Frequently Asked Questions

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Beta Amyloids FAQs

How can your Beta Amyloids be used?
Our products are not for human use, they are for research purposes only.
How pure are your recombinant beta-amyloid peptides?
The purity of our recombinant beta-amyloid peptides is consistently >97%. The salt content is ca. 10% of the total weight. The peptide amount specified is the net peptide content. The peptide quantities are estimated by HPLC against a calibration curve derived from quantities estimated by amino acid analyses.
How should your Beta Amyloid be stored after reconstitution in ammonium hydroxide?
After reconstitution in ammonium hydroxide, its best to aliquot it (AVOID FREEZE THAW) and store at -80°C. This should be stable for about 1-2 weeks.or longer term, its best to lyophilize it.
How should your lyophilized Beta Amyloid be stored?
The lyophilized Beta Amyloid can be stored for at least 2 years at -80°C.
I see you use HPLC to check purity. When you say it is >97%, is it strictly based on the peak area of the target peak?
Purity is determined by the ratio of the Beta Amyloid peak area against the total peak area of all the peak areas combined
What does HFIP stand for?
HFIP is Hexafluoroisopropanol
What is the solubility of your recombinant Beta Amyloids?
Beta-amyloid peptides: Resuspend in 1 % NH4OH, at a concentration of 1 mg/ml. Sonicate for 30 seconds after it has gone into solution. The Beta-Amyloid, NaOH salts (A-1155 and A-1165, http://www.rpeptide.com/products/products_7.html) can be resuspended in water.
What is the stability of your lyophilized Beta Amyloid?
The lyophilized Beta Amyloid is stable for at least 2 years at -80°C. After reconstitution in ammonium hydroxide, its best to aliquot it (AVOID FREEZE THAW) and store at -80°C. This should be stable for about 1-2 weeks.or longer term, its best to lyophilize it.
When you state that this vial contains 0.5 mg of peptide, is that precisely weighted or is it possible that there is an excess peptide? When we reconstitute the peptide and dose it by its absorbance at 280 nm, we get much more peptide than expected (more than 200%). Is this normal?
The peptide amount is calibrated chromatographically against known amounts of the product as determined by amino acid analysis. In our experience absorption at 280 nm is extremely low and hence we do not check either the purity or quantitate at 280nm.