Autonomous Self-Regulating Microfluidic System

 

This technology enables the fabrication of microfluidic devices that automatically maintain homeostasis via an organic feedback system. Originally developed to create self-regulating pH systems, this technology can be used to create medical/biological devices that self-govern temperature, light, molecular, and other fluid parameters.

Most microfluidic devices designed to maintain homeostasis use feedback systems based on electronics or other non-biologically compatible actuation methods. To overcome the limitations of those devices, this technology uses a responsive polymeric material hydrogel as the control system. According to its chemistry, the hydrogel expands when exposed to a given condition (e.g., high pH) and constricts in the opposite condition (e.g., low pH). As the hydrogel expands and contracts, it deforms a 30 m polydimethylsiloxane membrane that regulates the feedback stream. The hydrogel's chemistry is selected according to the fluid parameter of interest. In this way, the microfluidic device operates without electronics or external power, allowing it to be used in medical and biological applications. Construction of the device, which involves compression micromolding, layered manufacturing, and in situ liquid phase polymerization, can be completed in one day and is less expensive than other manufacturing techniques for microfluidic systems.

Advantages

These new technologies enable the fabrication of innovative microfluidic devices that address many of the limitations associated with conventional systems:

  • Unlike silicon-based devices, the new device is easy to incorporate into medical and biological applications.
  • Unlike devices made from a single material (e.g., elastomer-only devices), the new device is capable of performing complex functions.
  • Unlike all other devices, the new self-regulating device functions autonomously without electronics or an external power source.
  • Unlike traditional microfabrication methods, this technology uses inexpensive methods to produce increased functionality.
  • Unlike devices that use expensive microchips in the channels, the new microfluidic device uses surface chemistry to expand its functionality.

In summary, the technology enables the economical, simple, and rapid fabrication of more functionally complex microfluidic devices than are available today.

Applications

  • Clinical medicine: Artificial lung, responsive drug (e.g., insulin) delivery, feedback control devices
  • Bioproduction: Protein production, assisted reproduction, filtration
  • Research: Incubation/maturation, infection, fertilization, chemical or other treatment of biological objects, reaction kinetics, high surface area sensing substrates, feedback control, drug candidate solubility
  • Bioanalysis: DNA analysis, sequence determination of proteins

Benefits

This technology dramatically expands the capabilities of microfluidic devices. It enables the economical, simple, and rapid fabrication of more functionally complex systems than are available today.

  • Simple: This technology greatly simplifies the fabrication process for microfluidic devices.
  • Less expensive: This technology uses less expensive materials and fabrication methods than those conventionally used to manufacture microfluidic devices.
  • Fast: This technology enables microfluidic devices to be constructed in minutes, as compared to days or weeks with more traditional fabrication methods.

Better devices: Microfluidic devices made using this technology have enhanced capabilities compared to those made with traditional fabrication methods:

  • Greater functionality
  • Autonomous operation; no external power supply or electronics are needed
  • Flexible design that is useful for medical and biological applications