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Plasma Treatments

Plasma surface activation to improve adhesion

Plasma treatment of PDMS in microfluidic fabrication produces a permanent and irreversible bond between PDMS and glass, improving analyte flow within microfluidic channels.

PDMS (Polydimethylsiloxane) is by far the most popular material used in microfluidics research where it is deployed for rapid prototyping with minimal cost. PDMS, however, requires a surface treatment step in order to produce strong, conformal bonds between surfaces. Plasma treatment of PDMS increases hydophilic (-OH) groups on the PDMS surface which subsequently form strong covalent bonds (Si– O–Si) when brought together with glass. These covalent bonds form the basis of a practically inseparable seal between the layers.

Plasma treatment of PDMS for microfluidic applications - lab-on-a-chip

Plasma Treatment of PDMS

  • Removal of hydrocarbon groups
  • Exposure of hydrophilic -OH groups
  • Improved bonding to PDMS and glass substrates
  • Improve analyte flow
  • Possibility of patterned surfaces with alternating hydrophilic/hydrophobic regions

Plasma Treatment for lab-on-a-chip fabrication of microfluidic devices

An important group of devices is formed by bonding PDMS to patterned glass substrates. The following short video shows how simple it is to implement a reliable and repeatable PDMS bonding protocol using the Henniker HPT bench-top plasma systems.

Henniker Plasma systems can operate with both oxygen and air (and other gases). A typical PDMS bonding process would use oxygen ~ activation at low power for tens of seconds. The surfaces are brought into immediate contact for the best possible bonding results.

The Henniker HPT-100 and HPT-200 plasma surface treatment models are chosen for their ease of use and repeatability. They are simple to use bench-top instruments having digital mass flow controllers which allow both precise and repeatable plasma treatments whilst avoiding the common problems associated with manual needle valve gas inlets. This means the same conditions each and every time, a critically important point for reliable PDMS bonding.

The larger HPT-300 and HPT-500 instruments feature multiple tray-loading options and allow for increased capacity or treatment of larger devices. Each model of HPT plasma treatment system also features a continuously variable power level from 0-100% of full range so that power levels can be set precisely, both at low levels for activation of PDMS and at higher levels for effective cleaning and activation of glass.

Further details of PDMS-Glass bonding for microfluidics, along with articles explaining surface energy and how long plasma treatments last, can be found in the knowledge article links below.

A selection of recently published articles where the Henniker HPT systems are used for microfluidic research can be accessed from the following links:-

Related Industries

Relevant Resources

Knowledge Articles

See what our customers have to say

Vivid Dx Blue and transparent logo

"In 2024, we needed a plasma cleaner for rapid prototyping and PDMS microfluidic bonding. Henniker Plasma quickly identified the right system and provided practical PDMS bonding guidance. The system was delivered within 8 days, enabling us to start R&D earlier than planned. Same-day technical support and protocols have greatly accelerated our research."

Aaron Teo - Vivid Dx

Vivid Dx

"The technical team at Henniker are very knowledgeable and supportive and always approachable. I have found it a pleasure to work with them."

Simon Baxter - BAE Systems, MAI

BAE

"Henniker guided us to choose the most suitable plasma unit for our application, ensured an accelerated delivery time & guided us through the very easy setup. We obtained quality results with their unit within minutes of setup & consistent results thereafter. The support they have provided has been rapid and helpful."

Dr Ravi Desai - Making Lab, Francis Crick Institute

Francis Crick Institute

"Henniker provided our team with excellent service during the course of our work together, the plasma cleaner arrived quickly and was installed with ease, giving us visible results from the outset and confirming that we made the right decision in choosing a local UK manufacturer."

Dr Panagiotis Manesiotis BSc MRSC - Queen’s University Belfast

Queens Uni Belfast

"Our customers and operations demand reliability at every level and were a key factor in our decision to choose a UK based manufacturer of plasma treatment equipment."

Tom Doak - Trak Microwave

Queens Uni Belfast

"Henniker’s after sales support is first class. They have always been extremely responsive if we have ever had need to call on them."

Steve Rackham - Teledyne

Teledyne

"Henniker’s plasma systems have delivered tangible benefits to us right from day one. The team there are very easy to work with."

Ian Bruce - Coopervision

Coopervision

"Henniker really stood out, both in their product range and technical knowledge. They are a great company to work with."

Karthik Nair - University of Bradford

University of Bradford

"We are very impressed with the ease of use and reliability of our plasma unit and were producing results within minutes of setting it up."

Dr Neil Wilson - Warwick University

Warwick University

"Our collaborative work with the team at Henniker was a very positive experience and one that we look forward to developing further."

Ewen Kellar - TWI

TWI

"Henniker provided a tailored product to match our exact requirements. They are a pleasure to work with."

Dr Will Shu - Heriot Watt University

Heriot Watt University
Vivid Dx Blue and transparent logo

"In 2024, we needed a plasma cleaner for rapid prototyping and PDMS microfluidic bonding. Henniker Plasma quickly identified the right system and provided practical PDMS bonding guidance. The system was delivered within 8 days, enabling us to start R&D earlier than planned. Same-day technical support and protocols have greatly accelerated our research."

Aaron Teo - Vivid Dx

Vividdx

"The technical team at Henniker are very knowledgeable and supportive and always approachable. I have found it a pleasure to work with them."

Simon Baxter - BAE Systems, MAI

BAE

"Henniker guided us to choose the most suitable plasma unit for our application, ensured an accelerated delivery time & guided us through the very easy setup. We obtained quality results with their unit within minutes of setup & consistent results thereafter. The support they have provided has been rapid and helpful."

Dr Ravi Desai - Making Lab, Francis Crick Institute

Francis Crick Institute

"Henniker provided our team with excellent service during the course of our work together, the plasma cleaner arrived quickly and was installed with ease, giving us visible results from the outset and confirming that we made the right decision in choosing a local UK manufacturer."

Dr Panagiotis Manesiotis BSc MRSC - Queen’s University Belfast

Queens Uni Belfast

"Our customers and operations demand reliability at every level and were a key factor in our decision to choose a UK based manufacturer of plasma treatment equipment."

Tom Doak - Trak Microwave

Queens Uni Belfast

"Henniker’s after sales support is first class. They have always been extremely responsive if we have ever had need to call on them."

Steve Rackham - Teledyne

Teledyne

"Henniker’s plasma systems have delivered tangible benefits to us right from day one. The team there are very easy to work with."

Ian Bruce - Coopervision

Coopervision

"Henniker really stood out, both in their product range and technical knowledge. They are a great company to work with."

Karthik Nair - University of Bradford

University of Bradford

"We are very impressed with the ease of use and reliability of our plasma unit and were producing results within minutes of setting it up."

Dr Neil Wilson - Warwick University

Warwick University

"Our collaborative work with the team at Henniker was a very positive experience and one that we look forward to developing further."

Ewen Kellar - TWI

TWI

"Henniker provided a tailored product to match our exact requirements. They are a pleasure to work with."

Dr Will Shu - Heriot Watt University

Heriot Watt University