Hi, I guess you mean the artificial sputum medium (ASM), am I right?

If I am right, the ASM has been developed since 2005 by Sriramulu.

the main components are Mucin, amino acids, DNA, egg yolk emulsion, and electrolytes.

Here is the link https://www.nature.com/protocolexchange/protocols/1999Accessed#/author-information

However, since then many research teams have been trying to develop and modify Sriramulu's protocol to obtain their specific desired solutions, regarding to the percentage of mucin and DNA, and other modifications.

You can see the publish papers of these researchers. They are good ones.

Sebastian Kirchner

William J. Comstock

I am studying and trying to develop the ASM as well.

Thanks for your response Pongsiri.

Yes I had referred to the ASM protocol earlier, this is

chemically the same as sputum but lacks the viscosity of it.

but I was looking at something which can replicate the viscosity of sputum too.

Are you looking at developing something like ASM which can match the viscosity of sputum?

The percentages of mucin range from 0.5 - 5% depending on the authors. The original one was 0.5%, but some studies suggested to increase the concentration to 2% to reflect the real viscosity of sputum.

However, I understand your point that the ASM does not reflect sputum viscosity. Since I prepare 5% mucin for my stock solution and the final concentration of mucin was 2%, both of them are very watery.