Ionic Samples: Reversed‐Phase, Ion‐Pair, and Ion‐Exchange HPLC

Snyder, Lloyd R.; Kirkland, J. J.; Glajch, Joseph L.

doi:10.1002/9781118592014.ch7

Cited by 3 publications

(1 citation statement)

References 60 publications

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“…Considering, that nearly all of the pH-related variation in retention of the drug happens for pH values within 1.5 units of the drug's pKa, efforts were made to choose a buffer that will maintain the mobile phase pH within 1.5 units of the drug's pKa, which is between pH 4.8 and 7.8. 22 It was observed that mobile phase of pH 5 gave the best resolution along with a number of theoretical plates (NTP), retention and tailing factor. Identification of wavelength maxima (λ max ) was carried out by scanning 20 µg/mL solution of RFX over the wavelength range of 200 to 400 nm on Shimadzu UV-1900 spectrophotometer; the software used was Lab Solutions.…”

Section: Methods Developmentmentioning

confidence: 99%

Stability-Indicating Liquid Chromatography Method for Rifaximin and LC-MS Characterization of its Potential Degradants

Chaturvedi,

Chopra,

Desai

et al. 2023

IJPQA

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Rifaximin (RFX) is a structural analog of rifampin that has been shown to be a gastrointestinal-selective antibiotic with broad-spectrum antibacterial properties, a pronounced safety profile, and limited drug interactions. Crohn’s disease, diarrhea, hepatic encephalopathy, irritable bowel syndrome, and traveler’s diarrhea caused by non-invasive diarrheagenic Escherichia coli, can all be treated with rifaximin. FDA has designated RFX as an orphan drug for the treatment of hepatic encephalopathy. There is a substantial need for analytical quality monitoring of Rifaximin to ensure the safety and efficacy of treatment. To generate degradants, forced degradation study of the drug was carried out in acid, alkali, oxidative, thermal, and photolytic stress conditions. The optimum separation of the drug, and its degradants was achieved on an Inertsil ODS-3V C18 column (250 X 4.6 mm X 5 μm) under gradient elution conditions using, 10 mM potassium dihydrogen orthophosphate (pH 5.0 ± 0.05) as mobile phase A, and acetonitrile as mobile phase B, at a flow rate of 1.0 mL/min. The run time was 41 minutes and the detection wavelength was 258 nm. The method was validated in accordance with the International Council for Harmonisation of Technical Requirements for Pharmaceuticals for Human use Guidelines. The drug was stable in neutral hydrolysis, photo and dry heat degradation conditions. The percentage degradation observed during acid, alkali hydrolysis and oxidative stress conditions were 70.46, 15.11 and 24.18, respectively. The degradants were investigated by LC-MS which indicated the presence of four (m/z 784.2, 744.5, 784.3, 753.8), three (m/z 744.5, 784.3, 753.8) and five (m/z 772.4, 838.4, 744.5, 753.8, and 801.9) degradants in acid, alkali and oxidative stress conditions, respectively. The structures of degradants were elucidated using Liquid chromatography–mass spectrometry (LC-MS) and Liquid chromatography tandem mass spectrometry (LC-MS/MS) analyses.

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Section: Methods Developmentmentioning

confidence: 99%

Stability-Indicating Liquid Chromatography Method for Rifaximin and LC-MS Characterization of its Potential Degradants

Chaturvedi,

Chopra,

Desai

et al. 2023

IJPQA

View full text Add to dashboard Cite

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Quantification of α-Acids in Fresh Hops by Reverse-Phase High-Performance Liquid Chromatography

et al. 2019

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This publication describes a method for the quantification by high-performance liquid chromatography (HPLC) of resinous compounds known as α-acids found in freshly harvested, unprocessed hops. This method provides consistent, efficient, and accurate results as well as the theories and rationale involved in HPLC method development. A system of quality checks was utilized as well as the validation of numerous developmental variables. By starting with a theoretical approach in preparation, extraction, and instrumental techniques and then further developing these practices by experimentation, a reproducible method was developed. Following the validation, fresh cascade hops grown in Sonoma County were analyzed during the 2017 harvest season and found to be within the predicted range specific to this cultivar. This method encompasses the techniques necessary to analyze fresh or dried hops, considering variability between different laboratories.

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Toxicity of the Hexane Fraction of Fruits and Seeds of Ricinus communis to Caterpillars of the Spodoptera Complex

et al. 2023

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The objective of this work was to evaluate the effect of the hexane fraction of the crude extract of the fruits and seeds of Ricinus communis (HFFSRC) on eggs of Spodoptera cosmioides and Spodoptera frugiperda and on caterpillars of Spodoptera eridania, S. frugiperda, and S. cosmioides, under laboratory conditions through topical application and ingestion, as well as to identify the compounds in the hexane fraction through high-performance chromatography (HPLC-ESI-Q-TOF-MS/MS). To do so, three bioassays were conducted: (1) the effect of HFFSRC at 2% (20,000 mg·mL−1) on eggs of S. cosmioides and S. frugiperda, (2) the lethal effect of HFFSRC at 2% applied topically, and (3) the lethal effect of HFFSRC at 2% applied to soybean-leaf discs on first-, second-, third-, and fourth-instar caterpillars of the three insect species. It was found that 2% HFFSRC had an ovicidal effect on S. frugiperda and S. cosmioides, completely reducing larvae hatching and the insecticidal effect for the four instars of the three insect species when applied topically and on food. Five compounds were identified in the HFFSRC: three flavonoids, one ricinoleic acid, and one cinnamic acid. HFFSRC at 2% had an acute ovicidal and insecticidal effect on caterpillars of the studied species, configuring itself as a potential insecticide.

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Ionic Samples: Reversed‐Phase, Ion‐Pair, and Ion‐Exchange HPLC

Cited by 3 publications

References 60 publications

Stability-Indicating Liquid Chromatography Method for Rifaximin and LC-MS Characterization of its Potential Degradants

Stability-Indicating Liquid Chromatography Method for Rifaximin and LC-MS Characterization of its Potential Degradants

Quantification of α-Acids in Fresh Hops by Reverse-Phase High-Performance Liquid Chromatography

Toxicity of the Hexane Fraction of Fruits and Seeds of Ricinus communis to Caterpillars of the Spodoptera Complex

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