Peptide sample labelling is one of the simplest and most important controls in laboratory work. A sophisticated analytical method cannot rescue a result if the identity of the sample is uncertain.
Use unique identifiers
Each sample should have a unique identifier that remains consistent across labels, worksheets, instrument sequences and final reports. Avoid ambiguous shorthand that can be reused accidentally.
Record lot numbers
The lot number connects the working sample to source documentation and analytical records. If material is subdivided into aliquots, the parent lot should remain traceable.
Label aliquots clearly
Aliquot labels should distinguish individual containers while preserving the original sample relationship. Adding preparation date or aliquot number can improve traceability.
Use durable labels
Labels should remain legible under the expected storage conditions. Condensation, freezing or solvents can damage unsuitable labels or inks.
Separate identity from location
A freezer position is not a reliable sample identity. Storage location can change, while the unique sample identifier should remain constant.
Electronic and physical records should agree
Barcode systems, LIMS records or spreadsheets can improve tracking, but electronic records should match the physical label exactly.
Chain of custody
When samples move between people or laboratories, record transfers so that responsibility and location remain traceable. See the VLS chain-of-custody guide.
Common labelling failures
- Using only initials or dates as sample names.
- Omitting the lot number.
- Writing labels after the work is complete.
- Reusing the same identifier for different aliquots.
- Allowing spreadsheet names and physical labels to diverge.
Frequently asked questions
What is the minimum information on a label?
That depends on the laboratory system, but a unique identifier and traceable link to the lot or source record are fundamental.
Should every aliquot have a separate identifier?
Often yes, especially when storage history or handling may differ.
Are barcodes better than handwritten labels?
They can reduce transcription errors, but only if the barcode system is maintained and records remain accurate.
Why record preparation dates?
Dates help connect sample age and handling history to later analytical results.
Can a freezer location replace a sample ID?
No. Locations can change and should not serve as the primary identity.
Final perspective
Strong sample labelling protects the entire analytical workflow. Unique identifiers, lot traceability and consistent electronic records reduce mix-ups and make peptide research easier to reproduce and audit.
This VLS Peptide article is intended for laboratory and scientific education only.