We are looking after a retrograde tracer like Fluorogold who is able to label neurons projecting to the portal blood like in this publication

Article Neurons with access to the general circulation in the centra...

Unfortunately, we cannot use the fluoroGold due to the emission wavelenght which is similar to another of our neuronal endogenous markers.

I have read that the FluoroRuby has the same properties than the FluoroGold but I didn't succeed so far to find any information about potential ip injection that will allow us to visualize in the brain the neurons that are projecting to the portal blood....

Thus does anyone know or have already use the FluoroRuby to retrogradely tract tracing neurons that project to the general circulation?