Highly Sensitive and Reliable microRNA Detection with a Recyclable Microfluidic Device and an Easily Assembled SERS...

Area of Science:

• Analytical Chemistry
• Nanotechnology
• Biotechnology

Background:

• Surface-enhanced Raman spectroscopy (SERS) offers high sensitivity and miniaturization for microfluidic detection.
• Challenges in SERS microfluidics include signal reproducibility, sensitivity, and device reusability.
• Existing SERS microfluidic devices face issues with contamination and complex cleaning procedures.

Purpose of the Study:

• To develop a repeatable SERS-based microfluidic device with a disposable substrate and reusable channel.
• To address limitations in sensitivity, reproducibility, and reusability of current SERS microfluidic systems.
• To enable sensitive and reliable detection of target molecules, such as micro-RNA.

Main Methods:

• Fabrication of a reusable microfluidic channel using mechanical processing.
• Creation of a disposable SERS substrate via nanoimprint lithography and electrodeposition.
• Assembly of the SERS substrate and microfluidic channel using screws for easy attachment.

Main Results:

• The SERS substrate achieved an enhancement factor >10⁸ with large-area uniformity and high reproducibility.
• The device demonstrated reliable and sensitive signals across multiple experiments.
• Successful detection of micro-RNA (miR-34a) at concentrations as low as 5 fM was achieved.

Conclusions:

• The developed SERS microfluidic device offers a repeatable and sensitive platform for molecular detection.
• The disposable substrate design simplifies cleaning and enhances commercial viability.
• This technology shows promise for precise analysis of biomarkers like micro-RNA.