Development of a homogeneous competitive immunoassay for phosphorylated protein antigen based on the enhanced...

Area of Science:

• Biochemistry
• Immunotechnology
• Molecular Biology

Background:

• Protein phosphorylation is a critical regulatory mechanism in cellular signaling.
• Existing methods for detecting phosphorylated proteins can be complex or lack sensitivity.
• Enhanced fluorescence resonance energy transfer (FRET) offers a sensitive platform for biomolecular detection.

Purpose of the Study:

• To develop a homogeneous competitive immunoassay for phosphorylated protein antigens.
• To leverage enhanced FRET technology for increased signal detection.
• To establish a sensitive and simple assay for quantifying phosphorylated extracellular signal-regulated kinase (ERK).

Main Methods:

• Development of a competitive immunoassay utilizing enhanced FRET.
• Construction of molecular probes conjugated with anti-phosphorylation site antibodies or antigen peptides.
• Utilizing the FRET signal change upon binding with phosphorylated antigens.
• Employing extracellular signal-regulated kinase (ERK) as a model phosphorylated protein.

Main Results:

• The assay demonstrated a significant change in fluorescent spectrum upon interaction with phosphorylated antigens.
• A concentration range of 15 nM to 250 nM for phosphorylated ERK was successfully determined.
• The assay showed high sensitivity and specificity for the target phosphorylated protein.

Conclusions:

• A novel, simple, and sensitive homogeneous competitive immunoassay for phosphorylated proteins was successfully developed.
• The enhanced FRET-based assay is suitable for quantifying phosphorylated ERK.
• The assay has potential applications in both in vitro diagnostics and in vivo detection of protein phosphorylation.