 mm, 2.7 µm) column and isocratic elution with a mobile phase consisted of acetonitrile and diluted phosphoric acid (pH = 3.8) with 7/93 volume ratio (V/V), and flow rate of 1 mL min−1. The chromatographic process was followed at 195, 220 and 230 nm, under constant column temperature (25 °C). Under these chromatographic conditions, the total time of analysis was less than 5 min. The developed method was validated for linearity, precision, accuracy, limit of detection (LOD) and limit of quantification (LOQ). The LOD under established chromatographic conditions was 0.03, 0.07 and 0.17 mg L−1 for Na-SAC, ACE-K and ASP, respectively. The amount of artificial sweeteners in analyzed samples ranged from 30.32 to 148.37 mg L−1 for ACE-K, from 16.10 to 93.05 for Na-SAC, and from 6.06 to 512.72 for ASP. The validated method was successfully applied for determination of analytes in different commercially available beverages.

Выбор рационального инструментария для анализа полифенолов цветков бессмертника песчаного и листьев артишока колючего в комплексе фармакологических исследований

Background: Pathology of the hepatobiliary system includes a heterogeneous group of diseases of the liver and biliary system caused by viral, bacterial and parasitic infections, neoplasms, toxic chemicals, including alcohol, nutritional errors, metabolic disorders and heart failure. One of the basic groups for pharmacological correction of this group of diseases is the use of hepatoprotectors, drugs that have a predominantly selective effect on the liver. The active ingredient of most plant hepatoprotectors are flavonoids and hydroxycinnamic acids. The most popular plants – hepatoprotectors containing these active substances include – artichoke prickly (Cynara scolymus (L.)) and sandy everlasting (Helichrysum arenarium (L.) Moench), a plant with choleretic action, also capable of hepatoprotective activity. The aim of the study: Development and comparative characterisation of methods for the analysis of polyphenolic composition of sandy everlasting flowers and artichoke leaves in complex pharmacological studies using HPLC and capillary electrophoresis methods. Materials and methods: The sum of polyphenolic compounds was subjected to chromatographic separation in gradient elution mode. Capillary electrophoresis was carried out in a variant of micellar electrokinetic chromatography (MEKC). The buffer solution used was a mixture of: borate buffer 20 mM (pH - 9.3) – beta-cyclodextrin 20 mM – ethyl alcohol (10:10:5). Results: The electrophoregrams of the separation of artichoke leaf extract by the MECC method showed the presence of 7 components belonging to oxycinnamic acids and flavonoids. The dominant ones are chlorogenic acid and luteolin7-glucoside. Similar results were obtained by the HPLC method. The electrophoregram of immortelle flower extract shows 9 components, of which the dominant one belongs to isosalipurposide. Chromatographic analysis of sandy everlasting flower extract showed the presence of the same components. Conclusion: The results of the analysis of the polyphenolic complex of artichoke leaves and sandy everlasting flowers by capillary electrophoresis agree with the data obtained by HPLC chromatography. This allows us to conclude that the MECC method allows the identification and quantification of each component in artichoke leaves and HPLC chromatography flowers along with HPLC. Moreover, the performance of the analysis by CE is more economically feasible than HPLC, since it does not require the use of solvents for the mobile phase and the availability of a set of columns.

Simultaneous determination of acid carnosic and carnosol in rosemary-containing foods by high-performance liquid chromatography with photodiode array detection (HPLC–PDA)

The research was conducted to develop and validate a simultaneous quantification method for acid carnosic (CA) and carnosol (CAR) in rosemary-containing foods using highperformance liquid chromatography coupled with photodiode array detection (HPLC–PDA), with a simple and fast sample processing procedure. Analytical samples were extracted using a methanol–phosphoric acid mixture (99.5:0.5, v/v) at room temperature for 20 minutes. The chromatographic conditions were as follows: Sunfire C18 column (4.6 mm x 250 mm; 5 µm), mobile phase consisting of 0.1% phosphoric acid – acetonitrile (40:60, v/v), flow rate of 1 mL/min, injection volume of 10 µL, detection at 230 nm. The method was validated according to the Association of Official Analytical Chemists (AOAC) criteria. The results showed that the method had good specificity, and the standard curves of acid carnosic and carnosol were linear in the concentration range of 2.5 – 200 µg/mL. The limits of detection (LOD) for acid carnosic and carnosol were 0.3 µg/mL and 0.25 µg/mL, respectively. The limits of quantification (LOQ) for acid carnosic and carnosol were 1 µg/mL and 0.75 µg/mL, respectively. The recovery rates were in the range of 98.8 – 100.6% (acid carnosic) and 97.5 – 102.2% (carnosol). Repeatability and internal reproducibility met the requirements of AOAC. The method was applied to evaluate the acid carnosic and carnosol levels in 20 food samples collected from the market, such as rosemary leaf powder, dried rosemary leaves, rosemary herbal tea,...

An optimization through experimental design approach for simultaneous quantification of Remogliflozin and Teneligliptin by RP-UFLC

The combination of teneligliptin (TEN) with remogliflozin etabonate (REM) is the latest FDC approved for the treatment of type-2 diabetes. There is no QBD optimized UFLC method reported with short runtime for quantification of TEN and REM. Hence this research work aimed to find a new way to quantify a novel antidiabetic combination of TEN and REM using RP-UFLC technique with possible minimum run time, optimized with QBD. The method was executed using the Agilent Eclipse XDB C-18 column (150 x 4.6 mm; 5 μm), with the mobile phase comprising of buffer and acetonitrile (41:59) at a flow rate of 2.2 mL per minute and determination has been carried out at 230 nm. The retention time for TEN and REM was found at 0.770 and 1.465 minute correspondingly with runtime only 2 min. The method's effectiveness has been validated using ICH guideline for LOD, LOQ, linearity, precision, accuracy, robustness and forced degradation. In the proposed study, TEN and REM were successfully separated with very short run time of only 2 minutes. The results of validation for proposed UFLC method revealed the accuracy, specificity and forced degradation of the method. Furthermore, determination of TEN and REM from formulations showed the correctness of the method. The method is novel, easy to use, fast, precise and accurate and it can be used in QC laboratories for regular studies on API and dosages.

A sustainable RP-HPLC method for concurrent estimation of capecitabine and celecoxib in liposomal formulation: Greenness and whiteness appraisal.

Liposomes have been reported for combination therapy due to their ability to carry both hydrophilic and lipophilic drugs together. The current investigation aims to develop a novel, eco-friendly, and sustainable reverse-phase high-performance liquid chromatography (RP-HPLC) method for the simultaneous quantification of capecitabine and celecoxib co-encapsulated in liposomes. The method reported herein uses a C18 column (4.6 × 250 mm2, 5 μm) and a mobile phase consisting of water, and acetonitrile/methanol in a ratio of 60:40, containing 0.1% formic acid in both the phases. The flow rate is maintained at 1 mL/min, with an injection volume of 10 μL in the gradient mode. Detection is set at λmax = 240 nm for capecitabine and 252 nm for celecoxib. The developed liposomes are mono-disperse with a surface potential of -6.93 mV. The average size of the liposomes is 142 nm. The percentage entrapment efficiency for capecitabine is 52.39 ± 0.94%, and for celecoxib, it is 77.13 ± 0.74%. The Analytical Greenness Metric of 0.61 and Analytical Eco-Scale Score of 75 signify the greenness of the developed method. Also, the Red-Green-Blue model shows excellent whiteness, with a score of 83.2. Thus, the developed method offers a reliable, accurate, precise, buffer-free, and environment-friendly RP-HPLC approach for the simultaneous analysis of capecitabine and celecoxib co-encapsulated in liposomes.

Analytical Quality by Design (AQbD) Principles in Development and Validation of Stability‐Indicating RP‐HPLC Method for Simultaneous Estimation of Diltiazem HCl and Eugenol in Nanoethosomes

ABSTRACTThe study developed and validated a robust reverse‐phase high‐performance liquid chromatography (RP‐HPLC) method for a simultaneous estimation of Diltiazem HCl and Eugenol in nanoethosomes using analytical quality by design (AQbD) principles. The optimized method utilized a mobile phase of methanol and 0.1% Orthophosphoric acid (OPA) in a 50:50 % v/v ratio, with a flow rate of 1.0 mL/min and isocratic elution on a Phenomenex Luna C‐18 column (5 µm, 150 mm × 4.6 mm) at 30°C. This setup resulted in retention times of 6.838 min for Diltiazem HCl and 23.135 min for Eugenol. Validation followed International Council for Harmonization (ICH) Q2 (R1) guidelines, demonstrating excellent linearity with correlation coefficients of 0.9982 for Diltiazem HCl and 0.9991 for Eugenol across the 5–25 µg/mL range. The limits of detection (LOD) were 1.341 µg/mL for Diltiazem HCl and 0.960 µg/mL for Eugenol, with limits of quantification (LOQ) at 4.065 and 2.912 µg/mL, respectively. Stability testing under acidic, alkaline, oxidative, thermal, and photolytic conditions adhered to ICH Q1A (R2) and Q1B guidelines. This AQbD‐based method is effective for routine analysis of Diltiazem HCl and Eugenol in bulk and pharmaceutical dosage forms, fully complying with ICH standards.

Determination of Polyphenols in Cigar Tobacco by HPLC

A high performance liquid chromatography (HPLC) method was developed for the determination of neochlorogenic acid, cryptochlorogenic acid and caffeic acid in cigar tobacco. Firstly, the extraction method, extraction liquid concentration and dosage, column temperature and mobile phase flow rate of polyphenols in cigar tobacco were discussed. Then the detection limit, recovery rate, precision and standard curve of three polyphenols were tested. Finally, tobacco samples were tested. The results showed that the optimal extraction conditions were: ultrasonic extraction, extraction time was 30 min, methanol volume concentration was 50%, dosage was 20 mL, the optimal detection conditions were: column temperature was 30 ℃, flow rate was 1.0 mL/min, detection wavelength was 340 nm. The contents of neochlorogenic acid, cryptochlorogenic acid and caffeic acid were in the range of 0~0.202 mg/g, 0~0.331 mg/g and 0.050~0.073 mg/g, respectively, and the linear correlation coefficients of the three polyphenols were ≥0.9991, indicating that the linear correlation of the method was good, and the detection limit was ≤0.066 mg/L. The precision was ≤0.427%, and the recovery was 95.13~96.39%. The results showed that the method had good precision, high accuracy, short analysis time and high detection efficiency, and could be used as an effective method for the detection of polyphenols in cigar tobacco leaves.

Buffer-free high pH mobile phase LC-MS/MS for determination of the alcohol biomarker phosphatidylethanol 16:0/18:1 and 20 drugs and metabolites in whole blood

BackgroundAcidic mobile phases are commonly used in reversed phase liquid chromatography tandem mass spectrometry (LC-MS/MS) bioanalysis. However, increased sensitivity, improved peak symmetry, and increased retention, especially for basic hydrophilic drugs have been observed using basic mobile phases. In our previous acidic mobile phase LC-MS/MS method we needed two injections (0.4 and 2.0 μL) of each sample for this task, which is inefficient. The aim of this study was to investigate if basic mobile phase LC-MS/MS could be used to determine phosphatidylethanol 16:0/18:1 and 20 other drugs and metabolites with satisfactory sensitivity in one single run. MethodsWhole blood was prepared by 96-well supported-liquid extraction using heptane/ethyl acetate/2-propanol (16:64:20, v:v:v). Chromatographic separation was achieved on an Acquity BEH C18 column (50 × 2.1 mm I.D.), using a mobile phase with 0.025 % ammonia, pH 10.7 (Solvent A) and methanol (Solvent B). All compounds had isotope-labelled internal standards. ResultsThe method was fully validated. Recovery was between 63 and 91 % for 20 compounds and 10 % for benzoylecgonine. Matrix effects were low, except for ion enhancement of buprenorphine and ion suppression for THC. However, internal standards compensated for these effects. Inter-assay precision and accuracy were < ± 20 % for all compounds at five tested concentrations, except for methamphetamine at the highest concentration. ConclusionAn LC-MS/MS method for simultaneous determination of PEth 16:0/18:1 and 20 drugs and metabolites in whole blood were for the first time developed and validated. Retention of PEth 16:0/18:1 was, in contrast to the other 20 compounds, largely affected by mobile phase buffer concentration. The buffer free basic mobile phase ensured that phosphatidylethanol 16:0/18:1 eluted before most of the unwanted phospholipids.

Preparation of Chiral Stationary Phase Based on 1,1'-bi-2-Naphthol for Chiral Enantiomer Separation.

Two enantiomeric novel chiral stationary phases (CSPs) R-3-Amide-BINOL CSP (CSP-1) and S-3-Amide-BINOL CSP (CSP-2) were prepared using (R/S)-1,1'-bi-2-naphthol (BINOL) derivatives as chiral selectors. The structure of CSPs was characterized by nuclear magnetic resonance, scanning electron microscope and elemental analysis. Four chiral solutes were selected under normal phase HPLC conditions to evaluate the chiral separation ability of the two novel CSPs. The effects of mobile phase and acidic additives on enantiomeric separation were investigated. The combination of molecular docking simulation and experimental data has elucidated the crucial role of hydrogen bonds and π-π interactions formed between the analyte and CSP in chiral recognition, and different configurations of CSP can cause enantiomeric elution sequence reversal, indicating that the configuration of chiral selectors in CSP has a significant impact on chiral recognition ability.

Advancing Bioanalytical Method Validation: A Comprehensive ICH M10 Approach for Validating LC-MS/MS to Quantify Fluoxetine in Human Plasma and Its Application in Pharmacokinetic Studies.

A fast and sample cleanup approach for fluoxetine in human plasma was developed using protein precipitation coupled with LC-MS-MS. Samples were treated with methanol prior to LC-MS-MS analysis. Chromatographic separation was performed on a reverse phase column with an isocratic mobile phase of methanol and 10 mM ammonium formate pH acidified with formic acid (80:20, v/v) at a flow rate of 0.2 mL/min. The run time was 4 min. Mass parameters were optimized to monitor transitions at m/z [M + H]+ 310 > > 148 for fluoxetine and m/z [M + H]+ 315.1 > > 153 for fluoxetine-d5 as an internal standard. The lower limit of quantification and the dynamic range were 0.25 and 0.25-50 ng/mL, respectively. Linearity was good for intra-day and inter-day validations (R2 = 0.999). The matrix effect was acceptable with CV% < 15 and accuracy% < 15. The hemolytic effect was negligible. Fluoxetine was stable in human plasma for 48 h at room temperature (25 °C), for 12 months frozen at -25 °C, for 48 h in an auto-sampler at 6 °C, and for three freeze/thaw cycles. The validated method was applied in a pharmacokinetic study to determine the concentration of fluoxetine in plasma samples. The study provides a fast and simple bioanalytical method for routine analysis and may be particularly useful for bioequivalence studies. The method was successfully applied to a pharmacokinetic study of fixed-dose fluoxetine in nine healthy volunteers.

Rapid determination of 54 dye components in hair dyes by liquid chromatography coupled to quadrupole orbitrap high-resolution mass spectrometry.

Chemical hair dye components can have allergenic, reproductive, and carcinogenic risks. Detecting restricted and prohibited ingredients in these products is challenging due to product diversity, isomer separation, instability, and wide polarity range. A method was developed using HPLC-high-resolution mass spectrometry for the qualitative and quantitative analysis of 54 hair dye components in various products. Samples were extracted with a 70% methanol solution, ultrasonicated in an ice bath, centrifuged, filtered, diluted with 25% methanol solution and 25% methanol solution containing 0.05% D-isoascorbic acid. Separation was achieved using an ACE Excel 3 C18 column (2.1 mm × 150 mm, 3 μm) with analysis conducted via quadrupole Orbitrap mass spectrometry. It showed good linear correlations, with detection limits of 0.1-23.5 ng mL-1, and quantitation limits of 0.2-78.1 ng mL-1. Average recovery ranged from 60.0% to 118.4%, with repeatability from 4.0% to 14.9%. Stability was confirmed within 48 hours. When applied to 20 batches of commercially available hair dyes, 24 hair dye components were found within permissible levels. The method is crucial for quality control of hair dyes, covering 10 common prohibited and 44 permissible hair dye components outlined in the Safety and Technical Standards for Cosmetics (2015 Edition). Compared to the standard methods, it can separate isomers in a single mobile phase system within 15 minutes in positive ion mode while maintaining sensitivity for phenol, hydroquinone, and other components in negative ion mode. Moreover, the pre-treatment strategy significantly improved stability and accuracy, enabling precise analysis of the 54 hair dye components.

RP-HPLC-PDA-Based Simultaneous Estimation of Ramipril and Hydrochlorothiazide in Combined Dosage Forms: A Validated Approach

A rapid, highly sensitive High-Performance Liquid Chromatographic method has been developed for the simultaneous determination of Ramipril (RMP) and Hydrochlorothiazide (HCT) in bulk drug and in tablets. Ramipril (RMP) and Hydrochlorothiazide (HCT) were eluted from an Eclipse plus C18 (250 mm × 4.6 mm I.D.) with particle size 5 µm reversed phase column with a mobile phase consisting of acetonitrile and potassium dihydrogen ortho-phosphate pH 3 (40: 60 v/v) at a flow rate of 1 mL/min with UV detection at 210 nm. The retention time for RMP and HCT was found to be 3.31 ± 0.02 min and 6.64 ± 0.02 min, respectively. The linear response (r2 &lt;0.99) was observed in the range of 2 - 12 μg/mL for RMP and 4 - 24 μg/mL of HCT with low values of limits of detection (LOD) and quantification (LOQ) for both drugs. The method shows good recoveries and intra and inter-day relative standard deviations were less than 1.0%. Validation parameters as specificity, accuracy, ruggedness and robustness were also determined. The proposed method provides accurate and precise quality control tool for routine simultaneous analysis of Ramipril and Hydrochlorothiazide in bulk and in tablet dosage form.

Development and Validation of a High-Performance Thin-Layer Chromatography Method for the Qualitative Analysis and Quantification of Hispidulin in Hydroethanol Extract of S. barbata D. Don

Background: Hispidulin, a flavonoid renowned for its diverse pharmacological activities, is abundant in S. barbata D. Don. Given its prevalence, it is essential to establish a dependable analytical method for quantifying hispidulin in this plant. Methods: This study introduces a sensitive and reliable high-performance thin-layer chromatographic (HPTLC) method for both qualitative and quantitative analysis of hispidulin in S. barbata D. Don. Pre-coated TLC aluminum plates were utilized, and after testing various mobile phase combinations, the most effective separation was achieved with Toluene-ethyl acetate-formic acid (5:4:1, v/v/v). The method underwent extensive validation for linearity, specification, instrument precision, precision, limits of LOD and LOQ, accuracy, and robustness. Results: The developed method demonstrated excellent linearity over a specified concentration range, with a determination coefficient (r2) of 0.988. A well-defined spot at Rf 0.7, corresponding to hispidulin, was observed. The concentration of hispidulin in the hydroethanolic extract of S. barbata D. Don was quantified as 13.02 μg/mg of extract. Conclusion: In conclusion, the HPTLC method presented in this study offers a simple, accurate, and robust tool for quantitatively analyzing hispidulin in the hydroethanol extract of S. barbata D. Don. This method is suitable for routine quality control and standardization of herbal formulations containing S. barbata D. Don, thereby contributing to the advancement of research in natural product- based pharmaceuticals.

A Liquid Chromatography Coupled to Tandem Mass Spectrometry Method for Simultaneous Estimation of Saxagliptin and Avanafil: Application to Pharmacokinetic Drug‐Drug Interaction in Type 2 Diabetic Rat Model

ABSTRACTErectile dysfunction is a common complication of type 2 diabetes. The combination of saxagliptin and avanafil can effectively manage both conditions in individuals with type 2 diabetes. However, evaluating the potential pharmacokinetic interactions for co‐administration of saxagliptin and avanafil is crucial. Here, we developed a sensitive bioanalytical method for simultaneously quantifying saxagliptin and avanafil in rat plasma using liquid chromatography hyphenated to triple quadrupole mass spectrometry. The chromatographic separation of saxagliptin, avanafil, and irbesartan (internal standard) was achieved on an Aquity BEH C18 column (100 × 2.1 mm, 1.7 µm), using 0.1% formic acid in water and acetonitrile as mobile phase with the gradient elution at a flow rate of 0.2 mL/min. Mass detection was carried out using selective reaction monitoring mode, with the product ions for saxagliptin, avanafil, and irbesartan being 180.2, 375.1, and 207.1 m/z, respectively. The developed liquid chromatography coupled to tandem mass spectrometry method was validated as per the US Food and Drug Administration guidelines in rat plasma. The validation findings confirmed the method's robustness and suitability for accurate quantification of saxagliptin and avanafil in rat plasma with the limit of quantification of 1 ng/mL for both the drugs and were linear in the range of 1–2000 ng/mL. The study found no significant pharmacokinetic interaction between saxagliptin and avanafil, suggesting they can be safely co‐administered to patients with type 2 diabetes.

Rapid Concentration of Ga-68 and Proof-of-Concept Microscale Labeling of [68Ga]Ga-PSMA-11 in a Droplet Reactor.

The radiometal gallium-68 (Ga-68) has garnered significant interest due to its convenient production via compact and widely available generators and the high performance of 68Ga-labeled compounds for positron-emission tomography (PET) imaging for cancer diagnosis and management of patients undergoing targeted radionuclide therapy. Given the short half life of Ga-68 (68 min), microfluidic-based radiosynthesis is a promising avenue to establish very rapid, efficient, and routine radiolabeling with Ga-68; however, the typical elution volume of Ga-68 from a generator (4-10 mL) is incompatible with the microliter reaction volumes of microfluidic devices. To bridge this gap, we developed a microscale cartridge-based approach to concentrate Ga-68. By optimizing cartridge design, resin type, resin mass, and eluent composition, Ga-68 was reliably concentrated from ~6 mL to ~80 µL with high recovery efficiency (>97%, n = 14). Furthermore, this method is suitable for both single- and dual-generator setups. To demonstrate suitability of the concentrated radiometal for radiolabeling, we performed microdroplet synthesis of [68Ga]Ga-PSMA-11, achieving high radiochemical yield (83 ± 11%, n = 3), excellent radiochemical purity (>99%), and high apparent specific activity (255-320 MBq/μg). The entire process, including Ga-68 concentration, radiosynthesis, purification, and formulation, was completed in 12 min. Starting with activity of 0.81-0.84 GBq, 0.51-0.64 GBq of product was produced, sufficient for multiple patient doses. This work paves the way to clinical-scale production of other 68Ga-labeled compounds using droplet microreactor methods, or high-throughput labeling optimization or compound screening of 68Ga-labeled probes using droplet reaction arrays.

Method Development and Validation of Metformin and Gliclazide in Tablet dosage form by Micellar Liquid Chromatography

Micellar Liquid Chromatography (MLC) has emerged as a promising technique for the analysis of Pharmaceutical compounds due to its versatility, efficiency, and cost-effectiveness. In this experimental research paper, we explore the application of MLC in the simultaneous analysis of two commonly prescribed antidiabetic drugs, Metformin and gliclazide. A combination of these medicines is widely used to treat type 2 diabetes mellitus, so accurate quantification of them is essential for efficient therapeutic management. To separate the drug formulation, reversed phase liquid chromatography (RP-HPLC) was employed using surfactant solutions above Critical Miceller concentration (CMC). The mobile phase included 0.10M SDS and 10% Propanol-1, with a pH of 3.50 maintained by o-Phosphoric Acid and analysis was done using Deoxyprobe C18 column (4.6 x 150 mm, 5 µm). The separation was carried out at room temperature with a flow rate of 1.0 ml/min, and detection was performed at 228 nm. Gliclazide has a retention time of 4.46 minutes, compared to 5.57 minutes for metformin. The percentage composition of the sample under analysis ranged from 90 to 110 percent in accordance with schedule V of the Drug and Cosmetic Act. The suggested practice met ICH requirements. The method was also low-cost, easy to use, secure, and ecologically benign. It can be used to conduct standard quantitative analyses on pills that include metformin and gliclazide.

QbD-Driven Approach to Cleaning Method Development and Validation for Darunavir Analysis in Oral Films.

The current investigations involve developing a high-performance liquid chromatographic method that’s simple to operate, fast to establish, accurate, precise, and economical through design-enabled methods. A positive experimental design is offered to utilize the central composite design of pH and the mobile phase, two crucial components of the RP-HPLC technology. The chromatographic conditions were optimized with the release of Design Expert software version 13.0. Symmetry C18 column (4.6×150mm, 5µm) was used in the procedure, along with acetonitrile (20:80 v/v) and potassium dihydrogen orthophosphate buffer pH 4.0 as the mobile phase. There was a 0.70 ml/min flow rate. 263 nm is the wavelength of detection. Darunavir’s sharp, resolved peak was seen 2.3 minutes after swabbed samples from the 10*10 cm SS plate were injected. A linear calibration curve with an R2 of 0.9991 was observed in the concentration range of 0.25 to 25µg/ml. For precision %RSD is 1.03,1.48. Accuracy % concentration 50%,100%,150% mean recovery 99.43-100.53.LOD &amp; LOQ 1.12µg/ml, 3.39µg/ml. Robustness was tested with modest modifications to the wavelength and flow rate. Forced degradation studies were carried out and found to be within the limits. the degradation parameters such as Acid, Base, Oxidative, Photolytic, and thermal degradation parameters are according to the ICH guidelines. % Assay was done for oral films and it was found to be within the limits. Thus, the outcomes unequivocally demonstrated that the QbD technique could be effectively used to enhance the HPLC method for the measurement of darunavir in production settings.

(S)-2,5-dioxopyrrolidin-1-yl-1-(4,6-dimethoxy-1,3,5-triazin-2-yl)pyrrolidine-2-carboxylate derivatization combined with UPLC/ESI-MS/MS as a powerful method for dipeptide determination in foods: An application example in fermented cocoa beans

Dipeptides play a crucial role in food flavor, as well as in physiological and nutritional functions. However, as comprehensive methods for determining dipeptides are still under development, the dipeptide composition of foods remains largely unexplored. This study proposed a novel analytical method for dipeptides by applying an amino acid determination technique we previously developed: (S)-2,5-dioxopyrrolidin-1-yl-1-(4,6-dimethoxy-1,3,5-triazin-2-yl)pyrrolidine-2-carboxylate (DMT-(S)-Pro-OSu) derivatization coupled with ultra-performance liquid chromatography–electrospray ionization tandem mass spectrometry (UPLC/ESI-MS/MS). The DMT-(S)-Pro-OSu derivatization of dipeptides improved both separation in LC and detection sensitivity in MS, allowing for the optimized acquisition of m/z and elution times for 313 available dipeptides, and enabling the absolute quantification of 126 dipeptides in a simultaneous analysis. Subsequent analysis of fermented cocoa beans detected and quantified 42 dipeptides, revealing distinct dipeptide profiles depending on the origin of the beans. Additionally, by conducting in silico analysis of the elution times for 313 dipeptides, a machine learning model was constructed that accurately predicts dipeptide elution times. The DMT-(S)-Pro-OSu-UPLC/MS/MS method and the elution time prediction model developed in this study are expected to contribute to the understanding of dipeptide composition in foods.

Development and validation of High-Performance Thin Layer Chromatographic methods for simultaneous determination of antibacterial pharmaceutical formulations containing Clindamycin phosphate.

The main objective of this research is to establish and authenticate the High-Performance Thin-Layer Chromatographic techniques for the simultaneous assessment of Clindamycin phosphate in combination with Tretinoin (formulation-1) and Clindamycin phosphate with Adapalene (formulation-2), both of which are antimicrobial combinations. In the developed HPTLC methods, for combination-1, the optimized mobile phase was a mixture of n-Hexane: Ethyl acetate: ACN: Methanol (5:2:2:1 by volume) with observed Rf values of 0.413 and 0.787 for Clindamycin phosphate and Tretinoin, respectively. Similarly, for combination-2, the mobile phase comprised n-Hexane: Diethyl ether: Dichloromethane: Acetic acid (4:4:2:0.1 by volume) with recorded Rf values of 0.407 and 0.559 for Clindamycin phosphate and Adapalene, respectively. The developed methods are successfully validated as per the regulatory guidelines. This approach proves to be significantly time-saving and costeffective, rendering it suitable for routine analyses of the formulations containing selected antibacterial active pharmaceutical ingredients and commercial formulations.

Development and Validation of New Stability Indicating Analytical RPHPLC Method for Simultaneous Estimation of Metformin and Alogliptin.

The current study focuses on developing and validating a reverse phase-high performance liquid chromatography (RP-HPLC) method for quantifying metformin HCL (MET) and alogliptin (ALO) in both dosage and bulk drug forms. ALO and MET in tablet form were determined simultaneously using an RP-HPLC technique. The Reverse Phase (Waters) C18 (4.6 mm x 150 mm; 5 µ) column, a 20-injection loop are the components of the gradient system for the RP manufactured by Agilent Technologies. In the procedure, a 50:50 volumetric combination of methanol and water (0.1% acetic acid) was used as the mobile phase at pH 4.5. The developed approach yielded retention times of 3.856 minutes for MET and 6.302 minutes for ALO. The reliability of the established technique was demonstrated in compliance with the International Council of Harmonization (ICH) standards. In general, all of the metrics including linearity, accuracy, range, and robustness, were found to be within the acceptable ranges. Consequently, the methodology was assessed to be simple, precise, cost-effective, and replicable. Hence, the analysis of MET and ALO in both bulk medication and formulated states can be regularly conducted utilising the procedures specified for the purpose of quality control.