2,2-Dihydroxy-l,3-indandione

Ninhydrin (2,2-dihydroxy-l,3-indandione) Amax = 570 nm, Amax = 440 nm. This reagent has already been described earlier in this chapter (Sec. III.A. Ion Exchange). Additionally, it should be noted that ninhydrin reagent solutions are susceptible to photodegradation and air oxidation. Older solutions will yield progressively poorer response as the ninhydrin oxidizes. It is an arbitrary decision when to swap a new solution for the old. Representative references include 172-174. 

Dihydroxydiethylamine, d245 Af,Af-Di(hydroxyethyl)aminoacetic acid, bl82 2,2-Dihydroxy-l,3-indandione, il6... 

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