rPeptide FAQs

Our products are not for human use, they are for research purposes only.

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.

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.

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.

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.

HFIP is Hexafluoroisopropanol

Purity is determined by the ratio of the Beta Amyloid peak area against the total peak area of all the peak areas combined

The lyophilized Beta Amyloid can be stored for at least 2 years at -80°C.

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.

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.

The lyophilized Beta Amyloid can be stored for at least 2 years at -80°C.

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.

The lyophilized Tau is stable for at least 2 years at -80°C. After reconstitution in water, its best to aliquot it (AVOID FREEZE THAW) and store at -80°C. This should be stable for about 1-2 weeks. For longer term, its best to lyophilize it.

After reconstitution in water, its best to aliquot it (AVOID FREEZE THAW) and store at -80°C. This should be stable for about 1-2 weeks. For longer term, its best to lyophilize it.

The lyophilized Tau can be stored for at least 2 years at -80°C.

Our products are not for human use, they are for research purposes only.

Our Tau proteins do not have his tags. Advantage of Tau proteins without his tag vs tau proteins with his tag: 1. Tau protein with his-tag is more likely to be insoluble and hence inamenable for various biochemical assays. This problem will not be there in the Tau protein without any tag. 2. Tau protein with his-tag is more likely to have contaminating proteins which will be coming due to the non-specific nature of interaction between polyhistidine tags and Ni2+ ions. These proteins will interfere with any of the assays or functions of Tau proteins. 3. There are chances that some Nickel too can come as contaminant which can severely alter the functions of Tau. 4. A his-tag Tau can also be immunogenic if used in humans. There can be immune response against the polyhistidine tag which has the potential to act as a linear epitope.

Purity assay for tau is done by SDS only, no mass spec.

Tau 441 is the biggest tau that we have. Since they are made in E.coli they are not phosphorylated.

The lyophilized Tau can be stored for at least 2 years at -80°C.

After reconstitution in water, its best to aliquot it (AVOID FREEZE THAW) and store at -80°C. This should be stable for about 1-2 weeks. For longer term, its best to lyophilize it.

The lyophilized Tau is stable for at least 2 years at -80°C. After reconstitution in water, its best to aliquot it (AVOID FREEZE THAW) and store at -80°C. This should be stable for about 1-2 weeks. For longer term, its best to lyophilize it.

The Alpha Synuclein is full length and has no tag.

Trifluoroacetate is not used during any of the steps in the synuclein purification.

After reconstitution in water, its best to aliquot it (AVOID FREEZE THAW) and store at -80°C. This should be stable for about 1-2 weeks. For longer term, its best to lyophilize it.

The lyophilized Synuclein can be stored for at least 2 years at -80°C.

Our products are not for human use, they are for research purposes only.

The lyophilized Synuclein is stable for at least 2 years at -80°C. After reconstitution in water, its best to aliquot it (AVOID FREEZE THAW) and store at -80°C. This should be stable for about 1-2 weeks. For longer term, its best to lyophilize it.

The lyophilized Synuclein is stable for at least 2 years at -80°C. After reconstitution in water, its best to aliquot it (AVOID FREEZE THAW) and store at -80°C. This should be stable for about 1-2 weeks. For longer term, its best to lyophilize it.

After reconstitution in water, its best to aliquot it (AVOID FREEZE THAW) and store at -80°C. This should be stable for about 1-2 weeks. For longer term, its best to lyophilize it.

The lyophilized Synuclein can be stored for at least 2 years at -80°C.