A 3D Biocompatible Plasmonic Tweezer for Single Cell Manipulation.

Area of Science:

• Biophysics
• Nanotechnology
• Cell Biology

Background:

• Plasmonic tweezers offer low power, wide operating range for particle manipulation.
• Trapping micron-sized objects, especially biological ones, remains a challenge for current plasmonic tweezers.

Purpose of the Study:

• To develop a 3D biocompatible plasmonic tweezer for single living cell manipulation in solution.
• To overcome limitations in trapping and manipulating larger biological objects with plasmonic tweezers.

Main Methods:

• Designed a tapered tip with a three-layer structure: nanoprobe, gold nanofilm, and thermosensitive hydrogel (thiolated poly(N-isopropylacrylamide)).
• Utilized incident light to excite surface plasmon polaritons, generating heat for hydrogel phase transition.
• Enabled reversible cell binding via functionalized surface and cell membrane interaction, minimizing thermal and mechanical stress.

Main Results:

• Achieved selective capture, 3D pathway-free transport, and controlled release of target cells.
• Demonstrated excellent biocompatibility, low energy consumption, and high operational flexibility of the developed plasmonic tweezer.
• Successfully manipulated single living cells in solution using the novel tweezer design.

Conclusions:

• The 3D biocompatible plasmonic tweezer effectively addresses challenges in manipulating micron-sized biological objects.
• This technology offers a promising tool for cell biology research and applications requiring precise cell handling.
• The device exhibits superior biocompatibility and operational flexibility for advanced cell manipulation tasks.