Rotigotine behenate (RGTB), a long chain alkyl ester of the prodrug of rotigotine (RGT), has been synthesized for use in a sustained delivery system. The aim of the present report was to develop and validate a simple, sensitive and reliable LC-MS/MS method for the simultaneous determination of RGT and its prodrug RGTB in rat plasma samples. Detection was performed on a 1290 Infinity UPLC coupled Triple Quad 4500 mass spectrometer operated in positive MRM mode using an Eclipse XDB-CN chromatography column (2.1mm×100mm, 3.5μm) by isocratic elution using a 0.2% formic acid aqueous solution and acetonitrile, with stable isotope labeled RGT as an internal standard. The sample preparation method employed 50μL of a plasma sample and liquid-liquid extraction with a mixture of diethyl ether-dichloromethane (3:2, v/v) as the extraction solvent. The proposed method was fully validated by assessing its specificity, linearity, precision and accuracy, recovery, matrix effects and stability. Good linearity was found within the range of 0.1-10.0ng/mL for both analytes (r>0.996). This method was successfully applied to a pharmacokinetic study of a slow release RGTB formulation in rats following a single intramuscular injection and biological conversion in vitro.
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http://dx.doi.org/10.1016/j.jpba.2017.07.018 | DOI Listing |
Clin Chim Acta
January 2025
Fundación Instituto de Investigación Sanitaria Islas Baleares (IdISBa), Hospital Universitario Son Espases, Carretera de Valldemossa, 79, 07010, Palma, Spain.
24-h urinary free cortisol (UFC) measurements are fundamental in the diagnosis and follow-up of Cushinǵs syndrome (CS) and immunoassays (IA) are the most widely used tests for its quantification in clinical laboratory practice. However, their suitability has been questioned mainly due to their limitations concerning analytical specificity. The aim of this research project was to evaluate a novel algorithm for CS diagnosis and follow-up in the clinical laboratory, based on the combination of IA tests with liquid chromatography-tandem mass spectrometry (LC-MS/MS) for UFC quantification.
View Article and Find Full Text PDFEBioMedicine
January 2025
State Key Laboratory of Molecular Oncology, CAMS Key Laboratory of Translational Research on Lung Cancer, Department of Medical Oncology, National Cancer Centre/National Clinical Research Centre for Cancer/Cancer Hospital, Chinese Academy of Medical Sciences Peking Union Medical College, Beijing, 100021, China. Electronic address:
Background: Small cell lung cancer (SCLC) represents a highly aggressive neuroendocrine tumour with a dismal prognosis. Currently, the identification of a specific tumour antigen that can facilitate immune-based therapies for SCLC remains elusive.
Methods: We employed liquid chromatography-tandem mass spectrometry (LC-MS/MS) to analyse cancer/testis antigens (CTAs) in SCLC cell lines and human tumour specimens.
Environ Sci Process Impacts
January 2025
Massachusetts Institute of Technology, Department of Civil and Environmental Engineering, Parsons Laboratory, 15 Vassar Street, Cambridge, Massachusetts 02139, USA.
The high salinity and organic content in oil and gas wastewaters can cause ion suppression during liquid chromatography mass spectrometry (LC/MS) analysis, diminishing the sensitivity and accuracy of measurements in available methods. This suppression is severe for low molecular weight organic compounds such as ethanolamines (, monoethanolamine (MEA), diethanolamine (DEA), triethanolamine (TEA), -methyldiethanolamine (MDEA), and ,-ethyldiethanolamine (EDEA)). Here, we deployed solid phase extraction (SPE), mixed-mode LC, triple quadrupole MS with positive electrospray ionization (ESI), and a suite of stable isotope standards (, one per target compound) to correct for ion suppression by salts and organic matter, SPE losses, and instrument variability.
View Article and Find Full Text PDFJ Mass Spectrom
February 2025
FTMS Laboratory for Human Health Research, Department of Chemistry, North Carolina State University, Raleigh, North Carolina, USA.
Perfluoroalkyl and polyfluoroalkyl substances (PFAS) are a class of emerging contaminants that have been in use industrially since the 1940s. Their long-term and extensive commercial use has led to their ubiquitous presence in the environment. The ability to measure the bioconcentration and distribution of PFAS in the tissue of aquatic organisms helps elucidate the persistence of PFAS as well as environmental impacts.
View Article and Find Full Text PDFAnticancer Agents Med Chem
January 2025
Department of Medical Biochemistry, Faculty of Medicine, Gaziantep University, 27410, Gaziantep, Turkey.
Background: The lung cancer is the leading cause of death worldwide. Although methods such as surgery, chemotherapy, radiotherapy, and immunotherapy are used for treatment, these treatments are sometimes inadequate. In addition, the number of chemotherapeutic agents used is very limited, and it is very important to use new natural agents that can increase the effect of these methods used in treatment.
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