PMMA Microfluidic Chips
Custom PMMA microfluidic designs reviewed for manufacturability before you place an order.
What Is PMMA Microfluidics?
PMMA — poly(methyl methacrylate), also known as acrylic — is among the established thermoplastics in research microfluidics. It is optically clear, dimensionally stable, and can be machined and bonded into closed channel structures without the tooling investment that injection moulding requires.
For teams that want to work directly in a rigid thermoplastic during development, PMMA provides a route from machined prototypes toward thermoplastic replication processes without requiring dedicated mould tooling at the earliest stage. Material selection should still follow the application.
Why PMMA for Rapid Prototyping
Optical clarity
PMMA transmits visible light well, which matters where you need to observe flow, detect a colour change, or image through the chip.
Specific transmission figures and grade designations are not published here. Optical requirements for your project should be stated in your RFQ so they can be reviewed against available material.
Machinability
PMMA can be micromachined without dedicated mould tooling, which makes it useful for iterative thermoplastic prototyping. Actual surface quality, feature capability, setup cost and unit cost depend on the stock material, geometry, tooling and manufacturing route.
Cost during early iterations
Avoiding dedicated mould tooling can reduce the upfront commitment during early design iterations. Whether machining remains economical at higher quantities is project-specific.
What to Tell Us About Your Operating Conditions
Material suitability is grade- and condition-dependent. Rather than publishing general limits, we ask for the conditions the part will actually see.
Chemical compatibility
If your protocol involves organic solvents, cleaning agents or extended reagent exposure, provide the exact chemical, concentration and exposure condition. Compatibility is grade- and condition-dependent.
Temperature exposure
State operating temperature, sterilisation method and any thermal cycle. Suitability should be reviewed against the selected PMMA grade and bonding route.
Optical wavelength
If wavelength-specific transmission matters, specify the wavelength range rather than assuming generic optical clarity is sufficient.
Grade-specific chemical compatibility, thermal limits and transmission values are not published here. They are reviewed against the conditions you supply and the material grade available for the project.
Providing these conditions in the RFQ allows material suitability to be reviewed before quotation rather than assumed.
Design Considerations
These are aspects of a microfluidic design that bear on whether a part can be made as drawn — and that are worth considering before you send a file.
Channel geometry and aspect ratio
The relationship between channel width and depth affects how a feature can be machined. Narrow, deep channels are more demanding to produce than shallow wide ones, and there is a practical limit to how deep a given width can go.
Minimum achievable channel width, minimum depth and maximum practical aspect ratio depend on the manufacturing route and are confirmed during manufacturability review. No general figures are published here.
Internal corners
An internal corner in a machined channel cannot be sharper than the tool that produced it. If your design assumes a square internal corner, the produced part will have a radius there. Where corner geometry matters to your fluidics — for example at a junction — state it explicitly in the drawing rather than leaving it implied.
Chambers and reservoirs
Larger open volumes behave differently from channels: they may need consideration for how they fill, how bubbles escape, and how the cover layer behaves across an unsupported span. A wide, shallow chamber with a thin cover can deflect.
Ports and external interfaces
Ports and external interfaces deserve particular attention because sealing and alignment requirements are often different from the fluidic geometry itself.
Worth specifying:
- Whether ports are threaded, straight, counterbored, or intended for a specific commercial fitting
- Which fitting standard, if any, the design targets
- Whether tubing is inserted into the port or connected via a fitting
- Whether the port face requires a particular finish for sealing
An under-specified interface can produce a part whose internal geometry is acceptable but whose connection to tubing or a manifold is unreliable.
How bonding affects final geometry
The channel in your CAD file is the channel before the cover is attached.
Bonding processes can alter channel geometry. Depending on the bonding route, the finished channel cross-section can differ from the drawn one — a channel may end up slightly shallower, its corners slightly rounded, or its cross-section slightly changed near the bond interface.
Whether this change matters depends on the function of the device and the magnitude of the geometry change. If final channel cross-section is function-critical, identify it before the bonding route and inspection plan are agreed.
Typical R&D Applications
PMMA prototype chips are used for applications including droplet generation and manipulation studies, mixing and gradient generators, cell culture and perfusion devices, sample preparation structures, flow-cell components inside larger instruments, and fluidic concept validation before committing to a moulded design.
Preparing Your Design for Review
A useful RFQ package contains:
- A 3D file — STEP or STP for the geometry
- A 2D drawing — PDF or DXF showing which dimensions matter and what tolerance applies to them
- A short statement of intent — what the chip does, and which features are functionally critical
A short statement of intent gives the reviewer information that the geometry alone does not contain: which features carry the function and which requirements have flexibility.