Our Rhodamine Red™-X conjugate of NeutrAvidin™ biotin-binding protein - a form of avidin that has been processed to remove carbohydrate and to lower its isoelectric point - can substantially decrease background due to nonspecific binding. The method used to deglycosylate the avidin retains its specific binding. This bright, red-fluorescent reagent (absorption/emission maxima ∼570/590 nm) is ideal for detecting biotinylated targets in fluorescence microscopy applications.