Anti-oxygen-quenching room temperature phosphorescence stabilized by deoxycholate aggregate.

Oxygen is the most effective dynamic quencher in liquid room temperature phosphorimetry (LRTP). Using oxygen scavenger to achieve significant or more sensitive RTP signals may bring about kinds of trouble in many cases and is apparently not very convenient in procedures. To date a few examples on LRTP without deoxygenation have been reported. Herein, we present a new named anti-oxygen-quenching RTP system using deoxycholate as a rigid medium. It can induce both lipophilic alpha-bromonaphthalene or 1-bromo-2-methylnaphthalene (BrMeN) and strongly water-soluble meso-tetrakis-(4-trimethylaminophenyl)porphyrin palladium (Pd-TAPP) to produce strong RTP emission under sodium deoxycholate of 4 mmol l(-1) and incubation time of half an hour. The maximum excitation and emission wavelengths respectively lie at 408 and 680 nm, with phosphorescence lifetime of 0.39 ms for Pd-TAPP, and at 285 and 515 nm, with lifetime of 4.9 ms for BrMeN. It is supposed that the hydrophobic and oxyphobic sandwich structure formed by two deoxycholate molecules with a phosphor in the case of deoxycholate or the interdiction fully of oxygen molecule diffusion into the microenvironment where the phosphor exists in the case of cyclodextrin is a key factor in inducing anti-oxygen-quenching RTP.