Microfluidic Devices: Characterization Studies and Their Role in IVD Product Development
This article is the second in a two-part series on working with experienced third parties to design and integrate microfluidics into your IVD medical device. In the first article we discussed the value microfluidic technology brings to point-of-care development as well as the benefits of working with experts to streamline the incorporation of microfluidics.
An important benefit of microfluidic devices is that they enable several key processes—such as sample handling, cell sorting, and detection—to run on a single chip. Chips can then be integrated with off-chip devices, such as sample collection systems. Each of these processes an features must be designed with the manufacturing process in mind, especially if mass-scale manufacturing is a goal.
This is where characterization studies come in. Characterization studies are an important part of the microfluidic device design process. Characterization studies focus on the manufacturing process and parameters, and end-product functionality. In the end, these studies help ensure consistent microfluidic device quality and performance—and, ideally, more successful product commercialization.
Why Are Characterization Studies Important for Microfluidic Devices?
Characterization studies for microfluidic devices are performed with a number of goals in mind:
• To identify processes that impact product quality
• To identify ways in which processes affect quality attributes
• To ensure that the device is designed to be manufactured with reproducible quality and functionality
Ultimately, of course, a microfluidic device is intended to reach the end-user in a functional state. Characterization studies are a critical step to ensuring this. The studies identify ways in which the device can reach the end-user with consistent functionality and without delays or failed batches.
Know our expertise in microfluidic development
What Do Characterization Studies of Microfluidic Devices Entail?
When designing a microfluidic device, the goal is to meet the product’s requirements and design it to be easily manufacturable. During this phase, you should consider the optimal processes, materials, process parameters, and tolerances. Here’s a hypothetical characterization framework that might be used for incorporating a porous membrane into a consumable design:
1. What is the purpose of the membrane?
-Contamination control
-Ingress or egress
-Instrument interface
-Fluid flow control
2. Material Selection and Sourcing for Microfluidic Devices
-Pore size (ex. parameter: pressure drop across the membrane at define flow rates)
-Liquid present in test or not (ex. parameter: burst pressure of membrane material and liquid)
-Material compatibility (ex. parameter: cartridge polymer and membrane polymer)
-Material availability
(We have another piece on material selection for microfluidic devices, which you can read here.)
3. Bonding Process Selection for Microfluidic Devices
-Heat staking
-Ultrasonic welding
-Adhesives
-Laser welding
Many of these parameters come with a subset of their own highly-specific and impactful parameters and considerations. For example, parameters to consider for the heat staking manufacturing process include temperature, dwell time, pressure, flatness, and alignment. Each of these parameters are considered during the initial development of the microfluidic device to develop a workable manufacturing process. Following this, the parameters are expanded upon to provide a robust final product.
