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Question

Posted on: March 6 2013

Gel for dental use becomes liquid.

Composition: Phosphoric acid 37%, sodium lauryl sulfate 0.1%, methylene blue 0.001% and Aqua AD 100%.
This compound gives a half liquid gel but I get a perfect result with 2 percent hypromellosum. But in function of time, the gel became liquid. Is this perhaps due to the influence of the acid?

Answer

I fear that we will have to test this out.
I would try with
  1. first hydroxyethylcellulose preferably a high viscosity
  2. or use CMC high Visceus
  3. or double the amount of HPMC