Novel PFAS Reverse Surrogates for TOP Assay Analysis

CIL is very pleased to announce three new novel reverse surrogates for use in TOP assay analysis. TOP assay oxidizes unknown PFAS precursors and intermediates into terminal PFAS that can be quantified by targeted LC-MS/MS methods such as US EPA Method 1633A.

Unfortunately, previously available surrogates used to measure the oxidation process interfered with targeted method analytes and internal standards. To alleviate this issue, CIL has teamed up with researchers to develop all new stable isotope-labeled surrogates that do not interfere with the target PFAS, extracted internal standard (EIS), or non-extracted internal standard (NIS) found in US EPA Method 1633A.

Included in these novel surrogate standards for us in TOP assay are:

• ¹³C₃-PFHpSA is used as a reverse surrogate which is transformed to ¹³C₃-PFHpA during the oxidation process
• ¹³C₃-PFHpA is used to quantify oxidation efficiency by measuring the formation of ¹³C₃-PFHpA
• ¹³C₃-PFNA does not undergo transformation during oxidation, so it can be used as a recovery standard to measure overall method efficiency

➤ PFAS Standards to TOP Assay Analysis
➤ Per- and Polyfluoroalkyl Substances (PFAS)
➤ Ultrashort-chain PFAS Standards