Hi Ya'All, You might want to save or print this.
Ions vs particles in CS If you have not printed Stuart's post Wed. 09 May 2000 12:33:30-0700 Biologic Transport of Silver Ions you should, as it definitely answers the question that Ionic silver is a must. PPM measurements When I acquired my spectrophotometer for measuring PPM of Cs it was of no value until it was calibrated against a National Bureau of Standards solution of Silver nitrate in 5% HNO3 solution. I have since correlated with James H. and Dr Bruce Marx. both have spectrophotometers. I have also correlated with Stephen Quinto's AA and Kimball Labs. AA. So I know that my readings are correct. Particle Size measurements The CS used in AA measurements the T.E.M., and Zetasizer were of the same lot. The T.E.M. provides a photograph of the silver material in the solution. Like all measuring equipment it must be calibrated against any known particle standard. The Zetasizer provides and electrical output of an optical scanning of the solution and generates a graphical response. Likewise this instrument must be calibrated preferably against an ionic silver standard, otherwise the "X" axis can be shifted to any position. If both machines were properly calibrated then the T.E.M. and the Zeta plot should be almost identical and not off by a factor of 20, as is in the measurement of my CS. I asked Malvern of Arkansas if there equipment could measure ionic sliver in the 1 to 8 nm range and the answer I received was, "several companies in the world are using it for that." Think about that answer. It is not a direct answer to my question. I also would like to know what silver ionic standard was used to calibrated the Zetasizer. This may sound trite but the accuracy of measurements is the key to understanding what we are doing. "Ole Bob:
