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Acta Chromatographica
Authors:
Waqar Siddique
,
Rai Muhammad Sarfraz
,
Muhammad Zaman
,
Riffat Khan
,
Maria Gul
,
Farhan Asghar
,
Tangina Malik
,
Asiya Saif
,
Qurat-Ul-Ain Shamim
,
Ahmad Salawi
,
Meshal Alshamrani
,
Yosif Almoshari
, and
Fahad Y. Sabei

Abstract

One of the most effective, rapid, and simple methods reversed-phase high-performance liquid chromatography (RP-HPLC) was used for simultaneous development and validation of Eletriptan hydrobromide (ELE HBR) and Itopride hydrochloride (ITP HCL) in combination. The method was validated based on the regulations of United States Pharmacopeia (USP) and International Conference on Harmonization (ICH) guidelines. Separation of both drugs was achieved within approximately 5 min by using a mobile phase made up of a 70:30 ratio of phosphate buffer and acetonitrile having a flow rate of 1 mL min−1. Furthermore, a comprehensive study was conducted on precision, accuracy, linearity, inter-day, intra-day studies, an assay of formulated films, and stability studies of combined prepared film. Co-efficient of correlation ranged between 0.9993, and 0.9965 for ELE HBR and ITP HCL respectively. The accuracy of the developed method was accurate as drug recoveries in both cases of ITP HCL, and ELE HBR falls between (99.87, 99.96, and 99.84%) to (99.81, 99.12, and 98.44%) respectively having a concentration range of solutions between 10, 30 and 50 μg mL−1 dilution. Films developed by using both drugs in combination were then validated for assay studies, and it was found that substantial results of 99.05%, and 99.87% were found in the case of ITP HCL and ELE HBR respectively. The stability of the solution and mobile phase showed the method's accuracy as the results were 97% for ITP HCL and 99% for ELE HBR. The proposed method developed for simultaneous determination of ITP HCL and ELE HBR was developed and validation and no interaction of any excipient were found.

Open access

Abstract

In this work, a simple and rapid high performance liquid chromatography tandem mass spectrometry (HPLC-MS/MS) method was developed and validated to carry out the simultaneous measurement of busulfan (BU) and phenytoin (PHT) in the plasma of children. In this method, plasma sample could be prepared by one-step protein precipitation using 1 mL of methanol/water (1:1, v/v). After centrifugation (14,500 rpm, 5 min, 4 °C), 10 μL of the supernatant was injected into a Hypersil Gold C18 column (150 × 2.1 mm, 5 μm, Thermo Fisher Scientific) for separation by gradient elution. Quantification was carried out using multiple reactions monitoring (MRM) under positive scan mode. In the method verification, the calibration curves of BU and PHT showed satisfactory linearity (r > 0.99) at the concentration ranging from 0.02 to 20 μg mL−1. The accuracy and precision were tested at four concentration levels (including the LLOQ level) with the relative error (RE) ranging from −0.80% to 11.45% and coefficient of variation (CV) between 0.93% and 7.74%. There was no pronounced matrix effect to interfere with the quantitative analysis. Compared to determine BU and PHT using two individual methods, less pre-treatment process, labor and blood sample volume are required in this proposed method. Finally, this method was successfully applied to the therapeutic drug monitoring of BU and PHT for children underwent hematological stem cell transplantation.

Open access
Acta Chromatographica
Authors:
Tiantian Lu
,
Xiaohong Wang
,
Qi Zhang
,
Kun Liu
,
Tongxin Xu
,
Quande Wang
,
Pengfei Zhao
, and
Zhongzhe Cheng

Abstract

Solasodine, a steroidal alkaloid, is distributed extensively in Solanaceae plants with multiple biological activities such as neuroprotection, antineoplastic and anticonvulsant activities. However, there is little information about the excretion of intact solasodine in vivo. To investigate its excretion, a reliable LC-MS/MS method for quantitation solasodine in rat urine and feces was established and validated. Sample preparation was carried out by liquid-liquid extraction using MTBE as extractant. Moreover, rat urine was preconditioned with BSA, an anti-adsorptive additive, to prevent the nonspecific binding of solasodine to containers and tubes. The method was validated over the range of 4–2000 ng mL−1. The correlation coefficient (r 2) were all above 0.999. The intra- and inter-day precision and accuracy were within 16.9% and between −11.0 and 8.9%, respectively. The recovery of solasodine in urine and feces was in the range of 72.5–80.3 and 75.7–80.2%, respectively. IS-normalized matrix factor ranged from 0.94 to 1.12 with RSD% ≤4.02%. This method was successfully applied to the excretion study of solasodine following oral and intravenous administration.

Open access

Abstract

A new pretreatment method termed ultrasound-assisted extraction (UAE) which is combined with solid-phase extraction which is combined with dispersive liquid-liquid microextraction (SPE-DLLME) followed by gas chromatography-flame ionization detector (GC-FID) analysis has been developed for the determination of diazinon in garden parsley as vegetable samples. The analyte was extracted from garden parsley sample using ultrasound-assisted extraction followed by solid-phase extraction followed by dispersive liquid-liquid microextraction. Various parameters that affect the efficiency of the extraction techniques have been optimized. The calibration plot was linear in the range of 5.0–1,000 μg kg−1 with detection limit of 1.0 μg kg−1 for diazinon in garden parsley samples. The results confirm the suitability of the UAE-SPE-DLLME-GC-FID as a sensitive method for the analysis of the targeted analyte in garden parsley samples.

Open access

Abstract

Fuke Yangrong pill, a traditional Chinese patent medicine, with the functions of nourishing qi and blood, soothing liver and relieving depression, regulating menstruation and removing blood stasis, is composed of 16 Chinese medicinal herbs. For quality control purpose, an HPLC method was established for simultaneous quantification of paeoniflorin, hesperidin and ligustilide in Fuke Yangrong pill. With acetonitrile-0.1% formic acid as mobile phase, gradient elution was carried out using Agilent ZORBAX Eclipse Plus C18 column (250 mm × 4.6 mm, 5.0 μm) at 1.0 mL min−1. Detection wavelength was set at 230 nm for paeoniflorin, 280 nm for hesperidin and ligustilide. The temperature was 30 °C. There was a good linearity between the peak area and the concentration of each component to be measured within their linear range (r ≥ 0.9994). The average recoveries were between 98.6% and 102.6% with RSDs no more than 2.93%. This method was validated to be accurate and convenient, which is suitable for the quality control of Fuke Yangrong pill.

Open access

Abstract

In this study, an accurate, simple, economical and precise Reversed-Phase High Pressure Liquid Chromatography (RP-HPLC) method was developed for the simultaneous estimation of Ozenoxacin and Benzoic Acid in a pharmaceutical cream formulation, according to the International Conference on Harmonisation (ICH) guidelines. Chromatographic separation was achieved by gradient elution, on RP-HPLC Instrument, equipped with column C8 (150 mm × 4.6 mm, 5 μm particle size) using Ultra Violet (UV) detector at 235 nm wavelength, by using Mobile Phase A: triethylamine, trifloroacetic acid and water (1:1:1000) and Mobile Phase B: methanol and Diluent: water, acetonitrile and triethylamine (500:500:1), at flow rate 0.8 mL min−1; injection volume of 20 μL; column oven temperature 45 °C and sample temperature: 25 °C; Run time: 15 min. All the validation parameters were within the acceptance criteria, as per ICH requirements, for Ozenoxacin and Benzoic acid. Consequently, this method has found to be validated, simple, rapid and successfully applicable, to the simultaneous estimation of Ozenoxacin and Benzoic acid by RP-HPLC, for routine analytical testing in quality control, with a run time of 15 min and for future research studies. Forced degradation of Ozenoxacin cream 1% w/w formulation was performed and found that validated method has stability indicating potential that needs to be further studied.

Open access

Abstract

Ivosidenib (AG-120) is an unlisted, but estimated to be valid, oral inhibitor for isocitrate dehydrogenase 1 (IDH1) in the phase Ⅰ study of IDH1-mutated acute myeloid leukemia (AML) patients. This paper presents the investigation and validation of a rapid, effective, qualitative and quantitative determination method of ivosidenib in rat plasma by ultra-performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS). The samples were treated using acetonitrile precipitation to remove protein influence. Then, the supernatant was extracted to analyze plasma concentration traits. In the UPLC system, acetonitrile and water containing 0.1% formic acid were selected as a cosolvent mobile phase, applying a gradient elution to isolate compounds in a C18 column. Mass detections were performed on a triple quadruple mass spectrometer in positive ion mode. Electroshock characteristic fragment ionization was used for m/z 583.95→214.53 for ivosidenib for quantitative determination, m/z 583.95→186.6 for qualitative determination, and m/z 492.06→354.55 for IS. The selectivity, linearity, stability, accuracy and precision were verified by reaching the guideline criteria from European Medicine Agency (EMA) and the Food and Drug Administration (FDA). The calibration curve was linear over the concentration range of 2–2,000 ng mL−1 for ivosidenib in rat plasma with a lower limit of quantification (LLOQ) of at least 2 ng mL−1. Additionally, there was no distinct matrix effect or carry-over phenomenon. The method was successfully established and applied to separate ivosidenib from plasma, with the entire analytical process being performed within 3 min for each sample, which shows high-efficiency and convenience for further studies of ivosidenib.

Open access

Abstract

A fast reliable micellar electrokinetic methodology was investigated for the concurrent quantitation of six antimicrobial and anti-inflammatory drugs, namely, ciprofloxacin, dexamethasone, metronidazole, ornidazole, spiramycin and tinidazole. The method has the merits of rapidity, precision, and sensitivity. The separation was carried out in less than 7 min by applying a basic background electrolyte consisting of 25 mM disodium tetraborate buffer, pH 9 containing 50 mM SDS at 25 kV using photodiode array detector at 230 and 315 nm. The internal standard used during analysis was cromolyn sodium and validation was carried out following ICH guidelines. The proposed method showed linear response over the range from 0.5 to 10.0 μg mL−1 reaching limits of detection and limits of quantitation in the ranges of 0.09–0.2 μg mL−1 and 0. 27–0.6 respectively. The method's greenness was estimated using the GAPI tool where excellent greenness was concluded. Co-formulated or single-ingredient commercial preparations were investigated and the results were statistically evaluated.

Open access

Abstract

A simple, rapid, and sensitive method based on UPLC-MS/MS was developed to determine spiraeoside in mouse blood, and was applied to the pharmacokinetics and bioavailability of spiraeoside after mice after intravenous (a dose of 5 mg kg−1) and oral (a dose of 20 mg kg−1) administration. On HSS T3 column set at 40 °C, chromatographic separation was obtained with the mobile phase of acetonitrile and 0.1% formic acid using the gradient elution. Spiraeoside and internal standard (IS) were quantitatively analyzed using multiple reaction monitoring (MRM) mode in electrospray (ESI) positive interface. The MRM mode was monitoring the fragmentation of m/z 465.4→303.1 and m/z 451.3→ 289.2 for spironoside and IS, respectively. The results showed a good linear relationship was in the concentration range of 1–200 ng mL−1 (r > 0.998) and the lower limit of quantification (LLOQ) was 1.0 ng mL−1. The intra- and the inter-day precision (RSD%) of the method was within 14.0%, and the accuracy ranged from 90.0% to 115.0%. The extraction recovery of spriaeoside was better than 63.0%, and the matrix effects were in the range of 86%–98%. It also showed the half-life was short, and the absolute bioavailability was 4.0% in mice. Therefore, the established UPLC-MS/MS method was suitable for the pharmacokinetic and bioavailability study of spiraeoside in mice.

Open access