Figure 1
From: Analysis of fluorescently labeled substance P analogs: binding, imaging and receptor activation
Fluorescent SP analog structures. A) Alexa 488-SP, B) BODIPY Fl-SP, C) fluorescein-SP, D) Oregon Green 488-SP and E) tetramethylrhodamine-SP. The first 5 amino acids of SP (Arg1-Pro2-Lys3-Pro4-Gln5) are shown, with each of the fluorophores conjugated to Lys3. R = Gln6-Phe7-Phe8-Gly9-Leu10-Met11-NH2. Alexa 488 is the most charged structure, BODIPY Fl is the smallest, and Alexa 488 and tetramethylrhodamine are the largest.