EURAMET 20NRM02 MFMET
Establishing metrology standards in microfluidic devices
Microfluidics, concerned with fluid-handling in the nano-to-millilitre scale, has major applications in biomedical and chemical analysis however global standards are lacking. ISO/TC48/WG3 has been set up to develop microfluidic standards covering metrology for the methodologies and fabrication processes that are essential to ensure measurement accuracy and traceability of devices. The goal of this project is to contribute to the development of globally accepted standards for microfluidics and disseminate them to end users in industry (health, pharmaceutical) and academia.
The increased technical capability required to miniaturise devices along with the growing need for faster, more accessible and cost-effective solutions for precision analytical tools has led to the rapid growth of microfluidics in diverse sectors (e.g. pharmaceutical and biomedical industries). However, due to this rapid growth, microfluidics and specifically the control of fluids in microfluidic devices still lacks universal solutions and standards. Stakeholders from industry, academia and government have recognised these needs  and as a result ISO/TC48/WG3 has been set up to develop microfluidic standards covering metrology for the methodologies and fabrication processes that are essential to ensure measurement accuracy and traceability of devices.
Standardisation of performance characteristics is needed for the different classes of components, including test conditions, measurement protocols and guidelines. The increasing demand for passive flow devices has already led NMIs to establish protocols and calibrations services for the small flow rates [2,3]. Traceability to National Standards has been available since 2012 down to 0.1 μL/min through facilities developed under EMRP JRP HLT07 MeDD. Also, in 2018 a new EMPIR JRP 18HLT08 MeDDII, related to microflow measurements down to 5 nL/min, was set up and the new facilities are now under implementation. This new technology can now be used to develop microfluidic measurement protocols, and the new microflow pump devised in MeDDII can be used as a traceable flow generator.
In 2016, a first step towards microfluidic standardisation was made through ISO IWA23 . The document was created to facilitate the uptake of microfluidic devices by making them easier to use, reducing the cost for assembling and enabling plug and play functionality. Recently a new standard, ISO/CD 22916 , is being established based on the information from ISO IWA 23 and it will replace this document; however, this new standard still lacks the metrological specifications required for accurate and reproducible manufacturing.
 D.R. Reyes and H. Van Heeren, Proceedings of the First Workshop on Standards for Microfluidics, Journal of Research of the National Institute of Standards and Technology, Volume 124, Article No. 124001 (2019). https://doi.org/10.6028/jres.124.001
 Metrology for Drug Delivery, EURAMET EMRP JRP HLT07, www.drugmetrology.com
 E. Batista, A. Furtado, J. Pereira M. Ferreira, H. Bissig , E. Graham , A. Niemann , A. Timmerman, J. Alves e Sousa , F. Ogheard , A. W. Boudaoud, New EMPIR project – Metrology for Drug Delivery, Flow Measurement and Instrumentation, Volume 72, April 2020, 101716. https://doi.org/10.1016/j.flowmeasinst.2020.101716
 ISO IWA 23:2016 – Interoperability of microfluidic devices – Guidelines for pitch spacing dimensions and initial device classification. https://www.iso.org/standard/70603.html
 ISO / CD 22916 – Laboratory equipment — Interoperability of microfluidic devices. https://www.iso.org/standard/74157.html
The overall objective of this project is to contribute to the development of globally accepted standards for microfluidic devices used particularly in the health and pharmaceutical industry.
The specific objectives are:
1. To investigate, evaluate and formulate consensus-based flow control specifications, guidelines and protocols to enhance the manufacturing capability of the microfluidics industry supply chain through voluntary compliance.
2. To develop measurement protocols for different flow quantities and liquid properties, in different microfluidics devices to be used in pharmaceuticals, biomedical and mechanobiology applications. A EURAMET guide and a technical report on these measurement protocols will be developed.
3. To define consensus-based standards and guidelines for interfaces and connectivity between fluidic passages and optical/electrical connections of microfluidics components and corresponding measurement standards, from micro to macro size scales.
4. To define guidelines for the standardisation of dimensions and accuracy for modularity (either module-to-module or module-to-world) and sensor integration (combination of sensing elements/materials with microfluidic modules), in accordance with good practices in microfluidic component design and manufacturing.
5. To collaborate with ISO/TC48/WG3 and end users of the standards (e.g. health and pharmaceutical industry) to ensure that the outputs of the project are aligned with their needs and in a form that can be incorporated into standards (e.g. new technical guides, ISO 10991 and ISO/CD 22916) at the earliest opportunity