PHD Defense - Abir Boudaoud - 16/12/2022 - Development of a Primary System for the Measurement of Nano-flow Rates of Liquids

Abir Boudaoud’s PhD Defense will take place on:
December 16th at 2pm
IPGG amphitheater
6 Rue Jean Calvin, 75005 Paris

Development of a Primary System for the Measurement of Nano-flow Rates of Liquids

Abstract:

The metrological traceability of liquid flow rate measurements is
ensured by an uninterrupted chain of calibrations against national
primary and transfer standards. However, for flow rates that fall
below a few microliters per minute, traceability becomes difficult due
to the lack of references at this scale. In this work, and as part of
the «Metrology for Drug Delivery II» European joint research project,
we developed a primary system for the measurement of low liquid flow
rates based on the optical tracking of a liquid/air interface moving
inside a glass capillary tube. A quantification of the physical
phenomena occurring at the interface and an assessment of the
different uncertainty components were carried out. In
order to ensure the traceability of flow rate measurements, a camera
calibration procedure has been established and a method for measuring
the inner diameter of capillary tubes has been developed. The system
allows the calibration of liquid flow generating and measurement
devices such as drug delivery systems, flow sensors, pressure
controllers and syringe pumps. These devices are used for e.g. medical
and microfluidics applications. Our system also enables the study of
flow rate fluctuations and thus, a complete characterization of flow
generating devices. As part of the external validation of the system,
CETIAT participated in an interlaboratory comparison which consists in
the calibration of different flow meters and a flow generator, from 5
nL/min to 1500 nL/min, for both static and dynamic flows. The results
of the comparison show a measurement-expanded relative uncertainty
ranging from 12 % at 10 nL/min to 0.15 % at 1500 nL/min. These
measurement and calibration capabilities (CMCs) were peer-reviewed and
validated by BIPM’s (International Bureau of Weights and Measures)
approval process. This validation represents international recognition
of our system as the French national primary standard for liquid
nano-flow rates.