Highly sensitive detection for alkaline phosphatase using doped ZnS quantum dots with room temperature...

Area of Science:

• Materials Science
• Biochemistry
• Analytical Chemistry

Background:

• Alkaline phosphatase (ALP) is a crucial enzyme in biological processes.
• Developing sensitive and specific detection methods for ALP is vital for biomedical diagnosis.
• Room temperature phosphorescence (RTP) offers a sensitive detection modality.

Purpose of the Study:

• To develop a highly sensitive sensing system for alkaline phosphatase (ALP) detection.
• To utilize the room temperature phosphorescence (RTP) of Mn-doped ZnS quantum dots (QDs) for sensing.
• To investigate the mechanism of phosphorescence quenching by ALP.

Main Methods:

• Synthesis of Mn-doped ZnS quantum dots.
• Utilizing pyrophosphate and beta-cyclodextrin for QD aggregation control.
• Monitoring RTP quenching upon ALP addition.
• Optimization of sensing parameters.
• Validation with human serum samples.

Main Results:

• The sensing system exhibited intense RTP emission in the absence of ALP, which was quenched upon ALP addition.
• A linear detection range for ALP was established from 0.2-10 U/L.
• A low limit of detection (LOD) of 0.045 U/L was achieved.
• High recovery rates (93.75%-103.03%) were observed in human serum samples.
• Demonstrated an RTP-based "INHIBIT" logic gate functionality.

Conclusions:

• The developed Mn-doped ZnS QD system provides a sensitive and effective platform for ALP detection.
• The sensing mechanism involves ALP-mediated hydrolysis of pyrophosphate, altering QD aggregation and phosphorescence.
• The system shows significant potential for practical applications in biomedical diagnosis.