Peptide Library Service: Storage & Handling Guidelines

DATE: November 21, 2014

Organic chemistry is vast and is also useful in the production of different peptides. Researches are going on for getting its prominence in fundamental physiological and biochemical functions of life. They have recently identified techniques for manufacturing and studying new applications for it.

Peptide Library Service is one such technique that could study the protein and its synthesis. It contains a great number of systematic combinations of amino acid and provides a powerful tool for drug design, protein-protein interactions, and other biochemical as well as pharmaceutical applications. It’s a challenging program and need certain precautions in handling and storing. Only proper peptide handling and solubilization can make a successful bioassay project.

Peptide solution’s shelf life is limited, especially the peptides containing C, M, N, Q and W. To prolong the storage life of the peptides in solution, keep it in a dry, cool and dark place. A sterile buffer with a pH of around 5-6 could be helpful. Store at 4 degree centigrade and a much colder place that is devoid of bright light. Avoid use of frost free freezers as repeated freeze-thaw cycles are deleterious to peptides. Whereas dry peptides can exist for days or weeks under normal room temperature. But the solid peptides shows much more contamination towards moisture. It is advised to warm the vial till room temperature before opening. After taking the desired quantity, re-seal the vial and then store in the cold storage.

Peptide Dissolution
There is no universal solvent for solubilizing all lyophilized peptides, whilst maintaining their integrity and compatibility in biological assays. Solubility has been a problem for many of the Peptide Library Service provider. So, it’s necessary to use a series of solvents for checking the dissolution of the peptide. You can adopt three best approaches to find the answer for the solubility problem of the peptide.

Approach 1: Dissolve the peptide in sterile distilled water or dilute acetic solution to give higher concentration. Later it will be diluted with appropriate buffer. Even sonication can be used to increase the dissolution.

Approach 2: If the peptide remains insoluble, check the proportion of hydrophobic, hydrophilic and overall charge on the neutral pH. If there is a net charge at neutral pH, then add dilute acetic acid or dilute aqueous ammonia or ammonium bicarbonate. Still the sample refuses to dissolve, then try alternative solvents for the same peptide.

Approach 3: If the peptide sequence has little or no charge at any pH, add acetonitrile, ethanol, dimethylformamide (DMF) dimethyl sulphoxide (DMSO), and chaotropic salts for better dissolution of most peptides. It depends upon the choice and on the compatibility of reagents with the peptide.

Once you receive your peptide from Peptide synthesis company, follow the above mentioned storage and dissolution approaches. As these are more susceptible to degradation by proteases of bacterial or microbial origin. You must prefer an ideal container for peptide manipulation. Use high quality polypropylene vials and specialist glass to lessen the storage problem. All these suggestions will surely help with long term storage of the peptide library.

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We synthesize virtually every antimicrobial peptide (AMP), such as LL-37, for Host Defense Peptide studies. Contact us today for pricing on your specific AMP of interest.