FTISADTSK acetate(Cat No.:I044229)is a synthetic peptide composed of the amino acid sequence Phe-Thr-Ile-Ser-Ala-Asp-Thr-Ser-Lys, typically supplied as an acetate salt to improve solubility and stability. This peptide is commonly used in proteomics and mass spectrometry studies as a standard for calibration, quantification, or method validation. Its sequence contains both hydrophobic and polar residues, allowing for predictable chromatographic behavior and ionization efficiency. FTISADTSK is particularly valuable in enzymatic digestion studies, especially with trypsin, due to its C-terminal lysine, making it a reliable model peptide for peptide mapping and protein characterization workflows.