Optical fiber-based sensing method for nanoparticle detection through supervised back-scattering analysis: a...

Area of Science:

• Nanotechnology
• Biomedical Engineering
• Optical Physics

Background:

• Nanoparticle detection is vital for nanotechnology applications and understanding biological processes.
• Naturally occurring nanostructures like extracellular vesicles (EVs) and lipoproteins are important biomarkers for human health.
• Current methods struggle to detect nanoparticles below the diffraction limit, hindering early disease diagnosis.

Purpose of the Study:

• To investigate a novel method for detecting synthetic nanoparticles using optical fiber technology.
• To assess the accuracy and sensitivity of this technique for identifying nanoparticles similar in size to biological structures.

Main Methods:

• Utilized a polymeric lensed optical fiber tip to collect back-scattered laser light from nanoparticle solutions.
• Projected signal information into a lower dimensional space to create a discriminant function for detection.
• Tested the method with 100 nm synthetic nanoparticles at various concentrations in distilled water.

Main Results:

• Achieved 100% accuracy in detecting nanoparticles at concentrations ≥ 3.89 µg/mL (8.74E+10 particles/mL).
• Demonstrated 90% accuracy for concentrations between 1.22E-03 µg/mL (2.74E+07 particles/mL) and 3.89 µg/mL.
• The detected concentrations are comparable to physiological levels of EVs and lipoproteins in human plasma.

Conclusions:

• The proposed optical fiber technique can detect synthetic nanoparticles comparable in size to clinically relevant biological nanostructures.
• This method shows promise for developing innovative devices for detecting extracellular vesicles and other biological nanoparticles.
• The technique's sensitivity aligns with physiological levels of key biomarkers, supporting its potential for early disease diagnosis.