Recommend the best alkaline metal-based desiccant for a storing an extremely hygroscopic protein

So you mean alkali metal or alkaline earth metal? The way you have it written (half and half) I can't tell. My choice for desiccants is Mg(ClO4)2. CaCl2 is cheaper but I think Mg(ClO4)2 is better.

Actually the entire question I needed help was :

Recommend the best alkaline metal-based desiccant for a storing an extremely hygroscopic protein. Give your reasons. NB Desiccants are drying agents and usually kept physically separated from perishable materials

I don't know that much about biochemistry. My best guess is that proteins require special care that the desiccant is not TOO good. Try your text. I didn't see anything on the web.

When it comes to choosing a desiccant for storing an extremely hygroscopic protein, alkaline metals are generally not used due to their high reactivity. Alkaline metals, such as lithium, sodium, and potassium, have a tendency to undergo chemical reactions with moisture and can cause degradation or even react violently.

Instead, the commonly used desiccants for protein storage are silica gel and molecular sieves. Silica gel is a highly effective desiccant that can absorb moisture up to 40% of its weight, whereas molecular sieves are synthetic porous materials with even higher moisture-absorbing capacities.

To determine the best desiccant for your specific protein, you should consider the following factors:

1. Compatibility: Ensure the desiccant does not react or interfere with the protein's stability, structure, or function. Silica gel and molecular sieves are generally inert and non-reactive towards proteins.

2. Moisture adsorption capacity: Check the moisture adsorption capacity of the desiccant. Molecular sieves tend to have higher adsorption capacities compared to silica gel.

3. Particle size: Choose a desiccant with an appropriate particle size to avoid any physical interactions or damage to the protein. Smaller particle sizes are generally preferred to minimize any potential contact.

4. Packaging: Proper packaging is crucial to maintain an airtight environment. Use a material that is impermeable to moisture and ensure the desiccant is properly sealed within the storage container.

Remember, it is always recommended to consult with protein storage experts or follow established protein storage guidelines for your specific protein to ensure optimal conditions and prevent any potential degradation.