Trapping and Detection of Nanoparticles and Cells Using a Parallel Photonic Nanojet Array

Area of Science:

• Nanoscience
• Optical Physics
• Biotechnology

Background:

• Advanced nanoscience requires high-throughput, selective methods for trapping and detecting nanoscale objects.
• Current optical techniques struggle to achieve nanoscale resolution and selectivity for small particles.
• Extending micrometer-sized object manipulation to the nanoscale remains a significant challenge.

Purpose of the Study:

• To develop a method for trapping and detecting nanoparticles and subwavelength cells at low optical power.
• To create a parallel array of nanotraps with high resolution and selectivity.
• To demonstrate the utility of the developed system for real-time detection and selective manipulation.

Main Methods:

• Assembling microlenses on an optical fiber probe to create a parallel photonic nanojet array.
• Utilizing the subwavelength confinement of photonic nanojets to form three-dimensional nanotraps.
• Detecting backscattering signals in real time with single-nanoparticle resolution.
• Demonstrating selective trapping from particle mixtures and biological samples.

Main Results:

• Formation of tens to hundreds of three-dimensional nanotraps using the photonic nanojet array.
• Real-time detection of backscattering signals with single-nanoparticle resolution and 10^3-10^4 enhancement factors.
• Successful selective trapping of nanoparticles and cells from mixed solutions and human blood.

Conclusions:

• The photonic nanojet array offers a powerful tool for nanoscale trapping and detection at low optical power.
• The technology enables high-throughput, single-nanoparticle resolution and high selectivity.
• Potential applications include nanoparticle assembly, biosensing, single-cell analysis, and optical sorting.