Ultra-performance Liquid Chromatography Method Research Articles

A Novel Ultra Performance Liquid Chromatographic Method for the Estimation of Lercanidipine in Bulk and Tablet Dosage Form

Aim: In this present study an accurate reverse phase ultra-performance liquid chromatography (RP-UPLC) method has been developed, validated and applied to stability indicating studies to determine Lercanidipine HCL in bulk and marketed dosage form.
 Methods: Optimized chromatographic conditions were achieved by using Waters Acquity BEH C18 (2.1 x 50mm, 1.7m) UPLC column. Empower 2 is a software, dihydrogen Orthophosphate Buffer : Methanol (40 : 60)  as eluent at flow rate 0.3 ml/min. PDA detection was performed at 254nm.
 Results: The developed method was validated and stability study was conducted as per ICH guidelines. The retention time was found at 0.503 min. The method shows linearity over a range of 1 μg/ml to 60 μg /ml with the obtained correlation coefficient is 0.999. The LOD and LOQ values were found 0.025 and 0.05 μg /ml. The acidic and peroxide stressed study shows more degradation of 6.23% and 3.03%.
 Conclusion: The present developed method was found stability indicating, reliable, validated method was applied for the routine analysis of lercanidipine in bulk drug and the pharmaceutical formulations.

ANALYTICAL METHOD DEVELOPMENT AND VALIDATION OF COMBINATION OF ANTI-ASTHMATIC DRUGS MONTELUKAST AND DOXOFYLLINE

For qualitative and quantitative analysis, various analytical techniques are available such as Ultraviolet (UV) Spectrophotometry, High-performance liquid chromatography (HPLC), High-performance thin layer chromatography (HPTLC). As per literature survey, there are some UV, HPLC, Ultra-Performance Liquid Chromatography (UPLC) and HPTLC analytical methods are developed for Montelukast and Doxofylline individually and in a combination with other drugs too, since yet there are no significant stability studies indicating HPLC method reported for Montelukast and Doxofylline combinations. In the current study, the HPLC method is developed and validated for simultaneous quantitative estimations of Montelukast and Doxofylline. These present techniques are more efficient and sensitive as compared to other analytical techniques.

ANALYTICAL METHOD DEVELOPMENT AND VALIDATION OF COMBINATION OF ANTI-ASTHMATIC DRUGS MONTELUKAST AND DOXOFYLLINE

For qualitative and quantitative analysis, various analytical techniques are available such as Ultraviolet (UV) Spectrophotometry, High-performance liquid chromatography (HPLC), High-performance thin layer chromatography (HPTLC). As per literature survey, there are some UV, HPLC, Ultra-Performance Liquid Chromatography (UPLC) and HPTLC analytical methods are developed for Montelukast and Doxofylline individually and in a combination with other drugs too, since yet there are no significant stability studies indicating HPLC method reported for Montelukast and Doxofylline combinations. In the current study, the HPLC method is developed and validated for simultaneous quantitative estimations of Montelukast and Doxofylline. These present techniques are more efficient and sensitive as compared to other analytical techniques.

Development and Validation of Ultra Performance Liquid Chromatographic Method Simultaneous Estimation of Aspirin and Ticlopidine Hydrochloride in Pharmaceutical Formulation

Objective: The combined dose tablet formulation containing aspirin and ticlopidine hydrochloride is used to reduce the formation of harmful blood clots in blood vessels which helps in preventing a heart attack or stroke in people with heart disease. The objective of the present work was to develop an accurate, precise, economical and less time consuming UPLC method and subsequently validate the method as per ICH guidelines, for routine quality control of combined dose tablet formulation containing above mentioned drug.
 Methods: The present work describes development and validation of ultra performance liquid chromatographic method for simultaneous quantitation of aspirin and ticlopidine hydrochloride in tablets. The chromatographic separation was carried out using Supelcosil LC-18 (3.3 cm × 4.6 mm × 3 µm) column using mixture of Potassium Phosphate buffer (0.01M) and Acetonitrile (20:80 v/v) as mobile phase with a flow rate of 0.6 ml per minute, total run time was 3 minutes. The detection and quantitation of chromatographic peaks was carried out at 230 nm.
 Results: The retention time for aspirin (ASP) and ticlopidine hydrochloride (TPH) was 0.529 minutes and 1.530 minutes, respectively. The linearity of detector response was observed in the concentration range of 20 – 60 µg/ml and 50-150 µg/ml for ASP and TPH, respectively. The LOD and LOQ for ASP and TPH was found to be 0.399 & 1.209 and 3.385 & 10.260, respectively. The accuracy of the method was found in the range of 99.92 – 100.58 % and 98.91 – 100.52 for ASP and TPH, respectively. The relative standard deviation for intra-day and inter-day precision studies was below 2 % indicating that the method is precise. The robustness of the proposed method was evaluated by varying the chromatographic parameters and the effect of these changes on retention time and tailing factor was studied. The % RSD for retention time and tailing factor was below 2 % indicating that the method is robust. The forced degradation studies were carried out to evaluate the specificity of the method. As the method was able to quantitate ASP and TPH selectively in presence of degradation products, the method was found to be specific. As the results of validation studies were within standard limits, the method was successfully applied for simultaneous estimation of ASP and TPH in marketed tablet formulation.
 Conclusion: The method has distinct advantages over reported UV and HPLC methods and hence the developed UPLC method can be used for routine quality control of Aspirin and Ticlopidine hydrochloride combined tablet formulation.

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

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

Potential value and chemical characterization of gut microbiota derived nitrogen containing metabolites in feces from Periplaneta americana (L.) at different growth stages

The American cockroach, Periplaneta americana (L.), is able to highly survive in various complicated environments around the globe, and often considered as a pest. In contrast, billions of P. americana have been massively reared in China and extensively used as a medicinal insect, due to its function for preventing and treating ulceration and heart failure. Considering the possibility that microbiota-derived metabolites could be an effective source to identify promising candidate drugs, we attempted to establish a rapid method for simultaneous determination of gut microbiota metabolites from medicinal insects. In this study, network pharmacology approach and ultra-performance liquid chromatography (UPLC) technique were employed to reveal the potential pharmacological activity and dynamics variation of nitrogen-containing metabolites (NCMs) originated from the gut microbiota of breeding P. americana at different growth stages. A metabolites-targets-diseases network showed that NCMs are likely to treat diseases such as ulceration and cancer. The analysis of NCMs' content with the growth pattern of P. americana indicated that the content of NCMs declined with P. americana aging. Both principal component analysis and orthogonal partial least squares discriminant analysis suggested that 8-hydroxy-2-quinolinecarboxylic acid and 8-hydroxy-3,4-dihydro-2(1H)-quinolinone are the potential differential metabolic markers for discriminating between nymphs and adults of P. americana. Moreover, the developed UPLC method showed an excellent linearity (R2 > 0.999), repeatability (RSD < 2.6%), intra- and inter-day precisions (RSD < 2.2%), and recovery (95.5%–99.0%). Collectively, the study provides a valuable strategy for analyzing gut microbiota metabolites from insects and demonstrates the prospects for discovering novel drug candidates from the feces of P. americana.

UHPLC With On-Line Coupled Biochemical Detection for High Throughput Screening of Acetylcholinesterase Inhibitors in Coptidis Rhizoma and Cortex Phellodendri.

We developed a new on-line method of ultra-performance liquid chromatography coupled with biochemical detection (UHPLC-BCD) to screen acetylcholinesterase (AChE) inhibitors in complex matrixes. Chromatography separation was performed using an Xtimate UHPLC C18 column (100mm × 2.1mm, 1.8μm) and a gradient elution with methanol-0.1% formic acid at a flow rate of 0.08mL/min. The BCD was based on a colorimetric method using Ellman's reagent, and the detection wavelength was at 405nm. Galanthamine was used as a positive reference to validate the methodology. The detection and quantitation limits of the UHPLC-BCD method were 0.018 and 0.060μg, respectively. A functional equation was generated in terms of the negative peak area (X) and galanthamine concentration (Y, μg/mL). The regression equation was Y = 0.0028X2 + 0.4574X + 50.7776, R2 = 0.9993. UHPLC-fourier-transform mass spectrometry detection results revealed that five alkaloids showed obvious AChE inhibitory activities including coptisin, epiberberine, jatrorrhizine, berberine and palmatine. The relative AChE inhibitory activities of jatrorrhizine, berberine and palmatine in the Coptidis Rhizoma sample were equal to that of 257.0, 2355 and 283.9μg/mL of galanthamine, respectively. This work demonstrated that the UHPLC-BCD method was convenient and feasible, and could be widely used for the screening and activity evaluation of the bioactive components in the complex extracts.

A Rapid, Reliable RP-UPLC Method for Large-Scale Analysis of Wheat HMW-GS Alleles.

High-molecular-weight glutenin subunits (HMW-GS) account for only 10% of total wheat storage proteins, but play an important role in the processing quality of wheat flour. Therefore, identifying HMW-GS alleles associated with good end-use quality provides important information for wheat breeders. To rapidly, accurately and reproducibly identify HMW-GS, we established an optimized reversed-phase ultra-performance liquid chromatography (RP-UPLC) method. Separation parameters were optimized using an ACQUITY UPLC Protein BEH C4 column and stepwise ACN gradient, and the separation patterns and retention times (RTs) of 22 subunits were comparatively analyzed in 16 standard wheat cultivars. All HMW-GS proteins were well separated within about 5.5 min, and all analyses were complete within 12 min. We distinguished the 16 subunits based on RT, although three subunits in 1Bx (1Bx7/1Bx7OE and 1Bx17) and three subunits in 1By (1By8*, 1By9 and 1By15) had overlapping RTs; these were differentiated by SDS-PAGE. To distinguish 1Bx7 and 1Bx7OE, which differ in protein abundance, RP-UPLC was combined with PCR analysis of DNA junction markers. The optimized method was successfully applied to determine HMW-GS alleles in a large collection of bread wheat germplasm (1787 lines). This protocol is an appropriate option for selecting lines harboring favorable HMW-GS alleles in wheat breeding.

Quantification and Stability Indicating UPLC Method Development and Validation of Acalabrutinib in Bulk and Pharmaceutical Dosage Form

Acalabrutinib (ABN) is a Bruton tyrosine kinase inhibitor used to treat mantle cell lymphoma, chronic lymphocytic leukemia and small lymphocytic lymphoma. It has been used in the treatment of Hodgkin lymphoma, multiple myeloma and ovarian cancer. It is available in capsule dosage form, usually prescribed twice a day. The objective of the present study describes the ultra-performance liquid chromatography (UPLC) method development and validation for the estimation of the ABN in Capsule dosage form by following ICH guidelines because no methods were reported in this category. The column and Mobile phase were selected based on trial and error methods. For the estimation, the chromatogram BEH C18 (50 mm x 2.1 mm, 1.7µm) column was run through with Mobile phase 0.01N KH2PO4 : Methanol in the ratio of 50:50 at a flow rate of 0.3 ml/min. Temperature was maintained at 30°C. Optimized wavelength selected for the separation was 234nm. Retention time was achieved 1.148minute in optimized chromatogram. Theoretical plate count and tailing factor were obtained “as per recommendations of ICH limits”. The % RSD precision obtained was 0.7% and Intermediate precision obtained was 0.7% as the limit of Precision was less than 2. %Recovery obtained for marketed formulation was 99.23%. LOD, LOQ values obtained from the regression equation (y=9128.5x + 14854) of ABN were 0.18µg/ml and 0.55µg/ml respectively. Proposed method was linear over the concentration range25-150µg/ml. Different degradation studies (acid, alkali, oxidation, thermal, UV, water) were performed and all these samples passed the limits of degradation. Retention time and run time was decreased, so the method developed was simple and economical that can be adopted in regular quality control tests in Industries.

A Novel UPLC Method for Simultaneous Estimation of Ertugliflozin and Sitagliptin in Bulk and Tablet Dosage Form

Aim: The proposed study aimed to develop a novel ultra-performance liquid chromatography (UPLC) method for the estimation of Ertugliflozin and Sitagliptin in Bulk and Tablet dosage form and validate the method in accordance with the International Conference on Harmonization guidelines. Methods: The optimized conditions for the developed UPLC method are Acquity UPLC HIBRA C18 (100mm × 2.1mm, 1.8µ) column maintained at 30°C with a mobile phase consisting of Buffer (0.01N sodium hydrogen phosphate) pH adjusted to 4.0 with dil. orthophosphoric acid: Acetonitrile in the ratio of 60:40%v/v on isocratic mode at a flow rate of 0.3mL/min. Results and conclusion: The sample was detected at 220nm. The retention time for Ertugliflozin and Sitagliptin was deemed at 1.873min and 1.260min. The developed method was validated for accuracy, precision, specificity, ruggedness, robustness, and solution stability. The method obeyed Beer’s law in the concentration range of 3.75µg/mL to 22.5µg/mL for Ertugliflozin and 25µg/mL to 150µg/mL for Sitagliptin with a correlation coefficient of 0.999 for Ertugliflozin and Sitagliptin respectively. Forced degradation studies were conducted by exposing the drug solution to numerous stress conditions such as acidic, basic, peroxide, neutral, photolytic, and thermal conditions. The net degradation was considered within the limits, indicating that the drug is stable in stressed conditions. The developed method for the estimation of Ertugliflozin and Sitagliptin can be utilized for the routine analysis of Pharmaceutical dosage form.

A Stability-Indicating Ultra Performance Liquid Chromato-Graphic (UPLC) Method for the Determination of a Mycophenolic Acid-Curcumin Conjugate and Its Applications to Chemical Kinetic Studies.

A simple, precise, and accurate reversed-phase ultra-performance liquid chromatographic (UPLC) method was developed and validated for the determination of a mycophenolic acid-curcumin (MPA-CUR) conjugate in buffer solutions. Chromatographic separation was performed on a C18 column (2.1 × 50 mm id, 1.7 µm) with a gradient elution system of water and acetonitrile, each containing 0.1% formic acid, at a flow rate of 0.6 mL/min. The column temperature was controlled at 33 °C. The compounds were detected simultaneously at the maximum wavelengths of mycophenolic acid (MPA), 254 nm, and curcumin (CUR), or MPA-CUR, at 420 nm. The developed method was validated according to the ICH Q2(R1) guidelines. The linear calibration curves of the assay ranged from 0.10 to 25 μg/mL (r2 ≥ 0.995, 1/x2 weighting factor), with a limit of detection and a limit of quantitation of 0.04 and 0.10 μg/mL, respectively. The accuracy and precision of the developed method were 98.4–101.6%, with %CV < 2.53%. The main impurities from the specificity test were found to be MPA and CUR. Other validation parameters, including robustness and solution stability, were acceptable under the validation criteria. Forced degradation studies were conducted under hydrolytic (acidic and alkaline), oxidative, thermal, and photolytic stress conditions. MPA-CUR was well separated from MPA, CUR, and other unknown degradation products. The validated method was successfully applied in chemical kinetic studies of MPA-CUR in different buffer solutions.

Ultra-Performance Liquid Chromatographic and Densitometric Methods for Sensitive Determination of Xipamide and Triamterene in Pure and Pharmaceutical Dosage Forms.

Validated ultra-performance liquid chromatography (UPLC) and thin-layer chromatography (TLC) densitometric methods were prescribed for determination of antihypertensive components. To establish and validate rapid and accurate UPLC and TLC densitometric methods for determination of Xipamide and Triamterene in pure and dosage forms. The first method, UPLC, depended on using an Agilent Zorbax Eclipse Plus C8 (50 mm × 2.1 mm, 1.8 μm) column, a mobile phase composed of acetonitrile-water (70 + 30, v/v) adjusted by acetic acid to obtain pH 3, 0.2 mL/min flow rate, and UV detection at 231.4 nm. The second method was a TLC densitometric method. Separation was achieved by using toluene-methanol-ethyl chloride-acetic acid (7 + 2 + 1 + 0.2, v/v/v) as the mobile phase, pre coated silica gel plates as the stationary phase, and UV detection at 300.0 nm. The obtained results were validated and statistically compared with official and reported methods. The obtained results showed high accuracy and reproducible results with excellent mean recoveries for both drugs. The UPLC method showed shorter retention time for both Xipamide (0.88 min) and Triamterene (0.63 min), a lower detection limit of less than 0.055 µg/mL for both drugs with high selectivity, decreased injection volume (1 µL), and a lower flow rate than any HPLC method. Both proposed methods were sensitive, selective, and effectively applied to pure and dosage forms (Epitens®). Unprecedented sensitive, rapid, and reproducible UPLC and TLC methods were developed for selective determination of mixtures of Xipamide and Triamterene, with LOD os less than 0.076 µg/mL for both drugs.

Analytical Method Development and Validation for the Analysis of Nepafenac and its related substances using Ultra Performance Liquid Chromatography

A novel, economic and time-efficient reverse-phase ultra-performance liquid chromatographic (RP-UPLC) method has been developed for the analysis of Nepafenac in the presence of both impurities and degradation products generated by forced degradation. When Nepafenac was subjected to acid hydrolysis, oxidative, base hydrolysis, photolytic, and thermal stress, observed degradation only in oxidative and base hydrolysis. The drug was found to be stable to other stress conditions. Various method development trails were performed for the separation of drug from impurities. However, best chromatographic separation was achieved on a Waters Acquity CSHC18, 100mm x 2.1mm, 1.7µ particle size column, UV detection at 245nm, a gradient elution of Ammonium formate (pH 4.0), mixture of organic solvents (Acetonitrile, Methanol) as mobile phase for drug, its impurities and it was captured. The method was validated for specificity, precision, linearity, accuracy, robustness and can be used in quality control during manufacture and for assessment of the stability samples of Nepafenac. Total elution time was about 6.5 min and equilibration time of about 1.5 min which allowed analysis of more than 100 samples per day. The analytical method discussed in United states Pharmacopoeia was pH sensitive and compatible to LC-MS analysis.

Effect of Single-Dose and Short-Term Administration of Si Jun Zi Tang on the Pharmacokinetics of Gefitinib in Rats.

Background Si Jun Zi Tang (SJZ), a four-herb Chinese medicine formula that has been described for approximately one thousand years, is often prescribed for cancer patients as a complementary therapy in China. However, the mechanism by which Si Jun Zi Tang enhances the efficacy of gefitinib is unclear. Methods We investigated how Si Jun Zi Tang affected the pharmacokinetics of gefitinib in rats. A rapid, specific, and reliable ultra-performance liquid chromatography method with mass spectrometry was established to determine the plasma concentration of gefitinib. Results The results showed that a single intragastrically administered dose of Si Jun Zi Tang increased the pharmacokinetic parameters of gefitinib (Cmax, 3156.13 μg/L; A UC, 46281.5 μg/L/h) by 3 folds in rats compared with the administration of gefitinib alone (Cmax, 1352.07 μg/L; AUC, 11823.7 μg/L/h). Si Jun Zi Tang could also alter the pharmacokinetics of gefitinib by prolonging the time to reach Cmax. Conclusions Potential pharmacokinetic interactions between gefitinib and SJZ were evaluated, and SJZ extended Tmax and T1/2 and increased the Cmax and AUC of gefitinib. Long-term administration of gefitinib in combination with Si Jun Zi Tang would improve the efficacy of gefitinib.

Research Note: Study on the residue depletion of febrifugine and isofebrifugine in broiler chicken

In this study, 105 broiler chickens were fed with dietary feeds containing different contents of Dichroae Radix extract for 10 consecutive days. Then the residue depletions of its main alkaloids (febrifugine and isofebrifugine) in muscle, kidney and liver samples at different withdrawal times were determined by an ultra-performance liquid chromatography method. Results showed that the 2 alkaloids were mainly at tissue-bound formation. At withdrawal period of 0 d, their concentrations in all samples were high but decreased rapidly after 1 day of cessation (35–91%). After 5 to 7 days of cessation, their residues in muscle and kidney were not detectable, and after at least 10 days of cessation they were not detectable in liver. These results indicated that an appropriate withdrawal time for Dichroae Radix preparation was required if it is licensed as a new drug, and the best target tissue for monitoring its residue was liver.

Development and Validation of UPLC-MS/MS Method for the determination of Rivaroxaban in human plasma using Liquid-liquid extraction

A simple, sensitive, and selective ultra-performance liquid chromatographic (UPLC) method with mass spectrometric (UPLC-MS/MS) detection was developed for the determination of Rivaroxaban in human plasma sample. After a simple protein-precipitation by acetonitrile, the post-treatment samples were separated on a UPLC Bridged Ethyl Hybrid (BEH) C-18 column with 0.2% (v/v) formic acid in water: acetonitrile (60:40, v/v) as a mobile phase and analyzed in positive ion mode. The method developed was validated in human plasma with a daily working range of 2.02–997.72ng/mL with correlation coefficient, r2=0.999936. The method proved to be accurate (recovery, 97.0–107.95%), precise (2.21-7.21%), rapid (run time 2.5 min) and specific. In conclusion, the present validated method could be applied for pharmacokinetic study and bioequivalence testing of Rivaroxaban products.

Assay of tirofiban and identification of oxidative impurity in aqueous injection by using UPLC-PDA/QDa detectors

The basic objective of this study is to propose a short, reliable, mass compatible ultra-performance liquid chromatography (UPLC) method to confirm the identity of impurities and to estimate the assay and purity of Tirofiban simultaneously in aqueous injection (5mg/100mL bag). Aqueous formulations are susceptible to oxidation, hence the possible oxidative degradation impurities of Tirofiban were studied in this experiment by using UPLC coupled with photodiode array/Quadrupole Dalton Analyzer (PDA/QDa) detectors. The required separations were achieved in the column: ACQUITY HSS T3 (100×2.1) mm, 1.7μm, operated at 30°C by using 0.02% Triethyl amine (TEA) in water, pH 2.8 with formic acid as solution-A and 0.1% formic acid in 9:1 acetonitrile, water as solution-B. Binary gradient flow is delivered at the rate of 0.5mL/min and the detection of impurities specifically carried out at 227nm using empower3 software. RP-UPLC/PDA with QDa detector was used for the experiment. The method was linear and accurate from the concentrations: 0.04 to 0.38μg/mL for impurity-A and 0.04 to 75μg/mL for Tirofiban. The major unknown degradation impurity generated during the oxidative degradation has been identified as N-oxide derivative (Impurity-B) [(M+H)+ 455.1] by using QDa detector operated in an electro spray positive ion mode by applying a voltage of 0.8kV. This method was further validated as per ICH Q2 (R2) guidelines. Hence, the proposed method is said to be a fast, sensitive and comprehensive technique, which could give a clear idea about the assay and impurity profile of Tirofiban injection.

Drying methodology effect on the phenolic content, antioxidant activity of Myrtus communis L. leaves ethanol extracts and soybean oil oxidative stability

In this study, different drying methodologies (convective air, oven and microwave) of Myrtus communis L. (M. communis L.) leaves were conducted to investigate their effects on the levels of phenolic compounds, antioxidant capacity of ethanolic extracts (EEs) as well as the soybean oil oxidative stability. Drying methodology significantly influenced the extractability of phenolic compounds. Microwave drying led to an increase in the amounts of total phenols, flavonoids and proanthocyanidins followed by oven drying at 70 °C. Higher temperature of drying (100 and 120 °C) led to a significant reduction of their amounts (p < 0.05). An ultra-performance liquid chromatography method combined with high resolution mass spectroscopic detection was used to analyze the phenolic fraction of extracts. Higher amounts of the identified compounds were observed when leaves were heat treated. Furthermore, the evaluation of the antioxidant activity showed that the studied extracts possess in general high antioxidant capacities, significantly dependent on the employed drying methodology. The incorporation of the different extracts at 200 ppm in soybean oil showed that its oxidative stability was significantly improved. Extracts from leaves treated with microwave (EE_MW) and at 70 °C (EE_70) have better effect than BHT. The results of the present study suggest that microwave drying could be useful to enhance the extractability of phenolic compounds and the antioxidant capacity of M. communis L. leaf extract.

Development and validation of stability-indicating UPLC method for the determination of gliclazide and its impurities in pharmaceutical dosage forms

BackgroundFor the determination of gliclazide and its three potential impurities quantitatively, the development of a stability-indicating, accurate, simple, and fast, Ultra-Performance Liquid Chromatography (UPLC) method was done.ResultsOn Acquity CSH 18 column (50 mm×2.1 mm, 1.7 μ) separation was achieved by the isocratic elution mode using mobile phase (5 mM ammonium acetate buffer of pH 4 and 10% ammonium acetate buffer + 90% acetonitrile, 65/35 v/v). In total, 0.7 mL−1 was the chosen flow rate and UV detection was carried out at 227 nm.ConclusionBy analyzing forced degradation products of the sample, the stability-indicating characteristic of the developed method was proved where the separation of the products of degradation from analyte peak was seen along with spectral purity of gliclazide. Validation of the developed UPLC method was done as per the guidelines of the International Conference on Harmonization in terms of system suitability, precision, accuracy, specificity, sensitivity, linearity, and robustness.

Development and Validation of Ultra Performance Liquid Chromatography Method for the Estimation of Etodolac in Bulk and Its Application to Marketed Dosage Form

Development and Validation of Ultra Performance Liquid Chromatography Method for the Estimation of Etodolac in Bulk and Its Application to Marketed Dosage Form