A very mild and selective approach to greatly improved properties of Pd oxazolones by site-incorporation on an enzyme is reported. The new Pd–enzyme conjugates were fluorescents at ppm concentrations excellent catalysts in different reactions.

Light transmission changes upon massive stimulation of single muscle fibers of Xenopus were studied with the potential-sensitive nonpermeant dyes, merocyanine rhodanine (WW375) and merocyanine oxazolone (NK2367). Upon stimulation an absorption change (wave a) occurred, which probably represents the sum of action potentials in the transverse tubules and surface membrane. In WW375-stained fibers ...