Surface Charge-Reversible Tubular Micromotors for Extraction of Nucleic Acids in Microsystems

Area of Science:

• Microsystems Engineering
• Biomedical Microdevices
• Nucleic Acid Purification

Background:

• Nucleic acid extraction in microsystems is crucial for biomedical applications.
• Current methods often require complex microchannels and external equipment, limiting practical use.
• There is a need for simpler, more efficient microsystem-based nucleic acid extraction technologies.

Purpose of the Study:

• To develop a simple, versatile, and efficient method for nucleic acid extraction in microsystems.
• To utilize cationic branched polyethyleneimine (PEI)-functionalized tubular micromotors for this purpose.

Main Methods:

• Fabrication of tubular micromotors via template-assisted electrodeposition and carbodiimide chemistry.
• Micromotors incorporate catalytic Pt, magnetic Ni, and PEI layers for autonomous motion and nucleic acid binding.
• Utilized pH-dependent surface charge modulation for selective nucleic acid absorption and desorption.

Main Results:

• Demonstrated autonomous, magnetically guided motion of PEI-functionalized micromotors in hydrogen peroxide solutions.
• Achieved efficient nucleic acid extraction through reversible absorption (acidic pH) and desorption (alkaline pH).
• Successfully operated the micromotor system within a microchannel chip without external pumping.

Conclusions:

• The PEI-functionalized tubular micromotor platform offers a novel, simple, and efficient microsystem nucleic acid extraction technology.
• This approach eliminates the need for external stirring and complex pumping systems.
• The technology shows significant promise for practical applications in biomedical fields.