Simultaneous separation and identification of antibiotic drugs in complex mixtures by using liquid chromatography-tandem mass spectrometry (LC-MS-MS).

Antibiotics are generally considered to be potential lifesaving drugs. In recent times it has been observed that these drugs are being used indiscriminately by many individuals, including youngsters and the elderly. It is well known that most drugs including antibiotics, can cause anaphylactic shock in certain individuals, and this can lead to forensic investigation because of the unexpected nature and abruptness of the death. It is important therefore to have an effective method for the identification of these antibiotic compounds in forensic samples. Earlier workers had performed the separation and identification of fluoroquinolone antibiotics by using various analytical techniques such as High Performance Thin Layer Chromatography (HPTLC), High Performance Liquid Chromatography (HPLC), and Gas Chromatography-Mass Spectrometry (GC-MS). In this study, a simple and selective qualitative method was developed for the separation and identification of four fluoroquinolone antibiotic drugs (Ciprofloxacin, Norfloxacin, Ofloxacin and Gatifloxacin) in forensic samples by using Liquid Chromatography-Tandem Mass Spectrometry (LC-MS-MS) by using Multiple Reaction Monitoring (MRM) functions. The limit of detection (LOD) was observed to be 10 ng/mL for Norfloxacin, Ciprofloxacin and Gatifloxacin, while it was 0.5 ng/mL for Ofloxacin.