Short answer:Silicone sealing on microfluidic chips must isolate adjacent microchannels using very low clamping force, while ensuring that the silicone does not squeeze into the channels and alter the flow resistance. The dimensions, flatness, material purity, and assembly load of the micro-sealing ribs must all be precisely controlled.
In what kinds of situations are these silicone parts suitable?
Clearly defining the actual application scenarios helps translate material, structural, and validation requirements into actionable technical specifications.
- Diagnostic chips, analysis cartridges, and reagent flow paths
- Micro Pump, Valve, and Sensor Interfaces
- Multi-Channel Liquid Dispensing and Gas Line Control
Parameters to Confirm Before Selecting a Model
We recommend providing the following information before requesting a quote or ordering a sample to minimize the need for repeated prototyping and misunderstandings regarding specifications.
- Channel width and depth, voltage, and allowable series leakage
- Chip Materials, Flatness, and Assembly Methods
- Reagent Compatibility, Cleanliness, and Biological Requirements
Key Points in Structural Design
Structural dimensions, assembly relationships, and material elasticity must be evaluated together; simply increasing a single parameter generally does not directly improve reliability.
- Micro-sealing ribs bypass the channel and maintain continuity
- A limiting structure prevents overpressure from entering the flow channel
- Alignment of Positioning Features Between the Control Chip and the Spacer
Production and Quality Control
Consistency in mass production results from the combined control of material batches, mold condition, molding windows, and inspection methods.
- Precision molding is used to control microstructure dimensions
- A clean environment reduces particulate and surface contamination
- Microscopic examination revealed gaps in the resin, rough edges, and localized depressions.
Recommended Verification Items
Validation should be conducted using actual or equivalent operating conditions whenever possible, and functionality should be reconfirmed after aging or cycling.
- Conduct channel hold-pressure and cross-leakage tests separately
- Measure the flow rate and pressure loss before and after assembly
- Warming, Storage, and Retesting After Media Handling
Frequently Asked Questions
Does applying more pressure prevent leakage?
Excessive pressure may clog the passageway and alter the flow rate.
Can standard flat gaskets be used in microfluidics?
This typically requires a specialized micro-sealing rib and positioning design.
How do I provide information to suppliers?
Please provide 2D or 3D drawings, photos of samples, material and hardness specifications, operating environment, target quantity, acceptance criteria, and a list of compliance documents. Based on this information, Chengxin Silicone Rubber can evaluate the materials, molds, molding process, and validation plan.