Role of sodium sulfite and β cyclodextrin as preservative of photographic developing agents

Para-aminophenol, N-methyl para-aminophenol sulfate and pyrogallol are used as photographic developer and their fluorescence intensity has been quenched in presence of acid, base, KCl, KBr, KI and oxygen. In presence of sodium sulfite fluorescence intensity of the compounds gradually increases with time. It has been established that in the steady-state fluorescence of these photographic developers the role of sodium sulfite is oxygen scavenger. In presence of β cyclodextrin, fluorescence intensity of these photographic developers increases due to steric restriction. Location and nature of the surrounding medium of the photographic developers in cyclodextrin have been ascertained from quenching study. The presence of two rotamers of aminophenols and substituted aminophenols has been established from fluorescence anisotropy study. The relative stability of the rotamers and the attachment of the compounds in the cavity of β cyclodextrin have been established on the basis of semiempirical AM1-SCI calculation.