Storage & Handling Reference Guide

RUO — Research Use Only. This document is a reference summary prepared for laboratory use. Compounds described are not approved for human or veterinary administration and have not been evaluated by the FDA for safety or efficacy.

This guide consolidates storage and handling procedures applicable to lyophilized synthetic peptides and small-molecule reference standards distributed by Nexphoria. Procedures reference USP <659>, USP <797>, and ICH Q5C where applicable. Individual compound monographs take precedence over general guidance where conflicts exist.

1.0 Cold-Chain Integrity

Nexphoria shipments are dispatched with validated cold-pack systems designed to maintain 2–8°C for a minimum of 48 hours under typical transit conditions. Temperature indicators (Timestrip or equivalent) are included in each shipment.

Cold-chain arrival assessment criteria
Acceptance criterion on arrival	Cold packs still partially frozen or cool to touch (≤8°C); temperature indicator shows no excursion. Material is accepted without additional testing.
Borderline condition	Cold packs fully thawed but temperature indicator shows no excursion above 15°C. Material may be accepted; document the observation and note in lot log. Consider expedited use.
Excursion — lyophilized peptides	Temperature indicator shows excursion above 25°C for >2 hours. Transfer immediately to −20°C. Retain material; contact Nexphoria within 24 hours with photographic documentation of the temperature indicator. Do not discard without written authorization from Nexphoria QA.
Excursion — reconstituted solutions	Any confirmed excursion above 25°C for >4 hours invalidates reconstituted material. Discard per institutional chemical waste procedure and document.
Warm arrival without indicator	If no temperature indicator is present and material arrives at ambient temperature, treat as excursion and contact Nexphoria QA.

2.0 Long-Term Storage

Storage conditions by material class are summarized below. All durations are from the manufacture date stated on the COA. Store in original sealed vials until use.

Long-term storage conditions by material class
Material Class	Condition	Shelf Life (lyophilized)	Notes
Lyophilized synthetic peptides	−20°C, dark, nitrogen-sealed vial	24 months	Minimize time at ambient temperature during vial handling. See compound monograph for Met-containing peptides.
Small-molecule reference standards	Per compound specification; typically 15–25°C or −20°C if specified on label	Per COA expiry	Confirm storage class on individual product label.
Copper peptides (e.g., GHK-Cu)	2–8°C, protected from light; avoid −20°C (copper coordination may be affected by freeze-thaw)	18 months lyophilized	Do not freeze copper peptide solutions.
Reconstituted peptides	2–8°C in sealed amber container, bacteriostatic water	14–28 days (compound-specific)	See Section 4 and individual compound monograph for duration.

3.0 Reconstitution Media

Selection of reconstitution media depends on intended use duration and multi-dose versus single-use requirements. The three most common options are described below [1, 2].

Reconstitution media selection guide
Diluent	Preservative	Use Case	Maximum Duration
Bacteriostatic water for injection (BAC water)	0.9% benzyl alcohol	Multi-dose laboratory use; re-entry with needle and syringe	28 days at 2–8°C (per USP <797> guidelines for preserved solutions)
Sterile water for injection (SWFI)	None	Single-use aliquots only; immediately aliquot and discard remainder or freeze as single doses	Use within 6 hours if at room temperature; ≤24 hours at 2–8°C without preservative
0.9% sodium chloride injection (normal saline)	None (preservative-free standard)	Buffer-compatible dilutions; analytical working solutions; compounds incompatible with benzyl alcohol	24 hours at 2–8°C without preservative

Do not use tap water, deionized laboratory water, or phosphate-buffered saline (PBS) unless the compound-specific monograph explicitly permits it. Certain peptides are sensitive to phosphate-mediated precipitation or pH extremes outside their stability window.

4.0 Single-Dose vs. Multi-Dose Reconstitution

The choice between single-dose and multi-dose reconstitution protocols has direct implications for contamination risk and stability.

Single-dose versus multi-dose reconstitution comparison
Multi-dose (BAC water)	Reconstitute with bacteriostatic water. Each withdrawal uses a fresh sterile needle. Replace septum cap if damaged. Maximum 28 days from reconstitution at 2–8°C. BAC water preservative inhibits bacterial growth for this period.
Single-use (SWFI)	Reconstitute with sterile water. Withdraw entire volume immediately into individual labeled syringes or vials. Seal and freeze single-use aliquots at −20°C. Use within 30 days (compound-specific). Each aliquot is thawed once and used in its entirety.
Needle gauge for reconstitution	21–23 gauge preferred for reconstitution to minimize coring of the rubber septum and particulate introduction.
Mixing precaution	Direct the diluent stream against the vial wall, not directly onto the lyophilized powder cake. Swirl gently. Do not vortex. Vigorous agitation promotes peptide aggregation and foaming.

5.0 Aliquoting Protocol

Aliquoting divides a reconstituted stock into individual working volumes before freezing, thereby limiting freeze-thaw cycles to one per aliquot [3].

Aliquoting protocol steps
Equipment	Calibrated forward-displacement or air-displacement pipette; sterile polypropylene microcentrifuge tubes (0.5 mL or 1.5 mL); sterile needles and syringes if aliquoting through a sealed septum
Volume per aliquot	Plan aliquot volume based on per-use quantity. Typical volumes: 100–500 µL per aliquot. Label each tube with compound name, lot number, reconstitution date, concentration, and aliquot number.
Labeling	Use cryogenic-rated labels or permanent marker rated for −80°C if applicable. Apply label prior to filling.
Freeze	Place aliquots in a −20°C freezer within 30 minutes of reconstitution. For long-term aliquot storage exceeding 30 days, −80°C is preferred if available.
Thaw	Thaw individual aliquots at 2–8°C for 15–30 minutes or at room temperature for 5–10 minutes. Do not heat. Use immediately after thaw. Discard unused thawed material; do not refreeze.

6.0 Working Concentration Calculation — Worked Example

The following example demonstrates calculation of a working stock concentration from a lyophilized vial with known peptide content.

Given: Vial nominal fill: 5 mg Peptide content (from COA, AAA): 94.1% True peptide mass: 5 mg × 0.941 = 4.705 mg Moisture content (KF): 4.2% → already reflected in AAA peptide content value Target concentration: 2 mg/mL (peptide basis) Volume of diluent required: V = 4.705 mg ÷ 2 mg/mL = 2.35 mL bacteriostatic water Result: Add 2.35 mL BAC water → nominal 2 mg/mL solution Actual concentration: 4.705 mg ÷ 2.35 mL = 2.00 mg/mL

When the COA does not include AAA peptide content, use nominal fill weight ± 10% as an approximation. For precision analytical work, request the AAA certificate from Nexphoria or perform in-house quantification by UV absorbance (if the compound contains an aromatic residue) or gravimetric method.

7.0 Documentation and Logging

Proper documentation is required for traceability from receipt through use. The following fields should be recorded in a laboratory notebook or electronic system for each vial received and reconstituted [4].

Required documentation fields for research peptide handling
Field	Example Entry
Compound name	BPC-157
Lot number	NX-2604-001
Vial serial number (if assigned)	V-047
Receive date	2026-04-10
Arrival condition	Cold pack partially frozen; temperature indicator no excursion
Storage location (lyophilized)	Freezer 3, shelf B, box NX-2026
Reconstitution date	2026-04-15
Diluent used	Bacteriostatic water for injection, 1.0 mL
Calculated concentration	5.0 mg/mL (nominal); 4.705 mg/mL (AAA-corrected)
Aliquot volumes and count	10 × 100 µL aliquots; stored at −20°C, box NX-2026
Operator initials	J.R.

8.0 References

[1] United States Pharmacopeia (2024). USP <659> Packaging and Storage Requirements. In USP–NF. United States Pharmacopeial Convention.
[2] United States Pharmacopeia (2024). USP <797> Pharmaceutical Compounding — Sterile Preparations. In USP–NF. United States Pharmacopeial Convention.
[3] Jiang G., Ni N., Bhatt H., Han Q., Szymanski J., Bhatt D. (2009). Freeze-thaw cycling of proteins: effects on aggregation and activity. PDA Journal of Pharmaceutical Science and Technology, 63(5):359–369. PMID:19921979
[4] ICH Harmonised Guideline Q5C: Quality of Biotechnological Products — Stability Testing of Biotechnological/Biological Products. (1995). International Council for Harmonisation. https://www.ich.org/page/quality-guidelines
[5] Manning M.C., Chou D.K., Murphy B.M., Payne R.W., Katayama D.S. (2010). Stability of protein pharmaceuticals: an update. Pharmaceutical Research, 27(4):544–575. DOI:10.1007/s11095-009-0045-6

References · RUO — Research Use Only · Nexphoria