Fluid Handling Device Channel Contact Angle Optimization
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing methods for generating liquid droplets for high-precision analysis, such as in clinical and environmental tests, face issues where high-affinity samples adhere to channel walls, leading to incomplete division and laminar flow, especially with high-viscosity samples.
Innovation Solution
A fluid handling device with a configuration that includes a sample channel, a dispersion medium channel, and a dispersion liquid channel, where the contact angle between the inner wall of the dispersion liquid channel and water satisfies the equation Y≤0.0436X−1.2563, ensuring that liquid droplets do not adhere to the channel walls, and a method involving a polar solvent sample and a non-polar solvent dispersion medium to effectively disperse the sample.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If the affinity between the channel material and the sample is high, then the sample can be effectively transported through the channel, but the divided liquid droplets adhere to the wall surface of the channels, preventing appropriate division and making it difficult to generate a dispersion liquid
Solution Approach 1:
The invention changes the surface property parameter of the channel by controlling the contact angle between the inner wall and water to be 90° or more. This parameter change reduces the affinity between the channel wall and the aqueous sample, preventing adhesion while maintaining effective transport. The specific relationship Y≤0.0436X−1.2563 between contact angle X and sample viscosity Y quantifies this parameter optimization.
Solution Approach 2:
The invention introduces the contact angle as an intermediary parameter that mediates between the channel material and the sample. By adjusting the contact angle to 90° or more, the channel wall acts as a neutral or repelling intermediary rather than an attracting surface, preventing direct adhesion between the sample and channel wall while allowing continuous phase to effectively divide the sample into droplets.
2Ease of operation
If the viscosity of the sample is high, then the sample may be easier to handle, but liquid droplets adhere to the wall surface of the channels and become laminar flow, preventing appropriate division
Solution Approach 1:
The invention establishes a quantitative relationship between contact angle X and sample viscosity Y (Y≤0.0436X−1.2563) to optimize handling of viscous samples. By setting the contact angle to 90° or more, the channel surface becomes sufficiently repelling to counteract the adhesion tendency of high-viscosity samples, enabling effective droplet division while maintaining ease of operation.
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
The solution reliably generates dispersion liquids with dispersed liquid droplets, preventing adhesion and ensuring smooth flow, even with high-viscosity samples, thereby facilitating accurate analysis.
Implementation Method 1
a sample or the like is introduced, from a second channel connected to a first channel, into a continuous phase (dispersion medium) flowing through the first channel in a microchannel, and the sample is divided into liquid droplets by a shearing force of the continuous phase
Implementation Method 2
Y≤0.0436X−1.2563 is satisfied, where X denotes a contact angle [°] between a portion of an inner wall of the dispersion liquid channel and water
Data Source
AI summary
An objective is to provide a fluid handling device capable of reliably generating a dispersion liquid in which a liquid droplet containing a sample is dispersed in a dispersion medium. The fluid handling device achieving the objective includes: a sample channel; a dispersion medium channel; a dispersion liquid generation part connected to the sample channel and the dispersion medium channel, and configured to divide the sample by the dispersion medium to generate a dispersion liquid in which a liquid droplet of the sample is dispersed in the dispersion medium; and a dispersion liquid channel connected to the dispersion liquid generation part, in which Y≤0.0436X−1.2563 is satisfied, where X denotes a contact angle [°] between a portion of an inner wall of the dispersion liquid channel and water, and Y denotes a viscosity [mPa·s] of the sample measured at 25° C. by a falling-ball viscometer.