Two impurities were detected in the HPLC analysis of crude carbamazepine active pharmaceutical ingredient. One of the impurities of the order of 0.5% was found to be unknown and has not been reported previously. A LC-MS compatible reverse phase isocratic method was developed and tandem mass spectrometry was performed using electrospray ionization source and ion trap mass analyzer. Isolation of unknown impurity was performed by semi-preparative HPLC followed by characterization using nuclear magnetic resonance spectroscopy (NMR), infrared spectroscopy (FT-IR) and elemental analysis (CHNS) confirmed its structure as tetrabenzo[b,f,b'f']azepino[4',5':4,5]thieno[2,3-d]azepine-3,9-dicarboxamide. A plausible mechanism for the formation of this impurity is proposed.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1016/j.jpba.2011.05.030 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Characterizing the precursors of byproducts formed by chlorine and chlorine dioxide disinfection using unknown screening analysis with Orbitrap mass spectrometry.
Sci Total Environ
January 2025
Department of Environmental Engineering, Faculty of Engineering, Khon Kaen University, Khon Kaen 40002, Thailand; Research Center for Environmental and Hazardous Substance Management, Khon Kaen University, Khon Kaen 40002, Thailand. Electronic address:
Chlorine (Cl) and chlorine dioxide (ClO) are commonly used to disinfect water but unfavorable interactions with dissolved organic matter (DOM) result in the formation of disinfection byproducts (DBPs). This study investigated the formation of organic DBPs arising from Cl and ClO disinfections under different contact times in two surface waters in Thailand and Suwannee River natural organic matter with/without bromide using unknown screening analysis with Orbitrap mass spectrometry. Many CHOCl-DBPs and CHOBr-DBPs intermediates were rapidly formed during the initial period of contact (5-30 min).
View Article and Find Full Text PDFWorking with technical purity: simulation of red tattoo pigment metabolism by online-liquid chromatography-electrochemistry-mass spectrometry.
Anal Bioanal Chem
January 2025
Institute of Inorganic and Analytical Chemistry, University of Münster, Münster, Germany.
Tattooing is a popular form of body art that has evolved from ancient times into being part of modern society. The understanding of biotransformation processes of coloring tattoo pigments in human skin is limited although skin reactions to tattoos with unknown culprits occur. Electrochemistry coupled to mass spectrometry (EC-MS) has widely been used as a tool for a purely instrumental approach to simulating the enzymatic biotransformation of xenobiotics.
View Article and Find Full Text PDFOligoDistiller: A Platform Agnostic Software Tool for MS and MS Data Analysis of Complex Oligonucleotides and Their Impurities.
Anal Chem
December 2024
Janssen Pharmaceutica N.V., Turnhoutseweg 30, 2340 Beerse, Belgium.
Oligonucleotides are currently one of the most rapidly advancing classes of therapeutic modalities. Understanding critical quality attributes, such as the impurity profile, stability, potential metabolites, and sequence conformity, is the key to their ultimate success. To obtain the information presented above, liquid chromatography-mass spectrometry (LC-MS) is often employed.
View Article and Find Full Text PDFInvestigation of Spent Moulding Sand Using Thermal Treatment with Regard to the Possibility of Recovering Quartz Matrix.
Materials (Basel)
December 2024
Faculty of Materials, Metallurgy and Recycling, Technical University of Kosice, Letna 1/9, 042 00 Kosice, Slovakia.
The ongoing sustainable reduction in natural resources is prompting companies to look for materials to reuse that were previously classified as waste. Uses are sought for them either in their existing area of use or in other areas of the economy. In many cases, this is difficult.
View Article and Find Full Text PDFApplication of Advanced High-Resolution Mass Spectrometric Techniques for the Analysis of Losartan Potassium Drug Substance Degradation Products: From Nontargeted to Targeted Screening.
J Sep Sci
December 2024
NMPA Key Laboratory for Bioequivalence Research of Generic Drug Evaluation, Shenzhen Institute for Drug Control, Shenzhen, China.
Advances in techniques for quality analysis allow for a more detailed examination of drug impurities. High-resolution mass spectrometry (HRMS) contributes to detecting both known and unknown impurities. In this study, a combination of a nontargeted and targeted screening approach was established and applied to the detailed degradation profile of the losartan potassium (LP) drug substance.
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!