A biosensor-integrated filtration device for nanoparticle isolation and label-free imaging

Area of Science:

• Biotechnology
• Nanotechnology
• Medical Diagnostics

Background:

• Effective nanoparticle recovery from biological fluids is crucial for diagnostics, especially in resource-limited settings.
• Traditional methods like ultracentrifugation are often inaccessible in such environments.
• There is a need for simple, rapid, and efficient sample processing techniques.

Purpose of the Study:

• To develop and characterize a novel filtration device for recovering intact nanoparticles and viruses from bodily fluids.
• To evaluate the efficiency of this device in conjunction with a photonic crystal biosensor and PRISM instrument.
• To enable low-cost, portable diagnostic solutions.

Main Methods:

• Utilized a nanoporous filtration device to separate nanoparticles (100-200 nm diameter) from plasma.
• Employed a biosensor-integrated recovery device (BIRD) for nanoparticle collection.
• Characterized collection efficiency using gold nanoparticles (AuNP), fluorescent nanobeads, and HIV pseudovirus in buffer and human plasma.
• Detected filtered nanoparticles and virions using photonic resonator interferometric scattering microscopy (PRISM).

Main Results:

• Demonstrated recovery rates of 55.0% for 100 nm AuNP and HIV in buffer.
• Achieved an 11.9% recovery rate for 100 nm fluorescent nanobeads in human plasma.
• Observed Brownian motion and concentration-dependent contact events of nanoparticles and virions on the biosensor surface using PRISM.

Conclusions:

• The BIRD offers a simple and efficient method for biological nanoparticle recovery from bodily fluids.
• This approach facilitates the translation of lab-based diagnostics to low-resource settings.
• The integration with PRISM allows for sensitive detection of recovered nanoparticles and virions.