Sol-Gel Microfluidic Device Production via High Condensation Ratio
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional methods for manufacturing microfluidic devices in silica glass are expensive, time-consuming, and limited in patterning performance, especially for micron and milli-scale structures, and require hazardous chemistry, making them unsuitable for high-pressure and organic solvent applications.
Innovation Solution
A sol-gel method using a sol with a high condensation ratio, prepared from alkoxysilanes, is employed for patterning and sealing microfluidic devices, allowing for the creation of microchannels with depths ranging from 1 μm to 1 mm, using flexible stamps and organic solvents to achieve stable and transparent hybrid silica glass devices.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If conventional etching technologies are used for glass patterning, then microfluidic devices can be manufactured, but the process becomes expensive, time-consuming, and offers limited patterning performance
Solution Approach 1:
The patent changes the chemical parameters of the sol-gel process by using a high condensation ratio sol (≥75%) with specific water content (5-20 wt%) and organic solvent composition. This parameter optimization enables the sol to maintain stability during imprinting while achieving complete curing, thus improving patterning performance and reducing manufacturing time compared to conventional etching methods
Solution Approach 2:
The patent replaces the mechanical/chemical etching process with a sol-gel chemical deposition process. Instead of removing material through etching, the method deposits a cured sol-gel layer that is then imprinted, achieving superior patterning performance while significantly reducing process time and complexity
2Manufacturing precision
If silicon-alkoxides sol-gel methods are used, then nanofluidic devices can be produced, but the method is incompatible with micro and milli-scale structures due to large solvent content
Solution Approach 1:
The patent optimizes the sol composition parameters by controlling the water content (5-20 wt%), organic solvent type and amount, and condensation ratio (≥75%). These parameter changes reduce the solvent content and increase the solid content, making the sol suitable for both nano- and micro-scale imprinting while maintaining ease of manufacture through simple mixing and curing steps
Solution Approach 2:
The patent creates a composite sol system combining inorganic alkoxysilane precursors with organic solvents and catalysts. This composite formulation allows the sol to exhibit both the reactivity needed for nanoscale precision and the reduced viscosity required for microscale imprinting, achieving universal applicability across different length scales
3Manufacturing precision
If high condensation ratio sol is used, then microfluidic devices with controlled dimensions can be produced, but shrinkage during curing must be minimized
Solution Approach 1:
The patent carefully balances the condensation ratio (≥75%) with water content (5-20 wt%) and organic solvent composition to achieve optimal crosslinking density. This parameter optimization ensures sufficient dimensional control during curing while limiting excessive shrinkage that would distort microchannel geometry, maintaining both precision and shape fidelity
Solution Approach 2:
The patent applies different functional requirements to different regions of the sol-gel system: the crosslinking network provides dimensional stability and control in the bulk, while the organic solvent content maintains lower viscosity and reduced shrinkage at the molecular level. This local quality differentiation resolves the contradiction between dimension control and shrinkage
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 method enables the rapid, cost-effective production of transparent, high-pressure-resistant microfluidic devices with controlled microchannel dimensions, suitable for various applications including oil recovery and biological studies, while minimizing shrinkage and maintaining surface properties.
Implementation Method 1
hydrolysis of at least one alkoxysilane of formula (I) RnSi(OR′)4−n using at least one aqueous solution of at least one water soluble organic acid catalyst
Implementation Method 2
condensation of the so-obtained hydrolysate
Data Source
AI summary
The present invention relates to a method for producing a microfluidic device, in particular, a sol-gel method for producing a microfluidic device in hybrid silica glass. The invention also relates to a microfluidic device obtainable by the method as described above and to microfluidic device in hybrid silica glass comprising at least one microchannel having a depth of at least 1 μm, preferably between 1 μm and 1 mm, and more preferably between 10 and 100 μm.