L-Serine, glycyl-L-arginylglycyl-L-α-aspartyl-, 2,2,2-trifluoroacetate (1:1)

Gly-Arg-Gly-Asp-Ser (TFA) is a pentapeptide that forms the cell-binding domain of a glycoprotein, osteopontin[1]. Gly-Arg-Gly-Asp-Ser binds to integrin receptors αvβ3 and αvβ5 with estimated IC50 of ～5 and ～6.5 μM[2].

[1] Kim GH, et al. Evaluation of Osteoblast-Like Cell Viability and Differentiation on the Gly-Arg-Gly-Asp-Ser Peptide Immobilized Titanium Dioxide Nanotube via Chemical Grafting. J Nanosci Nanotechnol. 2016 Feb;16(2):1396-9. DOI:10.1166/jnn.2016.11916
[2] Bernhagen D, et al. High-Affinity RGD-Knottin Peptide as a New Tool for Rapid Evaluation of the Binding Strength of Unlabeled RGD-Peptides to αvβ3, αvβ5, and α5β1 Integrin Receptors. Anal Chem. 2017 Jun 6;89(11):5991-5997. DOI:10.1021/acs.analchem.7b00554