Compilation of an ESI-MS Library of β-Lactam Antibiotics for Rapid Identification of Drugs

β-Lactam antibiotics are among the most frequently used in clinical therapy. Thirty-three cephalosporin and eleven penicillin antibiotics frequently used in China have been used to create an ESI-MS library. A single-quadrupole mass analyzer was used for rapid identification. The product ions of these 44 β-lactam antibiotics were assigned to establish the fragmentation patterns and a standard ESI-MS library was established. Along with the specificity that product ion spectral information provides, the library provides another means to help identify β-lactam antibiotics. This is an important complement to the retention time from LC separations, and a valuable tool for confirming the identity of counterfeit drugs.