Microfluidic Devices with Integrated Controlled Magnetic Field Sources

The purpose of the work: To develop an effective technology for creating microfluidic chips for studying the dynamics of magnetic fluid media with non-magnetic inclusions using controlled exposure to magnetic field sources based on permanent magnets, electromagnets, and their combinations.

Metods. To consider several methods of manufacturing microfluidic chips based on a sandwich structure using Parafilm ® film, as well as PDMS microfluidics using a standard 3D printer, ABS plastic and acetone  The experiments were carried out on installations developed on the basis of known methods and equipment for magnetic measurements and manufactured independently. Various combinations of electric coils and permanent magnets are used as sources of an inhomogeneous magnetic field.

Results. An analytical review of known methods for the production of microfluidic chips was carried out. Most of them require expensive equipment and clean rooms, but a number of them are based on the use of available consumables and do not require specific conditions. These include technologies based on Parafilm® film, as well as PDMS chips with a removable ABS frame. For each of the technologies, a series of microfluidic chips was manufactured, during the production of which technological parameters changed: temperature, pressure and sintering time, the composition of the polymer matrix and the washing technology. The optimal production technology was determined on the basis of microscopic analysis and technological tests.

Conclusion. The paper considers several technologies for the production of microfluidic devices. Optimal parameters for manufacturing chips based on Plexiglass - Parafilm ® – Plexiglass sandwich structures have been determined. An original variant of manufacturing a microfluidic device with an integrated miniature magnetic field source based on ESCARGOT technology is proposed. The results obtained can be useful for the development of devices for controlled exposure to smart materials in microfluidic chips.

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