Synthesis and labeling of p-NH2-Bn-DTPA-(Dabcyl-Lys6,Phe7)-pHBSP with 99mTc as a radiopeptide scintigraphic agent to detect cardiac ischemia

Myocardial ischemia and infarction represent a major health burden worldwide, but their immediate diagnosis can reduce mortality and healthcare costs. Pyroglutamate helix B surface peptide (pHBSP) derived from erythropoietin have shown tissue-protective effects in the ischemic situation by binding to erythropoietin receptor–Beta common receptors)EPOR–βcR(. This research aimed to synthesize and biologically evaluate p-NH2-Bn-DTPA-(Lys-Dabcyl6,Phe7)-pHBSP for cardiac ischemia imaging. Radiolabeling yielded more than 97%, and radiolabeled peptide showed significant binding affinity to H9c2 hypoxic cells (p < 0.001). A considerable accumulation of 99mTc-p-NH2-Bn-DTPA-(Lys-Dabcyl6,Phe7)-pHBSP was detected in the ischemic region by biodistribution study and SPECT/CT scintigraphy (3.84 ID/g% at 30 min).