Read the technical notes on Bachem products.
CARE AND HANDLING OF AMYLOID PEPTIDES
Bachem offers a broad range of amyloid peptides. Some of these peptides are notorious for their propensity to form scarcely soluble aggregates, which makes reconstitution difficult. As to help our customers, we have compiled a selection of literature references containing protocols for dissolving the peptides. We hope you will find some information, which could be helpful for your experimental work with our peptides.
CARE AND HANDLING OF PEPTIDES
Stringent analytical specifications ensure a complete identification and a high quality standard for every Bachem product. For reconstitution and storage we recommend to follow the guidelines.
The solubility of a peptide is primarily dependent on the physical properties of its amino acids. Amino acids can be classified as acidic, basic, polar uncharged, or non-polar (hydrophobic). Peptides with a high content of non-polar amino acids or polar uncharged amino acids are preferentially solubilized by organic solvents such as DMSO, methanol, propanol, isopropanol, or DMF whereas overall acidic peptides can normally be reconstituted in basic solvents and overall basic peptides in acidic solvents.
CHROMOPHORES / FLUOROPHORES: SPECTRAL PROPERTIES AND CHARACTERISTICS
Bachem offers series of peptide-based enzyme substrates linked to chromophores or fluorophores. The advantage of these chromogenic and fluorogenic substrates is the facile spectrometric detection and analysis of the reaction products. The guide contains some useful information about the various kinds of substrates.
Conversion of a DCHA salt to the Free Acid
Bachem offers a number of N-protected amino acids as DCHA (dicyclohexylammonium) salts. The production of such salts is preferred if the free amino acid is not available in a crystalline form or if the free acid is unstable. In addition, in some cases DCHA salts of derivatives can be purified in a straight-forward process. An example represents the separation of racemates using their diastereomeric salts. However, before starting peptide synthesis, the amino acids have first to be liberated from their DCHA salts.
reversal of inadvertent oxidation of cys-containing peptides
Peptides containing free thiol functions may oxidize yielding dimers or oligomers during storage, even as lyophilizates at low temperatures. Peptides provided as acetates are more sensitive towards Cys oxidation than the corresponding trifl uoroacetates or hydrochlorides.