Metallic micro-ring device for highly efficient large cargo delivery in mammalian cells using infrared light pulses

Area of Science:

• Biomedical Engineering
• Cell Biology
• Nanotechnology

Background:

• Efficient and uniform delivery of biomolecules into live cells is crucial for biological research and biomedical applications.
• Existing methods often face challenges with delivery efficiency, cell viability, or scalability.

Purpose of the Study:

• To develop a novel device for highly efficient and uniform intracellular delivery of a wide range of biomolecules into diverse cell types.
• To demonstrate the efficacy of the titanium micro-ring (TMR) device using infrared (IR) light pulse activation.

Main Methods:

• Fabrication of a titanium micro-ring (TMR) array device with specific dimensions (10 μm outer diameter, 3 μm inner diameter, 10 μm interspacing).
• Activation of the TMR device using infrared (1050 nm) pulse laser irradiation to generate photothermal cavitation bubbles.
• Delivery of various biomolecules (propidium iodide, dextran, siRNA, plasmid DNA, β-galactosidase enzyme) into different cell lines (SiHa, L929, N2a).

Main Results:

• The TMR device achieved high delivery efficiency (∼96%) and cell viability (∼97%) for small molecules like propidium iodide.
• Successful transfection of plasmid DNA with ∼85% efficiency and ∼90% cell viability was observed in SiHa cells.
• Intracellular delivery of β-galactosidase enzyme was confirmed with ∼83% co-staining, indicating successful delivery of large biomolecules.

Conclusions:

• The TMR device enables efficient, uniform, and gentle intracellular delivery of diverse biomolecules across various cell types.
• The photothermal cavitation mechanism offers a promising approach for enhancing cellular uptake with high cell viability.
• This technology holds significant potential for advancing cellular diagnostics and therapeutic applications.