Avoiding Contamination on the Bench

Peptide solutions are excellent growth media. Microbial contamination, cross-contamination between compounds and particulate ingress all degrade data quality long before anything becomes visible.

Prepare the space

1. 1Clear the bench, wipe down with a suitable disinfectant and let it dry fully.
2. 2Lay out everything you need before you start so nothing is fetched mid-procedure.
3. 3Work away from air currents, open windows and foot traffic.
4. 4Use gloves and change them between compounds.

Vial discipline

• Disinfect the stopper and allow it to dry before every entry.
• Use a fresh needle for every entry — never park a needle in a stopper.
• Minimise the number of entries by planning aliquots in advance.
• Label immediately; unlabelled tubes are eventually discarded, which wastes material.

Cross-contamination

The commonest cross-contamination route is shared consumables: one diluent vial serving several compounds, or a pipette used without a tip change. Dedicate consumables per compound where possible.

Documentation as a control

Write down what you did while you are doing it — batch, diluent, volume, time, operator. When something goes wrong, the record is what narrows the cause to one step instead of the whole day.