1. Immunoaffinity enrichment and liquid chromatography-selected reaction monitoring mass spectrometry for quantitation of carbonic anhydrase 12 in cultured renal carcinoma cells
- Author
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Rafalko, Agnes, Iliopoulos, Othon, Fusaro, Vincent A., Hancock, William, and Hincapie, Marina
- Subjects
Mass spectrometry -- Methods ,Liquid chromatography -- Methods ,Enzymes -- Chemical properties ,Enzymes -- Identification and classification ,Cancer cells -- Chemical properties ,Cancer cells -- Composition ,Technology application ,Chemistry - Abstract
Liquid chromatography-selected reaction monitoring (LCSRM) is a highly specific and sensitive mass spectrometry (MS) technique that is widely being applied to selectively qualify and validate candidate markers within complex biological samples. However, in order for LC-SRM methods to take on these attributes, target-specific optimization of sample processing is required, in order to reduce analyte complexity, prior to LC-SRM. In this study, we have developed a targeted platform consisting of protein immunoaffinity enrichment on magnetic beads and LCSRM for measuring carbonic anhydrase 12 (CA12) protein in a renal cell carcinoma (RCC) cell line (PRC3), a candidate biomarker for RCC whose expression at the protein level has not been previously reported. Sample processing and LC-SRM assay were optimized for signature peptides selected as surrogate markers of CA12 protein. Using LC-SRM coupled with stable isotope dilution, we achieved limits of quantitation in the low fmol range sufficient for measuring clinically relevant biomarkers with good intra-and interassay accuracy and precision ([less than or equal to] 17%). Our results show that using a quantitative immunoaffinity capture approach provides specific, accurate, and robust assays amenable to high-throughput verification of potential biomarkers. 10.1021/ac101981t
- Published
- 2010