Electrically Controlled Micro-Fluidic Device Pillar Electrowetting
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Capillary flow micro-fluidic devices are limited by unidirectional fluid movement and increased flow resistance, restricting their application to single-step bio-assays and reducing their ability to control fluid propagation precisely.
Innovation Solution
The introduction of electrically controlled capillary flow in micro-fluidic devices using pillars with individually adjustable voltage, allowing for modification of surface wetting properties to control fluid propagation, direction, and resistance through electrowetting, enabling precise control over fluid flow and the use of plasmonic nanoparticles for bioparticle detection.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Device complexity
If capillary action is used to drive fluid flow without external pumps, then device simplicity is improved, but fluid flow control precision deteriorates
Solution Approach 1:
The patent applies electrowetting to dynamically change the wettability of pillar surfaces in response to applied voltage, enabling real-time control of capillary flow. This dynamic adjustment allows the device to maintain simplicity while achieving precise fluid flow control by modulating surface properties rather than mechanical components.
Solution Approach 2:
The invention changes the electrical parameter (voltage applied to pillars) to control the wettability parameter of surface materials. By varying the applied voltage, the contact angle of fluid on pillar surfaces is modified, thereby controlling capillary pressure and fluid flow rate without adding mechanical complexity.
2Ease of operation
If pillars are individually connected to different electric power supplies, then fluid flow control precision is improved, but device complexity increases
Solution Approach 1:
The device segments the channel into multiple zones with independently controlled pillars, allowing localized fluid flow management. Each pillar or group of pillars can be addressed individually through separate power supply connections, enabling precise spatial control of capillary flow in different device regions.
Solution Approach 2:
The pillars serve multiple functions: they generate capillary action for fluid drive, act as electrodes for electrowetting control, and provide structural support. This multi-functionality reduces the need for separate control mechanisms, balancing the increased electrical control capability with acceptable device complexity.
3Ease of operation
If electrowetting is used to control surface charge, then fluid propagation control is improved, but energy consumption increases
Solution Approach 1:
The electrowetting control is applied periodically or in discrete steps rather than continuously, reducing overall energy consumption. Voltage is applied only when fluid propagation needs to be modified, allowing the system to consume energy selectively rather than continuously, while maintaining effective fluid propagation control.
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
This solution allows for dynamic control of fluid flow, overcoming resistance and enabling multi-step bio-assays, while the integration of plasmonic nanoparticles enhances bioparticle detection sensitivity and precision.
Implementation Method 1
The plurality of pillars being configured for creating a capillary action in the micro-fluidic channel when a fluid is present in the micro-fluidic channel
Implementation Method 2
The electrical control can be achieved via electrically modifying a surface charge of capillary micro-fluidic channels
Data Source
AI summary
An example micro-fluidic device includes a micro-fluidic channel having an inner surface and a plurality of pillars positioned along the inner surface. The device further includes a plurality of power supplies connected to the pillars. Another example micro-fluidic device includes a micro-fluidic channel having an inner surface and a plurality of pillars positioned along the inner surface. The device further includes a power supply. The pillars are grouped into at least two groups of pillars, each group of pillars including at least two pillars, and all pillars of at least one group of pillars are connected to the power supply. In another example, a sensing system for detecting bioparticles includes a micro-fluidic device, wherein a surface of each pillar comprises functionalized plasmonic nanoparticles or functionalized SERS nanoparticles, a radiation source for radiating the micro-fluidic device, and a detector for detecting SERS signals or surface plasmon resonance.