Viscosity & Viscometers

Are you measuring viscosity? If so, do you have preferred method or instrument to obtain decent values?

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I have measured viscosity and density for liquid class development. It was useful for gravimetric measurements of dispensed volumes and understanding why one liquid would behave differently than water.
I used the density viscosity meter combo from Anton Paar. I believe there is some limitation with sample recovery and incompatibility with certain reagents.

Interesting, I was also looking at another Anton Parr product as well.

Any specific reason for selecting that viscometer over their other offering?

Thanks by the way for the speedy response

Their customer rep was responsive and willing to work with me on my application. They let us use a demo instrument to confirm that it works for our purpose. We also ended up getting the IQ/IQ and a year PM from them.
They’re an established company and the rep for my area worked with mainly wine and beer so they were excited to work on a biotech application.
I don’t think I saw any other company with the same combo instrument because I think Anton Paar has the patent on their density meter.

Their other viscosity meters I believe are built for liquids/substances that don’t work with the one I linked. I believe the density model differentiators are the accuracy. How much are you willing to pay for an extra decimal.

All of my experience with the instrument was from 3 years ago, so some of it might have changed since then.

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Sounds good, I’ll reach out today.

Cheers

@EricSindelar_Hamilton I heard there was a way to measure viscosity with TADM. Is this true?

Yes, this is possible and we have developed a separate software application called ALP for Analysis of Liquid Properties. However, a patent prevents us from selling it stateside. I am not aware of it being further developed or supported due to this obstacle.

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I used the TADM curves a while back to estimate cell density which directly correlates with viscosity (although sadly non-newtonian…). I used an ANN that I trained on a dilution series and several measurements beforehand. That was quite straight-forward. It was surprisingly accurate and even surpassed my plate reader measurements for OD in wide range. So depending on your use case, that could be an option to avoid buying extra equipment and getting that measurement on the fly (I recorded 3 curves to average out any noise and automatically discarded the curve if I detected major outliers or spikes). There is a Bachelor Thesis somewhere sitting in my old uni hard-drive…

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Ah geez. :expressionless:

I’m in the process of potentially inheriting this viscometer and mulling over if it’s useful as part of an automation team’s toolkit. Does anyone else find value in having a viscometer on hand? https://new.marshallscientific.com/IKA-ROTAVISC-lo-vi-Complete-Viscometer-p/i-0025000310.htm?gad_source=1&gclid=CjwKCAjwrcKxBhBMEiwAIVF8rHiObVdpnzW3TKP8ZlJflo_TXFGRktEgI9zKGIVT5YahKXAL-55FzRoCJfsQAvD_BwE

Depends.

The Pressure Monitored Pipetting on a Tecan Fluent uses Artificial Intelligence (PMP-AI) to interpret pressure curves. Two inputs are required, density & viscosity of the liquid. You can then use a neural net to set up a set of interpretation criteria.

Using the neural net, your fine tuning for error cases and the system uses AI to adjust aspiration/dispense to accommodate a range of volumes and different tip types.

In theory, you don’t need to redo pressure curve validations every time. I love this because it potentially allows us to think about liquid classes in terms of the properties of the liquid and the mechanics of the hardware.

Just something to consider.