Peptide vials are sterile, airtight containers that protect your peptides from moisture and other contaminants. They are used to store and re-use peptides after they have been opened, and can be purchased in various sizes depending on your needs. When choosing peptide vials, you should look for a container that is clean, chemically inert, optically clear and strong. Glass and polypropylene are both good choices. Glass is better for handling organic solvents while plastic is best for water solutions.
A peptide vial should be properly labeled to ensure that you don’t accidentally mix your peptides with something else. You should also write down what the contents are and how much of each peptide there is in the vial. This will help you prepare your injections correctly. It is also important to wipe down the area where you plan on injecting your peptides before you begin. This will prevent bacteria and other particles from entering the needle and making you ill after your injection.
Once you have a clean and dry injection site, it’s time to start preparing your syringe. First, wipe down the syringe with a sterile wipe and remove any protective cap from it. You will also need to select the correct needle length and gauge for your injections. It’s important that you don’t choose a needle size that is too big or too small, as this can affect your dosage and injection technique. Lastly, you will need to load the syringe with the correct amount of peptide from your vial.
When you’re ready to re-use your peptides, remember to add the proper amount of bacteriostatic water to each vial. For example, if your peptide is in a 3mg vial and you need to reconstitute it for use, then you will need 1mL of bacteriostatic water for each 10mg of the peptide. The reconstituted peptide will now have the same measurements as the original vial.
Peptides stored in solution have a very limited shelf life and are susceptible to bacterial degradation. GenScript does not recommend that peptides be stored in solution for extended periods of time, and recommends only short-term storage. If peptides are to be stored in solution, a sterile buffer at pH5-6 should be used and the peptide should be divided into smaller aliquots for storage. The aliquots should be kept at -20°C and should avoid any repeated freeze-thaw cycles.
The most important factor in successful LC-MS peptide analysis is to minimize peptide analyte adsorption on sample vial surfaces. A number of studies, including one by Van Midwoud et al, have demonstrated that poor study performance is often linked to vial contamination. Other studies have shown that adsorption can lead to nonlinear calibration curves and even limit the detection of the analyte. To reduce this issue, a variety of techniques have been used including the addition of adsorbents such as the metal chelator EDTA and high salt concentrations. However, this method only offers a partial solution and may not be ideal for all applications.