A redox-regulated inner filter effect between Ti₃C₂ quantum dots and MnO₂ nanosheets for sensitive alkaline...

Area of Science:

• Materials Science
• Analytical Chemistry
• Biotechnology

Background:

• Alkaline phosphatase (ALP) is a crucial enzyme and disease biomarker.
• Accurate ALP detection is vital for clinical diagnosis.
• Existing detection methods may lack sensitivity or practicality.

Purpose of the Study:

• To develop a novel and sensitive fluorescent assay for alkaline phosphatase (ALP) detection.
• To utilize the redox-regulated inner filter effect (IFE) between Ti3C2 MXene quantum dots (Ti3C2 QDs) and MnO2 nanosheets for ALP sensing.
• To demonstrate the practicality of the developed assay in real biological samples.

Main Methods:

• Synthesis of blue-emitted Ti3C2 QDs via a top-down method.
• Construction of a Ti3C2 QDs/MnO2 nanosystem leveraging the inner filter effect (IFE).
• Development of a fluorescence turn-on assay based on ALP-catalyzed hydrolysis of AAP and subsequent redox reaction.

Main Results:

• The Ti3C2 QDs/MnO2 nanosystem exhibited efficient fluorescence quenching and recovery.
• The assay demonstrated a wide linear range (0.05-10 mU/mL) for ALP detection.
• A low detection limit of 0.014 mU/mL was achieved, with successful application in real biological samples.

Conclusions:

• A novel, sensitive, and practical fluorescent assay for ALP detection was successfully developed.
• The Ti3C2 QDs/MnO2 nanosystem shows significant potential for ALP sensing applications.
• This work expands the utility of MXene QDs in the field of biosensing.