Flow Control

Flow control is a key function of a complex microfluidic lab-on-a-chip. It is essential to manage all the different on-chip testing steps, in the right way and at the right time. On-chip flow control enables the design of a compact and autonomous microfluidic platform, which is essential in the growing market for instant medical applications. Alfa Chemistry provides a variety of solutions for the flow control function of the lab-on-a-chip.

You can achieve the following steps through our micro-flow control service:

• Accurate volume sampling
• Mixing of a specific volume
• Multiple washing steps
• Incubation and heating
• Time and space control of the fluid flow

Please tell us your application-specific needs, and we will provide the design according to your requirements.

About Our Flow Control Service

• Types of flow control

We offer two types of flow control: active flow control and capillary flow control.

• 

  Active Flow Control

  Active flow control relies on external input to drive, and belongs to a mechanically driven type of microfluidic flow control that provides dynamic flow drive.

  The active flow control system provided by Alfa Chemistry is based on a fully integrated diaphragm valve and pump, which are actuated by a pneumatic control system. We use obviously transparent materials and provide reliable on-chip valves and pump systems in a variety of materials and hybrid combinations. For more information on the various materials we use, see Underlying materials.

• 

  Capillary Flow Control

  Capillary-driven microfluidic flow control determines the driving of flow through the complex characteristics of the microfluidic channel structure itself, such as the geometry of the channel and the surface characteristics of the channel. In order to meet customers' specific requirements, we can:

  • Adjust the channel surface to achieve the required flow conduction and ensure capillary filling.
  • Adjust the geometry of the channel to control the flow and make the flow stop and start at the right point and at the right time.

• Microfluidic device

The capillary burst valves we provide can be used to adjust the flow in the capillary drive system. The working principle of these valves relies on a sudden increase in the cross-section of the microfluidic channel, which causes the capillary filling to stop at the transition. When a different fluid flow passes through the connection point, the flow will restart.

• Electrostatic triggering

Alfa Chemistry can induce the influence of time components on multi-step analysis by electrostatic triggering. When the flow stops at the capillary burst valve, the application of a short voltage will re-trigger the flow. The principle of operation is to apply a voltage between two electrodes located before and after the valve. Applying a voltage draws the meniscus to the second electrode and triggers the valve.

• Microfluidic hybrids

Alfa Chemistry focuses on the development of polymer substrate technology and is able to integrate functional components, capillary valves and metal electrodes into polymer-based microfluidic chips. We can provide you with the following:

• All glass equipment
• Glass equipment with PDMS membrane
• COC device with elastic COC film
• Polystyrene/SEBS film

Our products and services are for research use only.