Micellar Ratiometric Fluorescent Blood pH Probe Based on Triplet-Sensitized Upconversion and Energy-Transfer...

Area of Science:

• Analytical Chemistry
• Biochemistry
• Materials Science

Background:

• Accurate pH measurement is crucial for understanding physiological and biochemical processes.
• Existing methods for pH detection can be limited by sensitivity, interference, or excitation wavelength requirements.

Purpose of the Study:

• To design and develop a novel micellar ratiometric fluorescent probe for sensitive and reliable pH detection.
• To utilize energy-transfer (ET) mechanisms for enhanced probe performance.
• To establish a new strategy for rapid and accurate *in vitro* blood pH monitoring.

Main Methods:

• A ratiometric fluorescent probe was engineered using a triplet-triplet annihilation upconversion (TTA-UC) system as the energy donor and p-nitrophenol (PNP) as the energy acceptor.
• The probe's pH-dependent energy transfer process was investigated.
• The probe's performance was evaluated in terms of sensitivity, selectivity, and anti-interference capabilities using serum samples.

Main Results:

• The designed probe exhibited pH-induced energy transfer from the TTA-UC system to PNP.
• Long-wavelength excitation was achieved due to the TTA-UC system, enabling ratiometric pH detection.
• The probe demonstrated high sensitivity to hydronium ions at nanomolar concentrations and excellent anti-interference properties in serum.

Conclusions:

• The novel TTA-UC/ET micellar probe provides a reliable and sensitive platform for ratiometric pH detection.
• This approach offers a significant advancement for rapid and accurate *in vitro* blood pH analysis.
• The probe's design overcomes limitations of traditional pH sensing methods.