Liquid Chromatography-diode Array Detection Method Research Articles

A novel HPLC method for the determination of zonisamide in human plasma using microextraction by packed sorbent optimised by experimental design

A novel high-performance liquid chromatography-diode array detection method based on microextraction by packed sorbent as a sample preparation approach was developed and validated for the determination of zonisamide in human plasma.

Development and optimization of an HPLC–DAD method for quantification of six petroleum hydrocarbon compounds in aqueous samples

ABSTRACTBenzene, toluene, and xylene isomers (BTXs) and pyrene, benzo(b)fluoranthene, and benzo(a)pyrene (polycyclic aromatic hydrocarbons) are common pollutants found in many industrial effluents and in aquifers due to fossil fuels spill from underground storage reservoirs. For these reasons, the determination of these compounds has gained importance in the last decades. In this work, a simultaneous, fast, and accurate quantification of six petroleum hydrocarbon compounds (such as BTXs, pyrene, benzo(b)fluoranthene, and benzo(a)pyrene) using a high-performance liquid chromatography–diode array detector method has been demonstrated. The proposed method is suitable for the direct aqueous sample evaluation and also brings advantages, including the use of small volumes of organic solvents, with high resolution, reducing the analysis cost. The method was also checked using synthetic and real samples, including those containing surfactants, commercial gasoline, and river water samples spiked with petroleum hydrocarbon compounds.

Determination of lamotrigine in human plasma and saliva using microextraction by packed sorbent and high performance liquid chromatography–diode array detection: An innovative bioanalytical tool for therapeutic drug monitoring

A ground-breaking high-performance liquid chromatography-diode array detection method based on microextraction by packed sorbent (MEPS) as sample preparation approach is described herein for determination of lamotrigine (LTG), a narrow therapeutic index drug, in human plasma and saliva. MEPS variables and chromatographic conditions were optimized to achieve appropriate selectivity and sensitivity using small sample volumes (100μL). The chromatographic separation of LTG and chloramphenicol [internal standard (IS)] was accomplished in <5min on a C18-column, at 35°C, using a mobile phase composed by acetonitrile/methanol/water-triethylamine 0.3% at pH6.0 (13:13:74, v/v/v) pumped isocratically at 1mL/min. LTG and IS were detected at 215nm. A good linearity was obtained for LTG (r2≥0.9936) in the range of 0.1–20μg/mL in plasma and saliva, with the limit of quantification of 0.1μg/mL. The method was shown to be precise (RSD ≤14.5%) and accurate (bias±13.4%), and the absolute recovery ranged from 64.9% to 73.6%. The stability of LTG was demonstrated in plasma and saliva samples in all studied conditions. The proposed assay was applied to the analysis of real human plasma and saliva samples from epilepsy patients under LTG therapy and the results support its usefulness for therapeutic drug monitoring.

Simultaneous separation of antihyperlipidemic drugs by green ultrahigh-performance liquid chromatography–diode array detector method: Improving the health of liquid chromatography

Statins in combination with fibrates show beneficial effects on the lipoprotein profile of patients because they have positive complimentary effects on lipid profile. A new green ultrahigh-performance liquid chromatography–diode array detector method for simultaneous analysis of simvastatin (SMV) and fenofibrate (FNF) in standard form, marketed formulations, and self-emulsifying drug delivery system formulations was developed and validated in the present investigation. The method utilized C18 as stationary phase and a combination of methanol:water (8:2) as an eluent. It was found that selected eluent provided short run time (2.5 minutes), better peak symmetry and satisfactory values of other chromatographic parameters such as resolution (Rs=2.325), capacity factor (k, 3.0 and 4.2 for SMV and FNF, respectively), selectivity (α =1.4), and number of theoretical plates (N, 4265 and 5285 for SMV and FNF, respectively). An excellent linear relationship (r2 0.998 and 0.997 for SMV and FNF, respectively) was observed for linear regression data for the calibration plots. The developed system was validated for accuracy, precision, robustness (˃ 2% for both drugs) and recovery (98–102% for both drugs). Results obtained from the statistical treatment of the values obtained for different parameters proved that the method is suitable, reproducible, and selective for the simultaneous analysis of SMV and FNF in bulk, marketed, and self-emulsifying drug delivery system formulations. The replacement of commonly applied toxic solvents with innocuous and environmentally benign solvents provides a better option than the more toxic processes in drug analysis.

Stability-indicating HPLC-DAD method development, validation, and stress degradation studies for triamterene and xipamide in their combined tablet dosage form

A simple stability-indicating high-performance liquid chromatography-diode array detection (HPLC-DAD) method has been developed for the simultaneous determination of triamterene (TRI) and xipamide (XIP) in presence of the degradation products generated in studies of forced decomposition. Drugs were subjected to stress by hydrolysis (acidic, alkaline, and neutral), oxidation, photolysis (254 and 365 nm), and dry and wet heat treatments. Degradation occurs under acidic and alkaline conditions (TRI only), oxidative stress (TRI and XIP), and by photolysis (XIP only), but both drugs were stable under other stress conditions investigated. Separation of the two drugs from all the degradant peaks was achieved within 11 min using C8 column (250 × 4.6 mm, 5 μm) and mobile phase consisting of acetonitrile and 0.05 M phosphate buffer adjusted to pH 4 delivered at a flow rate of 1 mL min−1 using gradient elution system. The drugs were quantified at 220 nm using photodiode array detector, based on peak area. Peak homog...

Preparation of a nitro-substituted tris(indolyl)methane modified silica in deep eutectic solvents for solid-phase extraction of organic acids

A new sorbent for solid-phase extraction was synthesized by chemical immobilization of nitro-substituted tris(indolyl)methane on silica in new and green deep eutectic solvents. Elemental analysis results indicated that deep eutectic solvents could be an alternative to the traditional solvents in preparing nitro-substituted tris(indolyl)methane modified silica. Coupled with high performance liquid chromatography, the extraction performance of the sorbent was evaluated by using four organic acids as model analytes. The rebinding experiments results showed that the nitro-substituted tris(indolyl)methane modified silica sorbent had a good adsorption capacity towards the selected organic acids. Under the appropriate experimental conditions, good precision and wide linear ranges with coefficient of determination (R2) of higher than 0.9957 were obtained, and the limits of detection were in the range of 0.50–2.0μgL−1 for the organic acids tested. The developed solid-phase extraction–high performance liquid chromatography-diode array detection (SPE–HPLC-DAD) method was successfully applied for the determination of organic acids in two drinking samples with recoveries ranging from 76.7% to 110.0% and 67.7% to 104.0% for all the selected organic acids, respectively.

Assessment of diversity amongst natural populations of Gymnema sylvestre from India and development of a validated HPLC protocol for identification and quantification of gymnemagenin

In order to supply uniform, genuine, good quality raw material to the pharmaceutical industries and to reduce the burden on natural stocks, cultivation of medicinal crops is the need of the hour. However, improved varieties with optimum levels of active ingredients have so far not been developed in a number of important medicinal crops. Considering this, an investigation was undertaken to assess the extent of variability amongst the natural populations of Gurmar (Gymnema sylvestre), an important anti-diabetic plant of the Indian Systems of Medicine. Evaluation of the accessions for morphological parameters revealed highly significant differences for leaf related parameters viz. length, width, fresh as well as dry weight and petiole length, which directly contribute to the biological yield of the plant. Further, a validated high performance liquid chromatography-diode array detection (HPLC-DAD) method was also developed for identification and quantification of bioactive principle i.e., gymnemagenin in a gradient elution mode using solvent mixture composing of acetonitrile (solvent A), potassium dihydrogen orthophosphate (10mM, solvent B) both solvent A and B containing orthophosphoric acid (0.05%, v/v). Results revealed significant differences for gymnemagenin content amongst the accessions evaluated. These accessions could be used in breeding programs for development of cultivars with optimum levels of gymnemagenin, which in turn may promote the cultivation of this high value medicinal crop.

Determining Seasonal Changes in Three Major Phenolic Compounds from Bark of Saraca asoca in Comparison with Local Market Sample Using RP-HPLC Analysis

The aim of the present study was to investigate seasonal variation of the polyphenolic compounds viz., gallic acid, catechin, and epicatechin in the bark of Saraca asoca by using reverse phase high performance liquid chromatography–diode array detector method. It was observed that epicatechin was present in abundance as compared to gallic acid throughout the seasons. In market samples epicatechin was not detected even in trace amount, but gallic acid was present in high amount as compared to freshly collected bark in different seasons.

Development and validation of an high-performance liquid chromatography-diode array detector method for the simultaneous determination of six phenolic compounds in abnormal savda munziq decoction.

Aims:Given the high-effectiveness and low-toxicity of abnormal savda munziq (ASMQ), its herbal formulation has long been used in traditional Uyghur medicine to treat complex diseases, such as cancer, diabetes, and cardiovascular diseases.Settings and Design:ASMQ decoction by reversed-phase high-performance liquid chromatography coupled with a diode array detector was successfully developed for the simultaneous quality assessment of gallic acid, protocatechuic acid, caffeic acid, rutin, rosmarinic acid, and luteolin. The six phenolic compounds were separated on an Agilent TC-C18 reversed-phase analytical column (4.6 × 250 mm, 5 μm) by gradient elution using 0.3% aqueous formic acid (v/v) and 0.3% methanol formic acid (v/v) at 1.0 mL/min.Materials and Methods:The plant material was separately ground and mixed at the following ratios (10): Cordia dichotoma (10.6), Anchusa italic (10.6), Euphorbia humifusa (4.9), Adiantum capillus-veneris (4.9), Ziziphus jujube (4.9), Glycyrrhiza uralensis (7.1), Foeniculum vulgare (4.9), Lavandula angustifolia (4.9), Dracocephalum moldavica L. (4.9), and Alhagi pseudoalhagi (42.3).Statistical Analysis Used:The precisions of all six compounds were <0.60%, and the average recoveries ranged from 99.39% to 104.85%. Highly significant linear correlations were found between component concentrations and specific chromatographic peak areas (R2 > 0.999).Results:The proposed method was successfully applied to determine the levels of six active components in ASMQ.Conclusions:Given the simplicity, precision, specificity, and sensitivity of the method, it can be utilized as a quality control approach to simultaneously determining the six phenolic compounds in AMSQ.

Analysis of the influence of processing of stir-baking with glycyrrhizae on the main components of Euodiae Fructus by high-performance liquid chromatography with diode array detector

Euodiae Fructus is one of the most commonly used Chinese herbs in China. Specifically, the crude Euodiae Fructus and its processed products of Gancao Zhi Pin are used clinically for the treatment of different diseases. In order to improve the quality control standard and evaluate the crude and processed Euodiae Fructus, in this study, a simple and sensitive high-performance liquid chromatography-diode array detector method was developed for the simultaneous determination of five major compounds in Euodiae Fructus. The results indicated that the five components had significant linear relation (r2 ≥ 0.9997) between the peak area and the injected concentration. The average recoveries of the five components were in the range from 97.38% to 102.56%. Overall intra- and inter-day variations were less than 1.36%. The developed method can be applied to the intrinsic quality control of crude and processed Euodiae Fructus.

Herb-drug pharmacokinetic interaction between carica papaya extract and amiodarone in rats.

Carica papaya has been traditionally used worldwide in folk medicine to treat a wide range of ailments in humans, including the management of obesity and digestive disorders. However, scientific information about its potential to interact with conventional drugs is lacking. Thus, this work aimed to investigate the interference of a standardized C. papaya extract (GMP certificate) on the systemic exposure to amiodarone (a narrow therapeutic index drug) in rats. In the first pharmacokinetic study, rats were simultaneously co-administered with a single-dose of C. papaya (1230 mg/kg, p.o.) and amiodarone (50 mg/kg, p.o.); in the second study, rats were pre-treated for 14 days with C. papaya (1230 mg/kg/day, p.o.) and received amiodarone (50 mg/kg, p.o.) on the 15th day. Rats of the control groups received the herbal extract vehicle. Blood samples were collected before dosing and at 0.25, 0.5, 1, 2, 4, 6, 8 and 12 h following amiodarone administration; in addition, at 24 h post-dose, blood and tissues (heart, liver, kidneys and lungs) were also harvested. Thereafter, the concentrations of amiodarone and its major metabolite (mono-N-desethylamiodarone) were determined in plasma and tissue samples employing a high-performance liquid chromatography-diode array detection method previously developed and validated. In both studies was observed a delay in attaining the maximum plasma concentrations of amiodarone (tmax) in the rats treated with the extract. Nevertheless, it must be highlighted the marked increase (60-70%) of the extent of amiodarone systemic exposure (as assessed by AUC0-t and AUC0-∞) in the rats pre-treated with C. papaya comparatively with the control (vehicle) group. The results herein found suggest an herb-drug interaction between C. papaya extract and amiodarone, which clearly increase the drug bioavailability. To reliably assess the clinical impact of these findings appropriate human studies should be conducted.

Multiple compounds determination and fingerprint analysis ofAgrimonia pilosaLedeb by high-performance liquid chromatography

Summary In the present paper, a simple and reliable high-performance liquid chromatography-diode array detection (HPLC-DAD) method was developed both for quantitative determination and fingerprint analysis of Agrimonia pilosa Ledeb for quality control. Under the optimized HPLC conditions, seven bioactive compounds including rutin, quercetin-3-rhamnoside, luteoloside, tiliroside, apigenin, kaempferol, and agrimonolide were determined simultaneously. For fingerprint analysis, 11 common peaks were selected as the characteristic peaks to evaluate the similarities of 16 different samples collected from different origins in China. Besides, hierarchical cluster analysis (HCA) was also performed to evaluate the variation of the raw materials. This is the first report of using a simple method for quality control of A. pilosa Ledeb through multi-component determination and chromatographic fingerprint analysis to the best of our knowledge.

Quantitative and structural analysis of amides and lignans in Zanthoxylum armatum by UPLC-DAD-ESI-QTOF–MS/MS

A rapid and simple ultra performance liquid chromatography-diode array detection (UPLC-DAD) method has been developed for the simultaneous quantification of four biologically important furofuran lignans, asarinin, sesamin, fargesin and kobusin, and an amide, armatamide in Zanthoxylum armatum within 7min. The separation was carried out on a BEH C18 column (2.1mm×100mm, 1.7μm particle size) with 0.05% formic acid aqueous solution and acetonitrile as mobile phase under gradient conditions at 25°C. The method was validated and found to be linear (R2≥0.9997), precise in terms of peak areas (intra-day RSDs≤0.62% and inter-day RSDs≤2.95%) and accurate (95.6–104.0%). The developed method was applied to the quality assessment of different parts (leaves, bark and seeds) of Z. armatum including locational variation of leaves samples. Significant variation in the amount of amides and furofuran lignans was observed. Tandem electrospray ionization–mass spectrometry (UPLC-DAD-ESI–MS/MS) of samples led to the identification of sixteen compounds in the category of amides and furofuran lignans.

Extraction of Three Bioactive Diterpenoids from Andrographis paniculata: Effect of the Extraction Techniques on Extract Composition and Quantification of Three Andrographolides Using High-Performance Liquid Chromatography

Andrographis paniculata (Burm.f.) wall.ex Nees (Acanthaceae) or Kalmegh is an important medicinal plant finding uses in many Ayurvedic formulations. Diterpenoid compounds andrographolides (APs) are the main bioactive phytochemicals present in leaves and herbage of A. paniculata. The efficiency of supercritical fluid extraction (SFE) using carbon dioxide was compared with the solid-liquid extraction techniques such as solvent extraction, ultrasound-assisted solvent extraction and microwave-assisted solvent extraction with methanol, water and methanol-water as solvents. Also a rapid and validated reverse-phase high-performance liquid chromatography-diode array detection method was developed for the simultaneous determination of the three biologically active compounds, AP, neoandrographolide and andrograpanin, in the extracts of A. paniculata. Under the best SFE conditions tested for diterpenoids, which involved extraction at 60°C and 100 bar, the extractive efficiencies were 132 and 22 µg/g for AP and neoandrographolide, respectively. The modifier percentage significantly affected the extraction efficiency.

Residues, half-life times, dissipation, and safety evaluation of the acaricide fenpyroximate applied on grapes

A validated high-performance liquid chromatography–diode array detector method for simultaneous determination of the acaricide fenpyroximate on grape was developed. Estimated limit of detection and limit of quantification for fenpyroximate were 0.01 and 0.05 mg kg−1, respectively. The intra- and inter-day precisions performed with relative standard deviation were better than 9.3% and 8%, respectively, while recoveries were in the range of 88.5%–100.4%. Residue levels of fenpyroximate in grape samples collected 10 days after field application were below the established maximum residue level values. The dissipation rates of fenpyroximate were described using first-order kinetics and its half-life, were approximately 3.5 days in grape. This study provides basic information for developing regulations to safeguard the use of fenpyroximate in grapes and prevent any potential health concerns for consumers.

Development of gradient HPLC-DAD method for assay of ternary mixture containing amebicide and analgesic drugs

Summary Validated gradient high-performance liquid chromatography-diode array detection (HPLC-DAD) method has been developed for simultaneous determination of diloxanide furoate (DIL), mebeverine hydrochloride (MBV), and metronidazole (MET) in their pharmaceutical preparation. This method was based on a reversed-phase HPLC separation of the cited drugs on a C-18 column (150 mm × 4.6 mm, 5 μm) with a gradient elution system of 0.05 M phosphate buffer with 1% (v/v) of triethylamine adjusted to pH 3.0-methanol as the mobile phase at the flow rate of 1.0 mL min−1. The separation was carried out at ambient temperature. Quantitation was achieved with DAD detection at 260 nm for DIL and MEB, and at 320 for MET based on peak area with linear calibration curves at concentration ranges 4–30, 1–20, and 1–30 μg mL−1 for DIL, MEB, and MET, respectively. The proposed chromatographic method was successfully applied to the determination of the investigated drugs in pharmaceutical preparation. It was validated in complian...

Simultaneous Determination of Structurally Diverse Compounds in Different Fangchi Species by UHPLC-DAD and UHPLC-ESI-MS/MS

Two bisbenzylisoquinoline alkaloids, two morphine alkaloids, one aporphine alkaloid, syringaresinol and aristolochic acid І were selected as marker compounds and simultaneously analyzed using an ultra-high pressure liquid chromatography-diode array detection (UHPLC-DAD) method. These marker compounds were used for the quality control of Fangchi species of different origins, including Sinomenium acutum, Stephaniatetrandra, Cocculus trilobus and Aristolochia fangchi. A reversed-phase UHPLC-DAD method was developed and validated for the simultaneous quantification of structurally diverse markers in different Fangchi species. In addition, an UHPLC-electrospray ionization tandem mass spectrometry (ESI-MS/MS) method was used for marker identification in Fangchi species, which provided diagnostic MS/MS spectral patterns that were dependent upon the marker structures. The UHPLC-MS/MS data were used to confirm and complement the UHPLC-DAD quality evaluation results. Additionally, magnoflorine and syringaresinol were observed for the first time in S. tetrandra and C. trilobus, respectively. Twenty different Fangchi species samples were analyzed for aristolochic acid I, syringaresinol and the alkaloids using the UHPLC-DAD and MS/MS method. Based on the levels of markers and principal component analysis (PCA), this method allowed for the clear classification of the samples into four different groups representing samples originating from the four species.

Quantitative Assessment of Traditional Oriental Herbal Formulation Samhwangsasim-tang Using UPLC Technique

A specific and reliable ultra-performance liquid chromatography-diode array detection method has been developed and validated for the quantitative assessment of a traditional Oriental herbal formulation, Samhwangsasim-tang (SST). A Halo reversed-phase amide column (2.7 µm, 4.6 × 150 mm) was used to separate marker compounds; detection was conducted by ultraviolet absorbance at 250 nm. The column temperature was maintained at 45°C. A mobile phase consisting of acetonitrile (A) and 0.1% trifluoroacetic acid in water (B) was found to be suitable for the separation, at a flow rate of 1.8 mL/min with gradient elution. Linearity, specificity, precision and recovery were calculated to validate the method and instrumentation. Under the described conditions, all marker compounds (rhaponticin, berberine, palmatine, baicalin, baicalein and wogonin) were collected within 25 min. All calibration curves of components showed good linearity (correlation coefficient > 0.9996). The limit of detection and limit of quantification ranged from 0.08-3.05 and 0.23-8.12 µg/mL, respectively. The relative standard deviation (RSD) and repeatability values of intra-day and inter-day precision were less than 2.30, 2.99 and 1.82%, respectively. In the recovery test, the accuracy ranged from 97.56-103.30% with RSD values less than 2.63%. The developed method was simple, specific, sensitive, accurate, precise and reproducible for the quantification of the active chemical constituents of SST. The simultaneous analysis of the contents of marker compounds in different SST samples prepared by different extraction procedures and different commercial products was successfully evaluated.

High Performance Liquid Chromatography-Diode Array Detector Method for the Determination of Tartrazine and Indigotine

High Performance Liquid Chromatography-Diode Array Detector Method for the Determination of Tartrazine and Indigotine

Simultaneous Determination of 4-Substituted Cathinones (4-MMC, 4-MEC and 4-FMC) in Human Urine by HPLC-DAD

This study developed a selective and rapid high-performance liquid chromatography-diode array detection method for the confirmation of different cathinone derivates in human urine. Samples were prepared by solid-phase extraction (SPE) using procaine hydrochloride as the internal standard. The chromatographic separation was performed on a Kinetex PFP column using isocratic elution. The mobile phase was composed of a mixture of acetonitrile (33%, v/v) and 0.005M ammonium trifluoroacetate buffer (67%, v/v; pH 4.93 ± 0.03) with a flow rate of 0.350 mL/min. The diode array detection was performed at 262 nm. The method was linear over the concentration range of 25-2,400 ng/mL. Intra-day and inter-day precision values for cathinones were less than 1.26% (relative standard deviation). The limit of detection for any compounds extracted from human urine by the optimized SPE method was 40 ng/mL and the limit of quantification was 100 ng/mL in the urine. The recovery rate of SPE was between 71 and 82% with a lower relative standard deviation than 2.35%.