Once you get casein into solution with TBST as the solvent, does it come out of solution if stored for 5-7 days at 4 degrees Celsius?
If it does, is there a way to keep it in solution for that amount of time?
Respected Utsw Employee
To ensure that casein remains in solution during storage, it's essential to maintain proper conditions and prevent factors that could lead to precipitation. When using TBST as the solvent, thoroughly dissolving casein and gentle mixing can help prevent its settling. Storing the solution at 4 degrees Celsius also slows molecular movement, reducing the likelihood of casein coming out of the solution. However, over time, precipitation may occur despite these precautions. To minimize this risk, periodic gentle agitation or stirring of the solution during storage can help redistribute any settling particles and maintain homogeneity. Additionally, adding stabilizing agents such as protease inhibitors or glycerol to the solution may help prevent precipitation and maintain the stability of the casein solution over extended storage periods.
How often would you suggest stirring the solution in storage?
Also, how long would you be able to store the solution at room temperature if it were on a nutator?
To ensure casein stays in solution during storage, it's important to manage several key factors related to the stability of the solution:
1. **pH Control**: Casein is most stable in a slightly alkaline or neutral pH range (around pH 6.6 to 7.5). Ensure that the solution is buffered to maintain this pH range. Using buffers such as phosphate or bicarbonate can help maintain the pH and prevent precipitation.
2. **Temperature**: Store the solution at a consistent, cool temperature. Room temperature is usually sufficient, but for longer storage times, refrigeration (around 4°C) can help maintain stability.
3. **Avoid Agitation**: Minimize shaking or vigorous stirring, as mechanical stress can lead to denaturation and precipitation of casein.
4. **Sterility**: Ensure the solution is sterile to prevent microbial growth, which can alter pH and lead to precipitation. Sterile filtration or autoclaving (if the solution composition allows) can help maintain sterility.
5. **Concentration**: Keep the concentration of casein within a range that it remains soluble. Highly concentrated solutions are more prone to precipitation.
6. **Additives**: Adding stabilizers or co-solvents like glycerol or ethanol in small amounts can sometimes help maintain solubility. However, this depends on the specific application and compatibility with other components in the solution.
7. **Regular Mixing**: If the solution is stored for an extended period, gentle mixing or stirring periodically can help maintain homogeneity without causing denaturation.
By carefully managing these factors, you can help ensure that casein remains in solution during storage.