[scientizscht (OP)]

Hello

What is the maximum solubility of glucose oxidase in water?

I read various numbers like 0.2 or 5 mg per mL water but I wander if that is only it?

Also, are there any ways to increase solubility?

Thanks!

[Eternal Student]

I'm not an expert in BioChemistry,  this is just a general impression.

    Most substances vary their solubility according to the temperature of the water.  One issue for your molecule is that if the water gets too hot, that enzyme could denature.  Most of them do but I haven't studied that enzyme.  So you're probably only interested in a small range of temperatures.  The water will freeze at 0 C and stop being a good solvent, while at the other extreme the enzyme may denature at temperatures above its normal operating environment.  That enzyme is typically found in some fungi so it's normal operating temperature is likely to be less than 30 C.   You should check all these details yourself, I am offering "off the cuff" impressions only.

  If you don't care about the enzyme denaturing then you could heat the water as much as you like and the fragments of enzyme molecule left behind may be much more soluble in water.  You would have thoroughly destroyed the original molecule, so this may be considered cheating.

     Water is generally a better solvent for substances that have ionic and/or strongly polar regions.   Adding anything to the water that can bind with that enzyme and increase its polar character will usually increase its solubility.  This could be considered "cheating" since you aren't really examining the solubility of just that enzyme in pure water.  However, such things are done and the trick is to identify substances that will bind reversibly with the enzyme and not permanently denature it.

  Consider posting your question in the Chemistry section  or somewhere in the  Life Sciences section to attract opinions from Chemists and Biochemists.

[robertchannon1@gmail.com]

I have managed to get 25 mg/mL GOX dissolved in PBS through gentle stirring and no heating. I have been unable to find any literature or manufacturing information stating a water solubility limit. Good luck with your experiments,

Rob