Hi,
I am wondering if synthetic human islet amyloid polypeptide (IAPP) can be prepared just like beta-amyloid using NH4OH instead of using HFIP.
Concerns:
1- I am not allowed to use Lyophilizer using organic solvents.
2- It will be too risky to have a trial on a pre-packed IAPP powder (1 mg) as per their cost is concerned.
I would truly appreciate if somebody will let me know if they succeeded in preparing IAPP with a similar aggregation behavior as prepared in HFIP.
Thanks in advance.
Best regards,
Bikash
The pI of amyloid beta is 5. Human IAPP's pI is 8.9. Ammonium hydroxide treatment would move the peptide throught the isoelectric point and cause it to aggregate quickly.
You can carefully evaporate the HFIP by a stream of nitrogen to make a dry film before putting it in the lyophillizer. You can leave the film in a desiccator overnight to night to make sure it is dry. Rehydrating the film at pH 5 followed by pH neutralization gives very consistent results if you follow the procedure in here [1] Article Alternative Pathways of Human Islet Amyloid Polypeptide Aggr...
Another alternative is urea or GuHCl denaturation followed by size exclusion chromatography. However,disaggregation is not complete and it requires larger amounts of sample and involves much more sample loss than lyophillization. [2] Article Amyloidogenicity of recombinant human pro-islet amyloid poly...
- Badges
- Science topic
- Similar topics
- Engineering
- Materials Engineering
- Powders