Novel active micromixer platform based on Lorentz force for lab-on-a-chip application

TL;DR

This paper presents a novel active micromixer utilizing Lorentz force for lab-on-a-chip applications, achieving high mixing efficiency and reproducibility through innovative fabrication and actuation techniques.

Contribution

The study introduces a new Lorentz force-based actuation method for micromixing, demonstrating high efficiency and reproducibility in a compact, easily fabricated device.

Findings

Mixing efficiency exceeds 95%

Device fabrication and operation are highly reproducible

Simulations confirm uniform temperature distribution

Abstract

Mixing in an active micromixer was achieved using Lorentz force-assisted actuation of an enameled copper wire. A single-step template-assisted soft lithography technique was used to construct the mixing chamber. The chamber had a volume of 1.86{\mu}l. Application of a Square wave alternating current in tandem with tension in the wire provided the necessary conditions for the resonant oscillation frequency of the wire. The repeatability of the ratio of higher harmonics to the fundamental frequencies of the oscillating wire conforms to standardization of the device fabrication, assembly, and functionality. Simulations and experiments were performed to validate uniform temperature distribution in the mixing chamber. Real-time optical detection of the sample assisted in sensing the completion of chemical reactions in the chamber. Mixing of various aqueous based chemical reactions was performed. It was found that mixing efficiency was greater than 95 percent. Multiple devices were fabricated to show the usability and reproducibility of the system.