FOR SECURITY PURPOSES - because Internet Explorer is no longer supported by Microsoft, we suggest that you interact with our secure site through one of our supported browsers - Google Chrome, Firefox, or MS Edge. If you continue to use this website with Internet Explorer you do so at your own risk and you may encounter problems.
This application note for the LC-UV assay and organic impurities for Alosetron hydrochloride is based on the USP monograph, which was validated using the Gemini 3 µm C18 column for both the assay (isocratic) and organic impurities (gradient).
Alosetron hydrochloride, a potent and selective antagonist of the serotonin 5-HT3 receptor, is the active pharmaceutical ingredient in Lotronex tablets, and there are several generic versions of Alosetron tablets available on the market. This application note for the LC-UV assay and organic impurities for Alosetron tablets is based on the official USP monograph, which was validated using the Gemini 3 µm C18 column for both the assay (isocratic) and organic impurities (gradient).
Both hair and oral fluid are difficult matrices to work with due to the sample preparation and chromatography challenges. Discover our method development solutions for these alternative matrices and how to solve these problems in your own lab.
This application note for the LC-UV assay and organic impurities for Vardenafil hydrochloride drug substance is based on the official USP monograph which calls for an L1 (C18) 5 µm, 250 x 3.0 mm column under gradient conditions for both assay and organic impurities. The mobile phase, standard solution, and system suitability solution for the assay and organic impurities were prepared in accordance with the USP monograph, using the USP Vardenafil hydrochloride reference standard and Vardenafil hydrochloride system suitability reference standard (containing 99% Vardenafil hydrochloride and 1% 7-Methylvardenafil). Vardenafil hydrochloride is a PDE-5 inhibitor and is the generic version of the brand name drug Levitra.
Enhancing the extraction of Vitamin A and E in serum using Simplified Liquid Extraction (SLE) significantly improves the LC-MS/MS detection of target compounds, all while preserving a simple and robust method.
In this technical note, we develop a simplified liquid extraction (SLE) application for THC and metabolites in urine in order to identify the optimum elution solvent from 7 different elution solvent variants. Results from each extraction were then compared based on recovery as well as a general baseline cleanliness in an effort to understand which solvent(s) is most suitable for this analysis.
Glyphosate is the most widely used herbicide globally and is of priority concern with many food and environmental agencies. Presented is an FMOC (Fluorenylmethyloxycarbonyl chloride) derivatization method using a reversed phase procedure.
One of the world's leading HPLC brands, now enhanced for incredible LC performance! Luna Omega 1.6µm, 3µm, and 5µm C18 HPLC/UHPLC columns culminate 20 years of technological advancements and innovation.
Loratadine is an antihistamine that can be administered through an oral solution. Because of the aromatic nature of the compound, we investigated a reversed phase method that leveraged the Kinetex 5 µm Biphenyl column. This column was selected because of its relative increased polar retention and aromatic selectivity
Since gabapentin is unmetabolized and excreted renally, it is found in high concentrations in urine. These high concentrations can make analysis of other compounds, specifically amphetamine, difficult due to overloading the LC column and saturating the source of the mass spectrometer. This work examines the most commonly used drug research panel method conditions and evaluate modifications that can be made to alleviate these issues for robust analysis of amphetamine in a high concentration gabapentin positive sample.
Cannabidiol (CBD) is a phytocannabinoid found in Cannabis, and a major focus of both pharmaceutical research and consumer products. CBD formed from within the plant is created by an enzyme-mediated process which exclusively forms the levorotatory isomer, (-)-cannabidiol, as has been confirmed by optical rotation and NMR analysis of plant extracted and purified material. The first synthetic approach to cannabinoids was based on the use of commercially available, chiral starting materials. This approach is still used in many pharmaceutical synthetic processes this day. For the development of plant-based cannabinoid products, having the ability to verify enantiomeric purity would be an excellent opportunity for quality verification of their products.
This technical note walks through the various considerations that need to be taken into account when working with polar basic compounds. Several UHPLC columns are compared including a Luna Omega Polar C18 and a Waters ACQUITY BEH C18 column.
This technical note walks through the various considerations that need to be taken into account when performing intact peptide analysis. Several UHPLC columns are compared including a Luna Omega C18 and PS C18 and a Waters ACQUITY BEH C18 column.
Analysts are increasingly relying upon LC-MS to perform their peptide and protein digest analyses, and TFA is not often used in conjunction with LC-MS due to its strong signal-suppression properties. Thus, when performing peptide analysis by LC-MS using typical mobile phases such as water/acetonitrile/formic acid, secondary interactions between basic amino acids on the peptide and the underlying silica can lead to broad peaks, peak tailing, and can interfere with optimal resolution between close-eluting peaks. To obtain optimal performance for peptide analysis using either LC-UV or LC-MS, the ideal media should be highly efficient (narrow peaks) and highly inert (minimal peak tailing when using MS-compatible modifiers like formic acid). In addition, a more retentive media is often favorable, particularly for peptide mapping, to maximize retention of small, polar peptide fragments that may not have a high affinity for a typical C18 phase, particularly in the absence of TFA (trifluoroacetic acid). Using this information, Luna Omega PS C18 and C18 were tested alongside a Waters ACQUITY UHPLC column.
Here we present a single high efficiency separation and analysis of common explosives, typically analyzed by EPA 8330A and 8330B. For such a mixture of related compounds, the Polar C18 stationary phase bonded to a Kinetex core-shell particle was chosen because of its high efficiency separation power alongside dual polar/non-polar selectivity that can greatly help to magnify small differences between similar compounds of interest.
This technical note walks through the various considerations that need to be taken into account when performing a general screening of pharmaceutical compounds. Several UHPLC columns are compared including a Luna Omega C18 and PS C18 and a Waters ACQUITY BEH C18 column.
This technical note walks through the various considerations that need to be taken into account when performing multi-class screening such as a pesticide panel. Several UHPLC columns are compared including a Luna Omega C18 and Polar C18 and a Waters ACQUITY BEH C18 column.