PDA Detector Research Articles

POLYPHENOLS CONTENT OF MEDICAL PLANTS AND FOOD SUPPLEMENTS IN BULGARIA

Objective: Flavonoids have proven beneficial effects on cardiovascular system.Medicinal plants are a rich source of antioxidant polyphenols and in particular flavonoids. Recently many food supplements has gained popularity, despite of lack of evidence based data and strict regulatory control. Design and method: In the present study 5 Bulgarian medical plants and 5 food supplements, present at the Bulgarian market, were analyzed for their Total phenolic, Total flavonoids and selected individual flavonoids content. A HPLC method was developed and validated for simultaneous determination of (+)-catechin, (-)-epicatechin and rutin in plant and supplements, using PDA detection. Results: The results show that polyphenols in the selected food supplements are lower than those of the medical plants analyzed. Mentha piperita and Melissa officinalis have the highest polyphenols content (67.38 and 65.17 mg GAE/g; 54.59 and 57.76 mg RE/g respectively). Rutin was detected in all samples analyzed, reaching highest levels in Mentha piperita (7332.5 g/g), followed by fruits of Sambucus nigra (2818.7 g/g). Conclusions: The results of the study are a practical contribution to a more complete characterization of the polyphenolic composition in Bulgarian medicinal plants.They also showed that medical plants, used in traditional folk medicine may be a more effective and cheaper alternative to food supplements.

New stability indicating RP-UFLC method for the quantification of Efavirenz in pharmaceutical dosage forms

Efavirenz is an active non-nucleoside reverse transcriptase inhibitor used for the treatment of human immunodeficiency virus (HIV) type 1. A simple and validated new stability indicating RP-UFLC method has been developed for the estimation of Efavirenz in pharmaceutical dosage forms i. e. tablets. Shimadzu UFLC system (PDA detector) with Zorbox C18 column was chosen for the chromatographic study with flow rate 1.2 mL/min (UV detection at 252 nm). Beer-Lambert’s law was obeyed over a concentration range 0.05-160 µg/mL. The linear regression equation was found to be y = 44317x + 8491.1 (R2 = 0.9993). The LOD and LOQ was found to be 0.0142 and 0.0429 µg/mL respectively. Stress degradation studies were performed and the method was validated as per ICH guidelines. The proposed method is simple, precise, accurate and robust and can be applied for the quantification of Efavirenz formulations.

Development and validation of a new stability indicating RP-HPLC method for the quantification of Budesonide in pharmaceutical dosage forms in presence of an internal standard

Budesonide is a glucocortico steroid used for the treatment of nasal polyposis, asthma and Crohn’s disease. A stability indicating RP-HPLC method has been developed and validated for the quantification of Budesonide in pharmaceutical dosage forms in presence of an internal standard, Etoricoxib. Mobile phase including a mixture of formic acid: acetonitrile: methanol (25: 10: 65) was chosen for the chromatographic study with flow rate 1.0 ml/min. The PDA detection was carried at 240 nm and the elution was achieved on isocratic mode using Zorbox C18 column. Beer-Lambert’s law was obeyed over a concentration range 0.05-120 µg/ml and the linear regression equation was y = 0.0489x + 0.003 with correlation coefficient 0.9997). The LOQ and LOD was found to be and 0.0393 and 0.1192 µg/ml. Stress degradation studies such as acidic hydrolysis, alkaline hydrolysis, oxidation and thermal degradation were performed. The method was validated for the parameters linearity, precision, accuracy, robustness as per ICH guidelines and the proposed stability indicating liquid chromatographic method was found to be simple, accurate, precise and robust and can be applied for the assay Budesonide formulations.

RP-HPLC method for swift analysis of Lamivudine and Dolutegravir in formulation, stability studies

New RP-HPLC method have been developed for simultaneous analysis of lamivudine and dolutegravir in pharmaceutical dosage forms and applied to stability studies of drugs. The title analytes were eluted rapidly with phosphate buffer (pH 5.0) and acetonitrile (60:40 v/v) on Std discovery C18 (150 x 4.6 mm, 5 µ) column. The detection was carried out using PDA detector at 260 nm. The solutions were chromatographed at a constant flow rate of 1 mL/min. Lamivudine and Dolutegravir were eluted at 2.37 min and 2.97 min respectively with good resolution. Method was validated as ICH guidelines. The linearity range of lamivudine and dolutegravir were found to be of 18.75 - 112.5 µg/mL and 3.125 - 18.75 µg/mL, respectively. The % RSD values (< 2) in precision studies indicates the reproducibility of method. The percentage recoveries were 100.17 % and 100.36 % respectively for lamivudine and dolutegravir, found to be within the limits. The proposed validated method was fruitfully applied for assay of formulation and stability studies of drugs under various stress conditions.

The validated method for the analysis of a mixture of psychotropic medicines olanzapine, clorazepate and escitalopram using a high-performance liquid chromatography method

It was established that self-poisoning with antipsychotics, anti-anxiety drugs and antidepressants is caused by consumption of the drug in higher doses than prescribed. So it is very important to determine fast the materials causing poisoning and use the method which would allow one to identify several substances during only one analysis. Reference and test solutions were prepared in ethanol. A qualitative and quantitative analysis was carried out on a Waters Alliance 2695 liquid chromatograph equipped with a Waters 996 PDA detector and an ACE C18 (250 mm × 4.6 mm × 5 μm) column. The mobile phase consisted of solvent trifluoroacetic acid (0.1 %) and acetonitrile. The linear gradient elution profile was used. For the validation process the following parameters were chosen: specificity, repeatability, precision and limits (LOD and LOQ). According to the study results, it can be concluded that the validated method for the qualitative and quantitative evaluation analysis of olanzapine, clorazepate and escitalopram was developed.

RP-HPLC Method development and validation for simultaneous estimation of montelukast and ebastine in pharmaceutical dosage form

Combination therapy of Montelukast (MNK) and Ebastine (EBA) provide anti-asthmatic effector the maintain treatment of asthma and relieve symptoms of allergies. The objective of this study is development of a new simple, accurate, sensitive, and reproducible RP-HPLC method for simultaneous estimation of MNK and EBA in pharmaceutical formulation (tablet) using Ofloxacin (OFL) as an internal standard and validate the same as per ICH guidelines. The chromatogram separation was achieved on Qualisil-5 BDS C8 column (250 mm × 4.6 mm, 5µm) column with mobile phase acetonitrile: water (pH 2.8 with TFA) in the composition of 84:16 v/v at a flow rate of 1 mL/min using PDA detector at 254 nm at ambient column temperature, keeping the injection volume 20 μL. The retention time of OFL, MNK, and EBA was observed to be 2.107 min, 2.517 min, and 3.819 min, respectively. All the criteria for the validation (linearity, accuracy, precision, and robustness) were observed to be within the acceptation range. The calibration plots were obtained between 5-60 µg/mL for MNK and 5-60 µg/mL for EBA with r2 values of 0.999 in each case. The recovery of MNK and EBA was found to be 98.99% and 99.40%, respectively with a % RSD of <2. This RP-HPLC method was found to be rapid, specific, precise, and accurate and can be used for the routine analysis of MNK and EBA in bulk as well as in tablet dosage form. The separation was complete with a shorter analysis time along with well good resolved peak.

Enhanced Extraction Efficiency of Flavonoids from Pyrus ussuriensis Leaves with Deep Eutectic Solvents

In this study, deep eutectic solvents (DESs) were synthesized using different ratios of choline chloride (CC) and dicarboxylic acids, and their eutectic temperatures were determined. The DES synthesized using CC and glutaric acid (GA), which showed a higher extraction efficiency than conventional solvents, was used for the extraction of flavonoid components from Pyrus ussuriensis leaves (PUL), and the extraction efficiency was evaluated using the response surface methodology. The flavonoid components rutin, hyperoside, and isoquercitrin were identified through high-performance liquid chromatography (HPLC), equipped with a Waters 2996 PDA detector, and HPLC mass spectrometry (LC-MS/MS) analyses. The optimum extraction was achieved at a temperature of 30 °C using DES in a concentration of 30.85 wt.% at a stirring speed of 1113 rpm and an extraction time of 1 h. The corresponding flavonoid content was 217.56 μg/mL. The results were verified by performing three reproducibility experiments, and a high significance, with a confidence range of 95%, was achieved. In addition, the PUL extracts exhibited appreciable antioxidant activity. The results showed that the extraction process using the DES based on CC and GA in a 1:1 molar ratio could effectively improve the yield of flavonoids from PUL.

A Validated Ultra Performance Liquid Chromatography Method for Simultaneous Estimation of Diacerein and Aceclofenac in Bulk and Pharmaceutical Formulation

A simple, exceptionally cost-effective, extremely accurate, quite precise and highly reproducible analytical method was developed and validated for simultaneous estimation of Diacerein and Aceclofenac in bulk and Pharmaceutical formulation. The new Ultra Performance Liquid Chromatography technique was developed. Method- The separation has been done on column ACQUITY UPLC BEH Shield C18 (50 x 2.1mm), 1.7µm (40°C temperature). The mobile phase contained Buffer and Acetonitrile (Buffer: ACN) (55:45 V/V).. The flow rate was set at 0.4ml/min, and detected at 268nm with PDA detector. Mobile phase was sonicated for 15 min. before use. 5μl of samples of standard stock solution and tablet solution were injected. Different trials were performed to separate diacerein and aceclofenac. The total run time of the detection was 4 min. The developed method was validated against different validation parameters. Results - The retention times were obtained at 1.762min. and 2.891 min. for Diacerein and Aceclofenac respectively. Accuracy study was observed in the range of 100.33% to 101.67% with less than 2% RSD. LOQ was found to be 2.98μg/ml and 5.9041μg/ml. similarly LOD was found to be 0.9841μg/ml and 1.9467μg/ml. for Diacerein and Aceclofenac respectively. Precision %RSD for intraday and interday were found to be 0.19 and 0.18 for Diacerein , 0.44 and 0.16 for Aceclofenac respectively. Linearity was found in the range of 2.5-17.5μg/ml and 5-35μg/ml for Diacerein and Aceclofenac respectively. The method was found robust by deliberate changes in the flow rate, ratio of mobile phase and detection wavelength. Conclusion-The method was found to be satisfactory and can be used successfully for determination of Diacerein and Aceclofenac simultaneously in bulk and pharmaceutical dosage form.

STABILITY INDICATING HPLC METHOD FOR ESTIMATION OF ELIGLUSTAT TARTRATE

For determination of eliglustat tartrate, a new, specific, simple, accurate (recovery) and precise stability indicating HPLC method has been developed and validated according to ICH Q2(R1) guidelines. The HPLC method was developed using acetonitrile: 0.1 % orthophosphoric acid 40:60 (V/V) as mobile phase, with pH of mobile phase adjusted to 3.0. The column used was HiQSil C-18 (250 mm x 4.6 mm, 5 μm) as stationary phase at a flow rate of 0.7 mL min-1. Retention time for eliglustat tartarate was found to be 5.9 min. The eluted compounds were detected using a PDA detector. The drug was subjected to stress testing as per ICH Q1A (R2) guideline. The degradation products did not interfere with the retention time of eliglustat. The calibration curve was found to be linear over a concentration range of 10-50 µg mL-1. For the calibration plots, R2 was found as 0.9995, indicating good linear relationship. The accuracy of the developed method was in the range of 99.87-100.62 %. The limit of detection of eliglustat was found to be 0.23 µg mL-1 and limit of quantification was 0.68 µg mL-1.

Validation of a simple HPLC method to quantify methotrexate concentrations in human plasma

Methotrexate (MTX) is a chemotherapy and immunosuppressive agent widely used to treat cancer, autoimmune diseases in children and adult patients, and ectopic pregnancy. However, MTX is highly toxic to the liver, kidney, and nervous system. This study aimed to quantify the concentration of MTX in human plasma using high-performance liquid chromatography (HPLC). MTX and its internal standard (para aminoacetophenone-PAPA) in plasma samples were extracted simultaneously with methanol. Sample purity was performed using the 1 cc OASIS HLB cartridges. Sample injection volume of 10 μL was analyzed on a Lichrocart Supersil 125-4 column C18 maintained at 40 °C on a Waters 2695 XE equipped with a PDA detector set at 303 nm. The mobile phase contained phosphate buffer (pH 6.0) and methanol at a ratio of 80:20 (v/v) and was maintained at a flow rate of 1 ml/min. The results showed that the total time of chromatographic analysis was 15 min. MTX and PAAP were found in the chromatograms at retention times of 2.3 and 5.2 min, respectively. The linear range of the MTX from 0.5 to 25 μg/mL. Intra-day and inter-day imprecision for MTX ranged from 3.42 to 8.128%. LLOQ of MTX was 0.5 μg/mL and the extraction effects were above 77%. In conclusion, we developed and validated a simple HPLC method to determine the MTX concentrations in human plasma.

A new stability indicating RP-UFLC method for the estimation of Etoricoxib in pharmaceutical dosage forms

Etoricoxib is a selective COX-2 inhibitor and used as a non-steroidal anti-inflammatory drug. A new validated stability indicating RP-UFLC method has been developed for the estimation of Etoricoxib in pharmaceutical dosage forms (Tablets). Shimadzu UFLC system (PDA detector) with Agilent C18 column was chosen for the chromatographic study with mobile phase Acetonitrile: water (50: 50) and flow rate 0.8 mL/min (UV detection at 230 nm). Beer-Lambert’s law was obeyed over a concentration range 0.1-100 µg/mL. The linear regression equation was found to be y = 82642x -13032 (R2 = 0.9998). The LOD and LOQ was found to be and 0.0291 and 0.0894 µg/mL respectively. Stress degradation studies were performed and the method was validated as per ICH guidelines. The proposed method is simple, precise, accurate and robust and can be applied for the quantification of Etoricoxib formulations.

Development and Validation of Stability Indicating UHPLC Method for Simultaneous Estimation of Ombitasvir, Paritaprevir and Ritonavir in Pharmaceutical Dosage Forms

The present research work was aimed to develop a validated UPLC method for simultaneous quantification of Ombitasvir, Paritaprevir and Ritonavir in bulk and pharmaceutical dosage forms. The analytes were successfully separated within 3 mins on waters SB C8 column using pH 4.0 phosphate buffer and acetonitrile in the ratio of 50:50v/v as mobile phase at a flow rate of 0.5ml/min with an injection volume of 0.5µl. The eluted analytes at 0.908, 1.190 and 1.739 min were detected at 250nm by PDA detector. The developed method was validated in compliance with ICH guidelines. The analytes under study obeyed beers law in the concentration range of 3.125 – 18.75µg/ml, 18.75 – 112.5µg/ml and 12.5 - 75µg/ml for Ombitasvir, Paritaprevir and Ritonavir respectively. The percentage recovery of analytes was found to be within 99-101% for the three analytes. The percentage RSD values of precision and robustness were within acceptable limits. The analytes were subjected to various stress conditions such as hydrolysis by acid, alkali and water, oxidation by hydrogen peroxide, exposure to High temperature and UV light, which enables analytes to degrade under these conditions. The proposed method was successful in separating and quantifying the compounds in the presence of degradants. Thus a specific, accurate and robust stability indicating method has been developed for simultaneous quantification of Ombitasvir, Paritaprevir and Ritonavir in their combined dosage form.

A NEW RELATED SUBSTANCES METHOD DEVELOPMENT AND VALIDATION OF TWO ANTI-CANCER DRUGS BY USING EFFECTIVE LIQUID CHROMATOGRAPHIC METHOD

Objective: The present study was aimed at developing and successively validating novel, simple, responsive and stable RP-HPLC method for the measurement of active pharmaceutical ingredients of mitomycin and fluorouracil and their related substances. Methods: Using the impurity-spiked solution, the chromatographic approach was optimized. The chromatographic method used Luna C18 column of dimensions 150x4.6 mn, 3.5 μm, using gradient elution with a mobile phase of acetonitrile and 0.1 percent orthophosphoric acid. A flow rate of 1 ml/min and a detector wavelength of 260 nm using the PDA detector was provided in the instrumental settings. Recovery, specificity, linearity, accuracy, robustness, ruggedness was determined as a part of method validation and the results were found to be within the acceptable range. Results: According to the ICH guidelines, the developed approach was validated. The calibration charts plotted were linear with a regression coefficient of R2>0.999. Conclusion: The method developed was found to be applicable to routine analysis and to be used for the measurement of active pharmaceutical ingredients (i. e, Mitomycin and Fluorouracil and its related impurities). Since there is no HPLC method reported in the literature for the estimation of Mitomycin, Fluorouracil and its related impurities; there is a need to develop quantitative methods under different conditions to achieve improvement in specificity, selectivity etc.

RAPID DETERMINATION OF CARBOPLATIN AND DOCETAXEL USİNG RP-HPLC WİTH PDA DETECTOR

Objective: In the current investigation, to separated and validate the cancer healing drugs (Carboplatin and Docetaxel) through the HPLC (e-2695) instrument containing a PDA detector. Methods: A simple, selective, validated and well-defined stability that shows isocratic RP-HPLC methodology for the quantitative determination of Carboplatin and Docetaxel. The chromatographic strategy utilized Symmetry C18 column of dimensions 150x4.6 mm, 3.5 micron, using isocratic elution with a mobile phase of acetonitrile and 0.1% ortho phosphoric acid (40:60). A flow rate of 1 ml/min and a detector wavelength of 225 nm utilizing the PDA detector were given in the instrumental settings. Recovery, specificity, linearity, accuracy, robustness, ruggedness were determined as a part of method validation and the results were found to be within the acceptable range. Validation of the proposed method was carried out according to an international conference on harmonization (ICH) guidelines. Results: LOD and LOQ for the two active ingredients were established with respect to test concentration. The calibration charts plotted were linear with a regression coefficient of R2>0.999. Conclusion: The proposed method to be fast, simple, feasible and affordable in assay condition. During stability tests, it can be used for routine analysis of production samples and to verify the quality of drug samples during stability studies.

ANALYTICAL METHOD DEVELOPMENT AND VALIDATION OF DEXMETHYLPHENIDATE AND SERDEXMETHYLPHENIDATE BY USING RP-HPLC IN BULK AND PHARMACEUTICAL DOSAGE FORM

Objective: The current investigation was pointed at developing and progressively validating novel, simple, responsive and stable RP-HPLC method for the simultaneous measurement of active pharmaceutical ingredients of Dexmethylphenidate and Serdexmethylphenidate. Methods: A simple, selective, validated and well-defined stability that shows isocratic RP-HPLC methodology for the simultaneous determination of Dexmethylphenidate and Serdexmethylphenidate. The chromatographic strategy utilized inertsil ODS column of dimensions 250x4.6 mm, 5 µ, using isocratic elution with a mobile phase of acetonitrile and 0.1% orthophosphoric acid (70:30). A flow rate of 1 ml/min and a detector wavelength of 262 nm utilizing the PDA detector were given in the instrumental settings. Recovery, specificity, linearity, accuracy, robustness, ruggedness were determined as a part of method validation and the results were found to be within the acceptable range. Validation of the proposed method was carried out according to an international conference on harmonization (ICH) guidelines. Results: LOD and LOQ for the active ingredient were established with respect to test concentration. The calibration chart plotted was linear with a regression coefficient of R2>0.999, which means the linearity was within the limit. Conclusion: The proposed method to be fast, simple, feasible and affordable in assay condition. During stability tests, it can be used for routine analysis of production samples and to verify the quality of drug samples during stability studies.

Detection and Dietary Exposure Assessment of Fluoroquinolones Residues in Chicken Meat from the Districts of Malang and Blitar, Indonesia

The purpose of this study was to determine the presence of fluoroquinolones (enrofloxacin and ciprofloxacin) residues in fresh chicken meat and evaluate its consumption risk to the adult population in Indonesia. A total of 55 fresh chicken-meat samples were collected from Districts of Malang and Blitar, East Java Province, Indonesia, in April 2017. Detections of enrofloxacin and ciprofloxacin were carried out using high-performance liquid chromatography equipped with a PDA detector. It was found that ciprofloxacin was detected with a frequency of 67.3% at a maximum concentration of 275.00 ng/g. Enrofloxacin was detected with a frequency of 41.8% at a maximum concentration of 242.40 ng/g, or totally as a sum of enrofloxacin and ciprofloxacin residues detected in 76.4% samples at a maximum concentration of 367.50 ng/g. The estimated dietary intakes of ciprofloxacin and enrofloxacin were 44.90 ng/kg body weight/day and 7.91 ng/kg body weight/day, respectively, resulting in the hazard indexes of 0.0063 and 0.0013 for the consumptions of ciprofloxacin and enrofloxacin residues in chicken meat. Therefore, the risk associated with the consumption of ciprofloxacin and enrofloxacin residues in chicken meat by the adult population in Indonesia was considered negligible.

A Novel Truncated DNAzyme Modified Paper Analytical Device for Point-of-Care Test of Copper Ions in Natural Waters

On-site determination of trace copper ions in natural waters is of great significance to environmental monitoring, and how to develop accurate and specific point-of-care test methods is one critical issue. In the study, a paper-based analytical device (PAD) being modified with a new truncated DNAzyme (CLICK-T, which was derived from a reported DNAzyme-CLICK-17) was developed for Cu ions detection. The detection mechanism was based on Cu(II)-catalyzed azide-alkyne cycloaddition (Cu(II)AAC) reaction. It can directly conduct on-site analysis of Cu(II) ions based on fluorescent signals detected using a mobile phone. In the assay, the CLICK-T was firstly modified on the PADs. Then, water samples containing Cu ions mixed with 3-azido-7-hydroxycoumarin and 3-butyn-1-ol were instantly dripped on PADs and incubated for 20 min. Finally, the PADs were excited at 365 nm and emitted fluorescence which could be analyzed on site using smart phones. The Cu(II) concentration could be quantified through RGB analysis with the aid of iPhone APP software. The limit of detection is 0.1 µM by the naked eye due to the fact that CLICK-T exhibited a good catalytic effect on Cu(II)AAC. The Cu(II) concentration could also be directly detected without using reductant, such as ascorbic acid, which is prone to be oxidized in air. This simplifies the PDA detection process improves its efficiency. The PAD is convenient for the on-site analysis of Cu ions in natural waters.

Box–Behnken experimental design for optimizing the HPLC method to determine hydrochlorothiazide in pharmaceutical formulations and biological fluid

An isocratic HPLC method was developed to quantify hydrochlorothiazide (HCT) and its impurities (A, B, C). Response surface methodology combined Box-Behnken design was applied to optimize the effects of four independent factors; pH (2–4), acetonitrile (2–15%), methanol (2–15%) and flow rate (0.7–1.3 mL min−1) against the response. The current investigation aimed to choose the utmost significant factors with the maximum influences of chromatographic separation: resolution, tailing factor, and the number of theoretical plates. Statistical analysis of variance (ANOVA) indicated the best conditions for separating the compounds and the most influential parameters. The plots (contour, 3D surface and perturbation) described the statistically significant parameters quantitatively and their interactions. The experimentally derived RSM model was validated using a t-test with observed R2 value, adjusted R2, predicted R2 and F-values, indicating that the developed model was significant. The proposed LC was combined with a PDA detector and detected at 210 nm. The HCT highest separation was achieved on the ODS Hypersil C18 (250 mm × 4.6 mm, 5 μm) column using the following conditions: pH (3.497), acetonitrile (10.6%), methanol (16.2%), flow rate 1 mL/min. The method validated was precise and linear in 1.25–12.75 µg mL−1. The validated method's value of LOD & LOQ was 1.09 and 3.33 µg mL−1, respectively. Youden and Steiner’s factorial design with typical and alternative conditions were performed to verify its robustness study. The % RSD values were within the accepted range of ICH guidelines. Therefore, the proposed method can be applied for routine analysis of HCT and its impurities in pharmaceutical formulation and biological fluid for routine quality control sample analysis.

Development and validation of a stability indicating UPLC method for determination of Darolutamide in its tablet formulation

Darolutamide is an orally active, second generation non-steroidal anti-androgen. The objective of this study was to develop a simple and fast stability indicating method for the determination of Darolutamide in bulk and tablets. Darolutamide was eluted on a Zorbax SB-C18 column (100X2.1mmX1.8µ) with a mobile phase of 8mM ammonium acetate, pH: 5.4: acetonitrile (66:34 v / v) in isocratic mode at a flow rate of 0.4 ml / min. The analyte was quantified using a 272 nm PDA detector. The chromatograms of darolutamide obtained with this method showed a well resolved retention time at 0.83 min of its excipients and degradation products. The area of the peak with respect to the concentration calibration curves, which were linear from 70 to 210 µg / ml, had a regression coefficient (r2) greater than 0.999. The detection limit (LOD) and the limit of quantification (LOQ) were found at 1.80 and 6.01 µg/mL respectively. Accuracy and precision have been determined and perfectly matched to the ICH standards. The study showed that the proposed UPLC method was simple, fast, robust and reproducible, which can be used for the evaluation of the purity and stability of the drug without interference from excipients or decomposition products of active pharmaceutical ingredients.

Validated Stability-Indicating Assay UHPLC Method for Simultaneous Estimation of Doravirine, Lamivudine and Tenofovir Disoproxil Fumarate in Pure Material and Pharmaceutical Matrix

An efficient, robust, and specific stability-indicating UHPLC assay method was acquainted for simultaneous determination of antiretroviral agents doravirine (DOV), lamivudine (LVD), and tenofovir disoproxil fumarate (TDF). The determination of cited agents was performed on UPLC system using UPLC BEH C18 (150 mm × 2.1 mm) with 1.7 µm particle size column at ambient temperature using a solvent system in a proportion of (60:40 % v/v) acetonitrile: potassium dihydrogen orthophosphate buffer; pH 4.5 ± 0.2 was adjusted with 0.1 % OPA. The PDA detector was subjected to a wavelength of 235 nm. DOV, LVD, and TDF were experienced in various stress procedures of forced degradation experiments, as recommended by the ICH, to assess the established method's stability-indicating practicability. Using the optimized procedure, selected agents were successfully distinguished from the peaks of their respective degradation products. Furthermore, the calibration curves for DOV, LVD, and TDF in over wide concentration ranges of 2–12μg/mL, 5–30μg/mL, and 5–30μg/mL, respectively, with determination coefficients (r2) of 0.997, 0.9994, and 0.9994. The method validation assays had less than 2 % relative standard deviations for accuracy, precision, repeatability, and robustness.