Nanofiber-based paramagnetic probes for rapid, real-time biomedical oximetry

Area of Science:

• Biomedical Engineering
• Materials Science
• Analytical Chemistry

Background:

• Electron paramagnetic resonance (EPR) oximetry is vital for measuring tissue oxygen levels, crucial for disease diagnosis and treatment.
• Existing EPR oximetry sensors face limitations in response time and biocompatibility for in vivo applications.

Purpose of the Study:

• To develop and characterize novel nanofiber-based sensors for enhanced EPR oximetry.
• To improve the speed and biocompatibility of oxygen sensing for biological and clinical applications.

Main Methods:

• Fabrication of core-shell nanofibers (LiNc-BuO-PDMS-PCL) via electrospinning, encapsulating Lithium octa-n-butoxynaphthalocyanine (LiNc-BuO) within PDMS and PCL.
• Characterization of sensor response to varying oxygen partial pressures (pO2) by measuring linewidth dependence.
• In vitro evaluation of sensor stability and biocompatibility using cultured cells.

Main Results:

• The LiNc-BuO-PDMS-PCL nanofiber sensors demonstrated a linear relationship between linewidth and pO2.
• Achieved significantly faster response (0.35 s) and recovery (0.55 s) times compared to previous chip sensors.
• Confirmed sensor stability and biocompatibility in in vitro cell exposure tests.

Conclusions:

• The developed core-shell nanofiber sensors offer a promising platform for rapid, accurate, and biocompatible EPR-based oximetry.
• The high porosity and oxygen permeability of nanofibers contribute to enhanced sensor performance.
• This technology holds potential for long-term and repetitive oxygen measurements in biological systems and clinical settings.