Quantification of 16 cephalosporins in the aquatic environment by liquid chromatography‐tandem mass spectrometry

Abstract

Antimicrobial agents are essential to protect human and animal health. During the coronavirus disease 2019 pandemic, antimicrobials such as cephalosporins were widely used as prophylactics and to prevent bacterial co-infection.Undoubtedly, the prevalence of antibiotics in the aquatic environment will ultimately affect the degree of resistance against these bacteria in animals and the environmental systems. In order to monitor 16 cephalosporins in the aquatic environment, we developed a new liquid chromatography-tandem mass spectrometry method that functioned simultaneously under positive and negative electrospray ionization switching modes. The chromatographic separation has been implemented using a pentafluorophenyl propyl column kept at 40 • C. The limits of detection and quantitation for the studied cephalosporins ranged from (8 × 10 −4 ) to (7.11 × 10 −2 ) ng/ml and from (2.61 × 10 −3 ) to (2.37 × 10 −1 ) ng/ml, respectively. The percent extraction efficiency (apparent recovery) and relative standard deviations for the analyzed cephalosporins ranged from 61.69% to 167.67% and 2.45% to 13.48%, respectively. The overall findings showed that the effluent from the wastewater treatment plants that receive wastewater from pharmaceutical factories had a higher detected amount of cephalosporins than that of domestic sewage. Moreover, seven cephalosporins, including cefuroxime, ceftazidime, cefradine, cefprozil, cefixime, cefalexin, and cefadroxil (0.68-105.45 ng/L) were determined in the aquatic environment.

Identification and quantification of nine compounds in Fangwen Jiuwei decoction by liquid chromatography–mass spectrometry

“…To date, the identification of active components of Chinese medicines was usually conducted by microscopic identification [14], HPLC fingerprinting [15], DNA and molecular marker analysis [16], infrared spectroscopy [17], TLC [18], and LC‐MS/MS. LC‐MS/MS is a powerful analytical tool that enables the rational separation, identification, and quantification of unknown and known compounds in medicine [19]. LC‐MS/MS has strong selectivity, high sensitivity, and good separation ability for the mixtures of various compounds.…”