Background: Lactam cyclized alpha-melanocyte stimulating hormone (α-MSH) analogues exhibit high stability and affinity for the MC1-R receptors over expressed in melanoma cells. Recently, we reported a novel 99mTc-HYNIC-cycMSH4-13 analogue with the HYNIC chelator directly attached to the lactam cyclized ring. Keywords: HYNIC, α-MSH, 99mTc, melanoma, Ahx, tumor.
