AkaLumine (Aka Lumine) is a firefly luciferin analog that is a luciferase substrate that binds to Abeta aggregates and plaques.AkaLumine is used for in vivo optical imaging.

In LLC/luc and MDA-MB-231/Luc cells treated with AkaLumine, the signal began to peak at a lower concentration of 2.5 μM. In contrast, bioluminescence produced by D-luciferin and CycLuc1 continued to rise with increasing concentration and did not reach a significant saturation point even at the highest concentration of 250 μM. [1]

In a time course of bioluminescence production in vivo, AkaLumine displayed a stable glow-type reaction at various injection doses and its bioluminescence production remained elevated longer at the higher concentrations; this temporally more stable bioluminescence production may be beneficial for acquiring images without influence of acquisition time. Furthermore, AkaLumine has a relatively longer half-life (∼40 min) in serum. These results suggest that AkaLumine would be a suitable substrate for in vivo imaging. [1]