I need to measure the zeta potential of particles in various buffer. Before measurement we need to feed the values of dielectric constant, viscosity and refractive index of buffer. Please share if there are instruments to measure these properties.
Dear Prashant,
References -- Many real refractive indicies (589 nm) and viscosities for simple salt solutions are found in reference volumes such as the "CRC Handbook of Chemistry and Physics" or in Timmerman's book series (watch values and accuracy in this series) or Landolt-Bornstein's series. No doubt, less ancient texts exist with these values -- I'm just revealing my age by mentioning them to you :)
Experimentally -- real refractive indices by Abbe refractometer are quite simple to measure and U-tube type viscometers are fairly cheap to own, calibrate and operate. Include a glass pycnometer and a good water bath and you are on your way to 2 of the 3 things you want to measure.
Dielectric constants require construction of an apparatus or purchase of an existing apparatus. Perhaps if your buffer solutions are not covering too extreme a range of ionic strength you may be able to make some simple assumptions or extrapolations for these values? Then again, perhaps this forum has already answered this question for another ZP user. Did you search the forum for previous answers to similar questions?
Best regards,
Mike
For several common buffer components like salts, sugars, glycerol, ethanol, the Zetasizer software can calculate these parameters with the integrated solvent builder. It can be downloaded and used free of charge, without an instrument attached.
http://www.materials-talks.com/blog/2011/08/04/getting-ready-for-a-zetasizer-demo/
http://www.materials-talks.com/blog/2015/03/09/how-to-get-the-latest-software-for-the-zetasizer-nano/
Prashant Purwar
RI is easy to measure with an Abbe refractometer. See (registration required):
Uses of an Abbe refractometer
https://www.malvernpanalytical.com/en/learn/events-and-training/webinars/W120626AbbeRefractometer.html
Slide 19 provides a link to an Oxford University experiment on calculating dipole moment.
You can use Brookfield or Anton Paar viscometer to measure the viscosity. Many cheap refractometers are available for measuring the refractive index of milk. You will need a multimeter to measure the dielectric constant. Please see the article (DOI: https://doi.org/10.1515/9783110455403-007) for various ways to measure the dielectric constant.
- Badges
- Science topic
- Similar topics
- Geoscience
- Atmospheric Sciences
- Atmosphere
- Air