Quantification of HER2 in COS7 cells using quantum weak measurement

Area of Science:

• * Biophotonics and Molecular Diagnostics
• * Interferometry and Weak Measurement Techniques

Background:

• * Accurate quantification of specific molecules like human epidermal growth factor receptor 2 (HER2) is crucial for cancer diagnosis and treatment.
• * Existing methods for molecular detection can be complex or lack sensitivity for certain applications.

Purpose of the Study:

• * To develop and validate a sensitive method for real-time monitoring and quantification of molecular concentrations.
• * To establish a technique for determining the number of HER2 receptors on cancer cells using weak measurement.

Main Methods:

• * A Mach-Zehnder interferometer system was employed, utilizing weak measurement principles.
• * Phase differences in optical paths were measured to detect concentration variations.
• * The concentration of trastuzumab (Herceptin) targeting HER2 was monitored by analyzing light spectrum changes.

Main Results:

• * The system successfully monitored the concentration of trastuzumab in real-time.
• * HER2 receptor numbers on COS7 cells were quantified at pico-molar sensitivity.
• * The phase difference changes directly correlated with molecular concentration variations.

Conclusions:

• * Weak measurement-based interferometry offers a sensitive and alternative approach for molecular concentration detection.
• * This technique provides a promising tool for quantifying HER2 in cancer cells, aiding in diagnosis and treatment.
• * The study demonstrates the potential of interferometric weak measurement in sensitive biomolecule quantification.