3D fluidic devices for detection and chemical analysis of analytes

Three-dimensional paper fluidic devices are made from a single sheet of material that transports liquids via capillary action. These devices have patterned channels and reservoirs for fluid flow, can detect specific chemicals, and may include electrodes for electrochemical analysis.

Background

Current methods for chemical analysis using microfluidic devices face significant challenges, particularly in resource-limited settings. Traditional two‑dimensional (2-D) microfluidic paper analytical devices (µPADs) involve patterning channels on paper using materials like photoresist or wax, but these devices are limited by their inability to effectively manage complex fluidic paths and multiple layers.

Three-dimensional (3-D) µPADs offer more advanced capabilities by stacking multiple layers, but their fabrication is labor-intensive, requiring sequential photolithographic steps and laser cutting to create fluidic connections between layers. Additionally, the assembly of these devices using double-sided tape is irreversible, limiting their functionality and reusability.

These constraints make the production process time-consuming, costly, and less adaptable for high-throughput or point-of-care applications, especially in underdeveloped regions where robust, low-cost, and easy-to-use diagnostic tools are critically needed.

Technology description

Three-dimensional paper fluidic devices are constructed from a single sheet of material that acts as a support layer capable of transporting liquids through capillary action. The support layer is patterned with channel walls using photoresist or wax materials to create impermeable barriers. These devices are assembled by folding the support layer into a compact, multi-layer structure, which can then be enclosed in an impermeable cover to prevent evaporation and contamination. Chemically sensitive particles can be embedded within the support layer to detect specific analytes, and the device may also include electrodes for electrochemical analysis and movable strips to control fluid flow. The folded structure allows for a compact and efficient design, making it suitable for various analytical applications.

The technology stands out due to its innovative use of origami principles to create a 3-D structure from a single sheet of material, significantly simplifying the fabrication process. Unlike traditional multi-layered microfluidic devices that require complex assembly and photolithography for each layer, this approach allows for rapid and cost-effective production.

The ability to fold and unfold the device enables parallel analysis across multiple layers, enhancing its utility for high-throughput screening and multiplexed detection. Additionally, the incorporation of chemically sensitive particles and electrodes within the paper matrix allows for versatile chemical and electrochemical analyses, making it a powerful tool for point-of-care diagnostics, especially in resource-limited settings.

Benefits

Compact, multi-layer structure formed by folding a single sheet of material
Capable of transporting liquids via capillary action
Patterned with channel walls using photoresist or wax materials to create impermeable barriers
Embedded chemically sensitive particles for detection of specific analytes
Enclosed in an impermeable cover to prevent evaporation and contamination
Includes electrodes for electrochemical analysis
Movable strips to control fluid flow
Fabrication from a single sheet reduces cost and speeds up the process
Device can be easily unfolded for parallel analysis
Useful for power-free, point-of-care detection and diagnosis
Can be used for high-throughput screening and multiplexed detection