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Updated: Aug 2, 2026
10:56
Confocal Imaging of Confined Quiescent and Flowing Colloid-polymer Mixtures
Published on: May 20, 2014
Reply to "Comment on 'Monte carlo study of structural ordering in charged colloids using a long-range attractive
1Materials Science Division, Indira Gandhi Centre for Atomic Research, Kalpakkam 603 102, Tamil Nadu, India.
Summary
This study refutes claims that colloidal particle measurements invalidate Sogami-Ise theory. Conductivity and conductometric titration measurements suggest Grier and Crocker
Area of Science:
- Colloid science
- Physical chemistry
- Surface science
Background:
- Grier and Crocker's work claims to invalidate Sogami-Ise (SI) theory using colloidal particle suspension data.
- Their findings suggest Dejaguin, Landau, Vervey, and Overbeek (DLVO) theory is applicable.
- This work critiques their experimental data and interpretation.
Purpose of the Study:
- To refute the claims made by Grier and Crocker regarding SI theory.
- To present evidence supporting the continued validity of SI theory.
- To address the interpretation of colloidal interactions under confinement.
Main Methods:
- Re-analysis of experimental data presented by Grier and Crocker.
- Conductivity measurements to estimate effective charge of colloidal particles.
- Conductometric titration to determine the number and nature of dissociable sites.
Main Results:
- The experimental data presented by Grier and Crocker, using not well-characterized samples, do not provide clear evidence for the failure of SI theory.
- Conductivity and conductometric titration measurements offer alternative interpretations of colloidal interactions.
- The effect of charged wall confinement on measured colloidal interactions is re-evaluated.
Conclusions:
- The criticism of SI theory by Grier and Crocker is unfounded based on the available evidence.
- Further rigorous experimental validation is required to challenge established theories like SI theory.
- The interpretation of colloidal particle behavior requires careful consideration of sample characterization and measurement techniques.
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