Graphene-based immunosensor for electrochemical quantification of phosphorylated p53 (S15)

Area of Science:

• Biomedical Engineering
• Biosensors
• Analytical Chemistry

Background:

• Phosphorylated p53 on serine 15 (phospho-p53(15)) is a potential biomarker for gamma-radiation exposure.
• Sensitive and reliable detection methods for phospho-p53(15) are crucial for monitoring radiation effects.

Purpose of the Study:

• To develop and optimize a graphene-based immunosensor for the electrochemical quantification of phospho-p53(15).
• To evaluate the sensor's performance, including sensitivity, stability, and reproducibility.

Main Methods:

• Fabrication of a graphene-based electrochemical immunosensor utilizing a sandwich immunoassay format.
• Immobilization of capture antibodies, antigen-antibody complex formation, and detection using horseradish peroxidase (HRP)-labeled streptavidin.
• Electrochemical detection based on the HRP-catalyzed reduction of hydrogen peroxide.

Main Results:

• The immunosensor demonstrated a linear response to phospho-p53(15) concentration in the range of 0.2-10 ng mL⁻¹.
• A low detection limit of 0.1 ng mL⁻¹ was achieved.
• The sensor exhibited acceptable stability and reproducibility, with results correlating well with known values.

Conclusions:

• The developed graphene-based immunosensor is a sensitive, stable, and reproducible tool for quantifying phospho-p53(15).
• This technology offers a promising approach for the analysis of phospho-p53(15) and other phosphorylated proteins, particularly in the context of radiation exposure monitoring.