Peptide Inventory Management Protocol
Systematic protocol for tracking peptide inventory, managing expiration dates, organizing cold storage, and maintaining chain-of-custody documentation for research peptide collections.
Materials Needed
- Spreadsheet application or lab notebook
- Permanent markers (fine-tip, waterproof)
- Waterproof labels or lab tape
- Storage boxes or racks for vial organization
- Thermometer or temperature data logger for cold storage monitoring
- Sealable bags (for grouping related compounds)
Create an Inventory Database
Set up a tracking system (spreadsheet or lab notebook) with the following fields for each compound: compound name, lot number, supplier, quantity (number of vials), mass per vial (mg), purchase date, expiration date, storage location (which freezer/shelf), current status (sealed/reconstituted/depleted), reconstitution date (if applicable), reconstituted concentration, estimated remaining volume, and notes. Each entry should have a unique identifier for cross-referencing with your research logs.
Estimated time: 15-20 minutes
Tips
- • A simple spreadsheet with conditional formatting to highlight approaching expiration dates is highly effective
- • Include a column for COA (Certificate of Analysis) reference — link to or note the COA file for each lot
Catalog Existing Inventory
Audit all peptides currently on hand. Physically inspect each vial and record its details in your inventory database. Verify: the label matches the compound (check lot number against COA), the seal is intact (for unopened vials), storage conditions have been appropriate (was it stored at the correct temperature?), and the expiration date has not passed. Group compounds by status: sealed lyophilized, reconstituted in use, and depleted (to be disposed).
Estimated time: 15-30 minutes depending on collection size
If a lyophilized peptide appears discolored, clumped, or has a compromised seal, note it as potentially degraded
Tips
- • This is a good time to dispose of any expired or compromised compounds
- • Photograph your organized inventory for a visual reference
Organize Cold Storage
Organize your cold storage systematically. Recommended layout: separate zones for lyophilized (freezer, -20°C) and reconstituted (refrigerator, 2-8°C) peptides. Within each zone, group compounds by category (healing, metabolic, cognitive, immune, etc.) or alphabetically. Use small storage boxes or sealable bags to group related vials together. Label each zone clearly. Ensure vials are stored upright (especially reconstituted solutions) to minimize stopper contact.
Estimated time: 15-20 minutes
Never store peptides in a freezer door shelf — temperature fluctuations from frequent opening are highest there
Do not store reconstituted peptides in a frost-free freezer — the defrost cycle creates temperature swings
Tips
- • Place a thermometer or temperature data logger in each storage unit to verify temperature consistency
- • Leave space between vials for air circulation — tightly packed vials may not cool evenly
Label All Vials Clearly
Every vial should be labeled with at minimum: compound name, concentration (for reconstituted peptides), lot number, and date (purchase date for sealed, reconstitution date for reconstituted). Use waterproof permanent markers or pre-printed waterproof labels — standard ink and paper labels degrade in cold, moist environments. Write on both the vial body and the cap for redundancy.
Estimated time: 10-15 minutes for full inventory
Verify labels against COAs before relabeling — mislabeled vials are a serious research integrity issue
Tips
- • Color-code labels by compound category for quick visual identification
- • If space on the vial is limited, use a short code (e.g., 'BPC-250-0601' for BPC-157, 250 mcg/mL, reconstituted June 1st) and maintain a legend in your inventory database
Set Up Expiration and Reorder Alerts
Configure reminders for two critical dates: expiration dates (both manufacturer expiration for sealed vials and 28-day post-reconstitution for opened vials) and reorder points (when supply drops below a threshold). A simple approach: review your inventory spreadsheet weekly and flag any items within 30 days of expiration or below your minimum quantity threshold. For reconstituted peptides, the 28-day clock starts at first needle entry.
Do not use reconstituted peptides beyond 28-30 days even if they appear clear — degradation products may not be visible
Tips
- • Set calendar reminders when you reconstitute a peptide — 'Discard [compound] by [date+28 days]'
- • Maintain a reorder threshold of at least 2 weeks of supply to account for shipping time
Perform Weekly Inventory Checks
Each week, spend 10 minutes reviewing your inventory. Verify: reconstituted peptides are within their use-by date, storage temperatures have remained in range (check thermometer/data logger), no vials show signs of contamination or damage, and current supply levels meet upcoming research needs. Update the 'remaining volume' estimates for actively used compounds. Flag any items approaching expiration for priority use or disposal.
Estimated time: 10 minutes weekly
Tips
- • Combine the weekly inventory check with your weekly research planning session for efficiency
- • First-in, first-out (FIFO) — use older lots before newer ones to minimize waste
Dispose of Expired or Compromised Compounds
Promptly dispose of any peptides that are past expiration, past 28 days post-reconstitution, show signs of degradation (cloudiness, particles, discoloration), or have a compromised seal. Follow the Peptide Lab Safety Protocol for proper disposal. Update your inventory database to reflect the disposal, including the reason for disposal and the date. Never 'extend' the shelf life of an expired or questionable compound.
Do not pour peptide solutions down the drain — follow proper disposal procedures
Tips
- • Keep a disposal log as part of your inventory records — this demonstrates good laboratory practice
- • If you consistently dispose of unused reconstituted peptides, consider reconstituting smaller volumes