Microfluidic Device with Shape Memory Polymer Fluid Actuation

Solution Overview

Problem

Conventional microfluidic devices require external driving means for fluid transport, which complicates assembly and is often incompatible with biochemical applications.

Innovation Solution

A microfluidic device with a shape memory substrate containing a thermally transformable shape memory polymer matrix and magnetically coercive particles that create a temporary vacuum by converting an alternate magnetic field into heat, allowing fluid flow without external driving means.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Ease of operation

If external driving means are used to transport fluid in conventional microfluidic devices, then fluid transport capability is achieved, but device complexity increases and compatibility with biochemical applications is compromised

Engineering Contradiction:

Improvefluid transport capabilityVSAvoidassembly complexity

Core Design Contradiction:

Ease of operationVSDevice complexity

Solution Approach 1:

The shape memory polymer substrate performs fluid pumping function autonomously through its shape transformation capability. When heated, the SMP substrate transforms from a first shape to a second shape, creating volume changes that generate pressure differences to drive fluid flow through the microfluidic channel without requiring external pumps or driving mechanisms.

Inventive Principle:

Principle #25Self-service

Solution Approach 2:

The patent replaces traditional mechanical external driving means (pumps, valves) with a thermal-mechanical actuation system. An external heat source triggers the shape memory polymer's phase transition, which mechanically drives fluid flow through the microfluidic device, eliminating the need for complex mechanical assembly while maintaining biochemical compatibility.

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

2Ease of operation

If external driving means are used for fluid transport, then fluid flow is achieved, but compatibility with biochemical applications is compromised

Engineering Contradiction:

Improvefluid transport capabilityVSAvoidbiochemical application compatibility

Core Design Contradiction:

Ease of operationVSAdaptability or versatility

Solution Approach 1:

The shape memory polymer substrate performs fluid pumping function autonomously through its shape transformation capability. When heated, the SMP substrate transforms from a first shape to a second shape, creating volume changes that generate pressure differences to drive fluid flow through the microfluidic channel without requiring external pumps or driving mechanisms.

Inventive Principle:

Principle #25Self-service

Solution Approach 2:

The patent replaces traditional mechanical external driving means (pumps, valves) with a thermal-mechanical actuation system. An external heat source triggers the shape memory polymer's phase transition, which mechanically drives fluid flow through the microfluidic device, eliminating the need for complex mechanical assembly while maintaining biochemical compatibility.

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

Applied Scientific Principles

This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.

Function Achieved in This Case

Enables self-sufficient fluid transport within the microfluidic device, simplifying assembly and ensuring compatibility with biochemical applications by inducing a temporary vacuum for fluid flow.

Implementation Method 1

the particles being made from a magnetically coercive material capable of converting energy of an alternate magnetic field into heat through magnetic hysteresis loss of the particles

Methodology Applied

Scientific EffectMagnetic hysteresis loss: Magnetic Hysteresis

Implementation Method 2

the shape memory polymer matrix being thermally transformable from a temporary shape to an original shape

Methodology Applied

Scientific EffectShape memory polymer thermal transformation: Shape Memory Polymer

Data Source

PatentUS8651451B2Microfluidic device with fluid driving capability

Publication Date: 2014.02.18 NATIONAL TSING HUA UNIVERSITY

AI summary

A microfluidic device includes: a shape memory substrate having a shape memory polymer matrix and a plurality of particles embedded in the shape memory polymer matrix, the shape memory polymer matrix being thermally transformable from a temporary shape to an original shape, the particles being made from a magnetically coercive material; and a microfluidic chip attached sealingly to the shape memory substrate and defining a microfluidic channel. The shape memory polymer matrix is indented inwardly to form an indented space in fluid communication with the microfluidic channel when the shape memory polymer matrix is heated to transform from the temporary shape to the original shape.