(142c) Magnetic Particle Sorting in Microfluidic Devices Fabricated Via Femtosecond Laser Ablation with Surface Modification

We have developed microfluidic devices fabricated by laser ablation for magnetic particle bioassays. Femtosecond laser ablation offers a rapid prototyping method for microfluidic devices in a non-cleanroom setting. Our process involves machining features by laser ablation followed by surface modification to tune roughness and surface properties. Laser ablation can be used on a broader range of materials than traditional microfabrication, including glass, polymers, metals, and ceramics. Magnetic particle bioassays are a good test platform because magnetic assays are highly sensitive to roughness (particle entrapment), surface chemistry (non-specific binding of biomolecules), and electrical properties (electrophoresis, electrokinetic flow). We are using magnetic particles to analyze the effects of these properties on magnetic bioassay performance. We are also modeling and studying scale-down parameters for purposes of shrinking devices to improve separation efficiency.