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Dynamic Measurement of a Cancer Biomarker: Towards In Situ Application of a Fiber-Optic Ball Resonator Biosensor in CD44 Protein Detection

  • 0Laboratory of Biosensors and Bioinstruments, National Laboratory Astana, Nazarbayev University, 010000 Astana, Kazakhstan.
Sensors (basel, Switzerland) +

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March 28, 2024

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March 28, 2024

View abstract on PubMed

Summary

This summary is machine-generated.

This study introduces a novel optical fiber biosensor for real-time CD44 cancer biomarker detection. The developed biosensor achieves femtomolar sensitivity, offering a significant advancement for early cancer diagnosis and patient monitoring.

Area Of Science

  • Biomedical Engineering
  • Optical Sensing
  • Cancer Biomarkers

Background

  • Continuous monitoring of protein biomarkers is crucial for improving medical treatment accuracy.
  • Current cancer protein detection methods like ELISA are laborious, lack multiplexing, and offer only single-time point data.
  • There is a growing need for dynamic, sensitive, and real-time biosensing platforms for cancer biomarker identification.

Purpose Of The Study

  • To design, construct, and evaluate a single-mode optical fiber-based ball resonator biosensor for dynamic, in situ detection of the CD44 cancer biomarker.
  • To investigate the sensor's performance in a blood-mimicking environment, assessing sensitivity, specificity, and stability.
  • To advance the capabilities for early detection and continuous monitoring of solid malignant tumors.

Main Methods

  • Fabrication and calibration of an in-house optical fiber ball resonator biosensor.
  • In situ detection experiments using antibody-functionalized sensors with varying CD44 protein concentrations.
  • Optimization of sensor packaging and placement for performance in a blood-mimicking environment.
  • Assessment of sensor performance through static and dynamic calibration, pressure insensitivity tests, repeatability, specificity, and atomic force microscopy (AFM) surface morphology studies.

Main Results

  • The biosensor demonstrated consistent sensitivity to refractive index changes in both static and dynamic conditions.
  • Sensors were insensitive to pressure variations, confirming their utility for in situ measurements.
  • Optimized packaging and placement enhanced performance in a blood-mimicking environment.
  • Achieved a femtomolar detection limit (7.1 aM to 16.7 nM dynamic range) with nearly instantaneous signal changes.
  • Repeatability and specificity experiments confirmed the biosensor's reliability and selectivity for CD44.
  • AFM analysis indicated high sensitivity through significant height shifts without altered surface roughness.

Conclusions

  • The developed optical fiber ball resonator biosensor provides a dynamic, highly sensitive platform for real-time CD44 protein detection.
  • The sensor's femtomolar detection limit, specificity, and stability represent a significant advancement over existing methods.
  • This technology holds promise for improving the diagnosis, monitoring, and management of solid malignant tumors, enhancing patient health surveillance.

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