
Optical microfluidic bubble detector
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Optical microfluidic bubble detector
Elveflow provides a unique microfluidic bubble detector. It can identify if liquid is present in clear tubes. It can be plugged directly onto our OB1 flow controller, or it can be used as a standalone unit with the Sensor Reader and another instrument.
The sensor is able to register the presence of fluids inside clear tubing, trigger a signal to another instrument and act accordingly – like stop, wait a certain amount of time, allow enough flow to clear the tubing, or reset the sensor.
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The microfluidic bubble detector comes in two different housings suited to the use with 1/16″ or 1/4″ outside diameter tubes.
Advantages :
Applications
One particular application worth to mention is using the sensor as a microfluidic bubble detector. Bubbles are a big challenge to address in microfluidics, as they can induce flow modifications or interact with the experiment and cause damages to the sample. One can monitor the apparition of microfluidic bubbles (change of the working fluid) at any given point of his setup and automate the experiment accordingly like, increase the pressure, switching valves to direct the bubble in another fluidic path for instance. For further information check out the example tab on this same page.
The microfluidic bubble detector detection is based on the measurement of the optical path and the variation of this path when the medium flowing is changing.
A light beam is emitted by a LED at known power. This light beam goes through the capillary and the fluid passing through. It is then collected by an NPN silicon phototransistor. This phototransistor converts the light power into an electrical power.
When a fluid changes, the optical index and the light absorption coefficient change accordingly. It induces a change in the electrical power and allows to detect changes in the fluid.

Dedicated software module

Thanks to an intuitive module, the Elveflow® Smart Interface allows to take out the best of the microfluidic bubble detector instruments from the simplest commands for beginners to the most complex manipulations for experts… More information about the module.
Control your experiments through C, Python, Matlab®, Labview® or the Elveflow® Smart Interface. The Elveflow® Smart Interface is a software application offering all the functionalities that experimentalists need. Get a glimpse of what’s doable here!
The microfluidic liquid sensor has many applications. This is one is a smart way to perform bidirectional recirculation without using valves.