The significant enhancement of acidic potassium permanganate chemiluminescence by Mn(II) results from the concomitant presence of permanganate and Mn(III) in the reagent solution, which enables rapid production of the excited Mn(II) emitter with a wide range of analytes. Furthermore, the key Mn(III) co-reactant can be quickly generated by reducing permanganate with sodium thiosulfate, instead of the slow (∼24 h) equilibration required when Mn(II) is used. The emission from reactions with analytes such as tyrosine and fenoterol was over two orders of magnitude more intense than with the traditional permanganate reagent.