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

Area of Science:

• Analytical Chemistry
• Photochemistry

Background:

• Oxygen is a major quencher in liquid room temperature phosphorimetry (LRTP), necessitating deoxygenation for sensitive signals.
• Existing methods for oxygen scavenging in LRTP can be inconvenient and problematic.

Purpose of the Study:

• To develop a new anti-oxygen-quenching system for LRTP that avoids deoxygenation.
• To investigate the use of deoxycholate as a rigid medium to enhance RTP signals.

Main Methods:

• A novel anti-oxygen-quenching RTP system was developed using sodium deoxycholate as a rigid medium.
• The system was tested with both lipophilic (alpha-bromonaphthalene, 1-bromo-2-methylnaphthalene (BrMeN)) and water-soluble (meso-tetrakis-(4-trimethylaminophenyl)porphyrin palladium (Pd-TAPP)) phosphors.
• Optimized conditions involved 4 mmol L(-1) sodium deoxycholate and a 30-minute incubation period.

Main Results:

• Strong RTP emission was achieved for both BrMeN and Pd-TAPP without deoxygenation.
• Pd-TAPP showed maximum excitation/emission at 408/680 nm with a lifetime of 0.39 ms.
• BrMeN exhibited maximum excitation/emission at 285/515 nm with a lifetime of 4.9 ms.

Conclusions:

• Deoxycholate creates a hydrophobic and oxyphobic microenvironment, preventing oxygen quenching.
• This anti-oxygen-quenching system offers a simpler and more convenient approach for LRTP analysis.