Fluorescent conjugates of Alpha-Bungarotoxin bind to the nicotinic acetylcholine receptor with high affinity, and thus can be used to image the distribution of the receptor at the neuromuscular junctions. CF® dyes are Biotium's line of next-generation fluorescent dyes with advantages in brightness, photostability, and conjugate specificity compared to other fluorescent dyes. Far-red fluorescent CF®633 has excitation/emission at 630/650 nm.