Rapid Reversed-phase High-performance Liquid Chromatography Method Research Articles

A Rapid, Validated RP-HPLC Method for the Determination of Seven Volatile N-Nitrosamines in Meat

The present work reports a rapid reversed-phase high-performance liquid chromatography (RP-HPLC) method for the determination of seven volatile N-nitrosamines namely N-nitrosodimethylamine (NDMA), N-nitrosomethylethylamine (NMEA), N-nitrosodiethylamine (NDEA), N-nitrosodiproylamine (NDPA), N-nitrosodi butylamine (NDBA), N-nitrosopiperidine (NPIP) and N-nitrosopyrrolidine (NPYR) for monitoring food safety. A strategic experimental approach was implemented for the method development. The desired chromatographic separation was achieved on a Symmetry C18 (4.6 × 150 mm, 5 μm) column using gradient elution. The optimized mobile phase consisted of the 10 mM ammonium hydroxide pH = 8.9 and acetonitrile. The eluted compounds were monitored at 231 nm wavelength using spectrophotometric detector. The developed method separated seven compounds from each other within a run time of 10 min. The method is effective for the determination of presence of these carcinogenic compounds. The average extraction recovery of seven nitrosamines was found 84.5%; the precision of method was found less than 2.7% and accuracy was found between 95%-102.5%. The assay could be applied in food monitoring safety.

Development and Validation of RP-HPLC Method for Azilsartan Medoxomil Potassium Quantitation in Human Plasma by Solid Phase Extraction Procedure

Simple and rapid reverse phase high-performance liquid chromatography (RP-HPLC) method was developed and validated using solid phase extraction (SPE) technique for the determination of Azilsartan Medoxomil Potassium (AMP) in human plasma; detection was carried out by photo diode array detector. Chromatographic separation of the analyte AMP was achieved within 7.5 min by Waters symmetry C18 (4.6 × 250 mm, 5 µm) column, mobile phase was 25 mM ammonium acetate buffer (pH 5.5): acetonitrile 55 : 45 v/v, flow rate was 1.0 mL/min, and the detection was carried out at 254 nm. Calibration curve was linear (r2 > 0.9985) in the range of 1.0–9.0 µg/mL, limit of detection (LOD) and limit of quantitation (LOQ) were 0.150 µg/mL and 0.400 µg/mL, respectively, and intra- and interday deviations were between 1.53–8.41% and 1.78–4.59%, respectively. The overall mean recovery of AMP was 92.35%. No any endogenous constituents were found to interfere at retention time of the analyte. This new RP-HPLC method was successfully validated and may be applied to conduct bioavailability and bioequivalence studies of AMP.

A Rapid Validated RP-HPLC Method for the Simultaneous Determination of Cleaning Validation and Cross Contamination of 12 Beta-Lactam Compounds

The present work reports a rapid reversed-phase high-performance liquid chromatography (RP-HPLC) method for the simultaneous determination of 12 beta-lactam components for cleaning validation and cross-contamination. A strategic experimental approach was implemented for the method development. The desired chromatographic separation was achieved on a Symmetry C18 (4.6 X 75 mm, 3.5 μm) column using gradient elution. The optimized mobile phase consisted of the buffer tetrabutylammonium hydroxide pH-6.8 and acetonitrile. The eluted compounds were monitored at 215 nm and 254 nm wavelength using a photodiode array detector. The developed method separated 12-beta-lactam compounds from each other within a run time of 50 min. The method is effective for the determination of cross-contamination of penicillin and cephalosporin production blocks. The present method is specific and a lower limit of quantification was determined on the basis of the signal-to-noise ratio method; it is 1 μg/mL for all components. The developed RP-HPLC method was validated according to the International Conference on Harmonization (ICH) guidelines.

Development and validation of a stability indicating RP-HPLC method for simultaneous estimation of Olmesartan Medoxomil and Metoprolol Succinate in pharmaceutical dosage form

Aim and Backrgound: A simple, rapid, precise and isocratic RP-HPLC (Reverse Phase High Performance Liquid Chromatography) method is aimed to develop for the simultaneous estimation of Olmesartan Medoxomil and Metoprolol Succinate in bulk drug and pharmaceutical dosage form. Materials and Methods: The quantification is carried out using YMC-Pack CN (250 × 4.6mm, 5.0μm) column and the mobile phase comprises of 0.05% Trifluoro acetic acid (TFA) and Acetonitrile (ACN) (70:30v/v). The flow rate is 1.0ml/min. The eluent is monitored at 220nm. The retention times of Olmesartan Medoxomil and Metoprolol Succinate are 7.9min and 4.1min respectively. The method is validated in terms of linearity, precision, accuracy, specificity, limit of detection and limit of quantitation. Results: Linearity and percentage recoveries of both Olmesartan Medoxomil and Metoprolol Succinate are in the range of 5–35μg/ml and 100 ± 2%, respectively. The stress testing of both the drugs individually and their mixture is carried out under acidic, alkaline, oxidation, photo-stability and thermal degradation (dry heat and wet heat) conditions and its degradation products are well resolved from the analyte peaks. Conclusion: This method was successfully validated for accuracy, precision, and linearity.

Rapid determination of human globin chains using reversed-phase high-performance liquid chromatography

Reversed-phase high-performance liquid chromatography (RP-HPLC) of human globin chains is an important tool for detecting thalassemias and hemoglobin variants. The challenges of this method that limit its clinical application are a long analytical time and complex sample preparation. The aim of this study was to establish a simple, rapid and high-resolution RP-HPLC method for the separation of globin chains in human blood. Red blood cells from newborns and adults were diluted in deionized water and injected directly onto a micro-jupiter C18 reversed-phase column (250mm×4.6mm) with UV detection at 280nm. Under the conditions of varying pH or the HPLC gradient, the globin chains (pre-β, β, δ, α, Gγ and Aγ) were denatured and separated from the heme groups in 12min with a retention time coefficient of variation (CV) ranging from 0.11 to 1.29% and a peak area CV between 0.32% and 4.86%. Significant differences (P<0.05) among three groups (normal, Hb H and β thalassemia) were found in the area ratio of α/pre-β+β applying the rapid elution procedure, while P≥0.05 was obtained between the normal and α thalassemia silent/trait group. Based on the ANOVA results, receiver operating characteristic (ROC) curve analysis of the δ/β and α/pre-β+β area ratios showed a sensitivity of 100.0%, and a specificity of 100.0% for indicating β thalassemia carriers, and a sensitivity of 96.6% and a specificity of 89.6% for the prediction of hemoglobin H (Hb H) disease. The proposed cut-off was 0.026 of δ/β for β thalassemia carriers and 0.626 of α/pre-β+β for Hb H disease. In addition, abnormal hemoglobin hemoglobin E (Hb E) and Hb Westmead (Hb WS) were successfully identified using this RP-HPLC method. Our experience in developing this RP-HPLC method for the rapid separation of human globin chains could be of use for similar work.

Rapid determination of main constituents of packed juices by reverse phase-high performance liquid chromatography: an insight in to commercial fruit drinks

The present work reports the compositional analysis of thirteen different packed fruit juices using high performance liquid chromatography (HPLC). Vitamin C, organic acids (citric and malic) and sugars (fructose, glucose and sucrose) were separated, analyzed and quantified using different reverse phase methods. A new rapid reverse phase HPLC method was developed for routine analysis of vitamin C in fruit juices. The precision results of the methods showed that the relative standard deviations of the repeatability and reproducibility were <0.05 and <0.1 respectively. Correlation coefficient of the calibration models developed was found to be higher than 0.99 in each case. It has been found that the content of Vitamin C was less variable amongst different varieties involved in the study. It is also observed that in comparison to fresh juices, the packed juices contain lesser amounts of vitamin C. Citric acid was found as the major organic acids present in packed juices while maximum portion of sugars was of sucrose. Comparison of the amount of vitamin C, organic acids and sugars in same fruit juice of different commercial brands is also reported.

Development and validation of a rapid reversed-phase HPLC method for the determination of the non-nucleoside reverse transcriptase inhibitor dapivirine from polymeric nanoparticles

The objective of this work was to develop and validate a rapid reversed-phase (RP) high-performance liquid chromatography (HPLC) method for the in vitro pharmaceutical characterization of dapivirine-loaded polymeric nanoparticles. Chromatographic runs were performed on a RP C18 column with a mobile phase comprising acetonitrile–0.5% (w/v) triethanolamine solution in isocratic mode (80:20, v/v) at a flow rate of 1 ml/min. Dapivirine was detected at a wavelength of 290 nm. The method was shown to be specific, linear in the range of 1–50 μg/ml ( R 2 = 0.9998), precise at the intra-day and inter-day levels as reflected by the relative standard deviation values (less than 0.85%), accurate (recovery rate of 100.17 ± 0.35%), and robust to changes in the mobile phase and column brand. The detection and quantitation limits were 0.08 and 0.24 μg/ml, respectively. The method was successfully used to determine the loading capacity and association efficiency of dapivirine in poly(lactic- co-glycolic acid)-based nanoparticles and its in vitro release.

Ultra-fast separation of wheat glutenin subunits by reversed-phase HPLC using a superficially porous silica-based column

A relatively new, unique column packing material for reversed-phase high-performance liquid chromatography (RP-HPLC) was evaluated for rapid separation of wheat glutenin protein subunits. The product named “Poroshell” by the manufacturer consists of a solid core and a porous coat instead of solid silica spheres used in conventional RP-HPLC column packing. This architecture favours rapid mass transfer, facilitating faster reversed-phase separations of biomolecules compared to conventional silica columns. The main objective of this study was to evaluate the quality of separations of glutenin subunits (GS), as well as to optimize conditions to produce the fastest possible run times without sacrificing resolution using a Poroshell 300SB-C 8 2.1×75 mm column. The stability of GS separations over time was also assessed. Two different bread wheat genotypes were used for optimization of separation conditions and six more common and durum wheat genotypes possessing different subunit combinations were used for further evaluation. Glutenin protein was extracted with 0.08 M Tris–HCl buffer (pH 7.5) containing 50% 1-propanol under reducing conditions after pre-extraction of soluble proteins with 50% 1-propanol. Optimization of GS resolution and sample throughput by RP-HPLC was assessed in response to variation in eluent flow rate, acetonitrile (ACN) gradient, and column temperature. The best resolution of both HMW- and LMW-GS was obtained in 13 min using a 23–44% ACN gradient with a flow rate of 0.7 mL/min at 65 °C. Subunit elution times and integrated areas were highly repeatable even after several hundred injections. Highly satisfactory separation of HMW-GS and quantification of ratio of HMW- to LMW-GS were achieved in less than 4 min per sample using a modified HPLC gradient. Ratio of HMW- to LMW-GS was unaffected by the speed of the separations. As well, the elution order of HMW- and LMW-GS was unaffected by the rapid analysis, compared to conventional RP-HPLC separations, so no new learning was required for interpreting chromatograms and classification of subunits. The rapid RP-HPLC method using the Poroshell column appears to be very well suited for routine quantification of HMW-GS and LMW-GS especially for purposes of wheat quality screening and wheat cultivar development activities where large numbers of samples are typically encountered.

High-throughput analytical strategy with combined planar and column liquid chromatography for improvement of the poppy (Papaver somniferum L.) with a high alkaloid content

Poppy capsules with a high alkaloid content are of great importance to the pharmaceutical industry, because approximately 35 000 tons of straw (capsule with short stem), 350 tons of straw concentrate, and 1000 tons of opium are used annually for extraction of morphinane alkaloids. The combined use of four different liquid chromatographic methods is proposed for determination of alkaloid content. In the first, semi-quantitative, method screening is performed by multilayer overpressured-layer chromatography (MLOPLC) in which 142 samples are separated on silica as stationary phase within 5 s per sample. If the morphine content is >1.3% it is then measured quantitatively by NPHPTLC (normal-phase high-performance thin-layer chromatography) combined with densitometric evaluation. A second, quantitative, determination is always performed by means of a rapid RPHPLC (reversed-phase high-performance liquid chromatography) method in which the separation time is less than 4 min per sample. If the difference between the alkaloid content measured by use of the last two methods is >12% a confirmatory RPHPLC method with increased selectivity and analysis time (15 min) must be used. The high throughput strategy presented has been used for analysis of ca. 15 000 samples per year, per genotype. Systematic selection, cross-breeding, and this analytical strategy with combined planar and column liquid chromatographic methods resulted in the discovery of two new candidate cultivars with high morphine (ca. 2%) and thebaine (ca. 1.5%) content.