As a follow up to the Application Note on detection of pharmaceuticals and personal care products (PPCPs) in water using the Agilent 6495 Triple Quadrupole Mass Spectrometer 8 , this Application Note describes two methods to screen and quantitate PPCPs in water at part per trillion (ppt) levels using the Agilent 6545 Q - TOF LC/ MS System. Similarly, the methods were divided into positive ion mode and negative ion mode due to the unique mobile phases used for the two methods. The precise and accurate screening and quantitation of 118 compounds in positive ion mode and 22 compou nds in negative mode was accomplished on the 6545 Q - TOF LC/MS using the Swarm tune parameters optimized for small fragile organic molecules. The high sensitivity slicer mode was selected to maximize instrument sensitivity. Most of the PPCPs could be det ected without tedious analyte enrichment such as solid phase extraction (SPE). The extent of sample preparation included filtering approximately 3 mL of sample, adding internal standards to a 1.0 mL aliquot of the filtered sample, and injecting 40 L of sample for analysis by Q - TOF LC/MS with reporting limits for the majority of analytes at 10 ppt. The limit of detection (LOD) and lower limit of quantitation (LLOQ) for most of the analytes are much lower than 10 ppt Agilent 6545 四極桿飛行時(shí)間液質(zhì)聯(lián)用系統(tǒng)