This series takes a certificate of analysis one line at a time and asks what each line measures. This one takes the line that measures nothing — the row labeled Storage Conditions — and the question that row raises on its own: if the document says refrigerated, what does it say about how the material ships?
The one row with no method and no result
Every entry in the test table has four fields: Test Item, Specification, Method, Result. Water Content by Karl Fischer. Peptide Purity by HPLC. Residual Solvents by GC per USP <467>. Each row names a method and reports what it found.
Below that table sit three more rows — Storage Conditions, Shelf Life, Conclusion — with two fields, not four. On the two lots published at www.primesciencesupply.com/certificates that this piece uses as examples (COA-PBL-010326-MOTSC, lot MOTSC-122825, and COA-PBL-010326-GLOW, lot GLOW-122825), the storage row reads Store refrigerated at 2-8 °C and the shelf life row 24 months from manufacture date.
No method. No result. The storage line is an instruction the document carries, not a property the document measured. That is not a flaw — release certificates are built this way — but everything above that row is a measurement and that row is a decision, and a reader should know which one is in front of them.
"Refrigerated," "cool," "ambient" — the words are defined terms
USP General Chapter <659>, Packaging and Storage Requirements, defines the vocabulary: Refrigerator, 2°–8°; Cold, not exceeding 8°; Cool, 8°–15°; Excessive heat, above 40°. Controlled room temperature is 20°–25°, with the mean kinetic temperature not to exceed 25°, excursions between 15° and 30° allowed in warehouses and during shipping, and transient spikes up to 40° permitted if they do not exceed 24 hours.
Room temperature, by contrast, <659> defines as the temperature prevailing in a working environment — a description, not a limit. ICH Q1A(R2) goes further: terms such as "ambient conditions" or "room temperature" should be avoided in a storage statement. A supplier who writes "store cool and dry" has invoked a defined range; one who writes "keep at room temperature" has invoked whatever the room happens to be.
Storage and transit are two different questions
ICH Q1A(R2) treats them separately, in one sentence worth quoting: data from the accelerated storage condition "can be used to evaluate the effect of short term excursions outside the label storage conditions (such as might occur during shipping)." For a drug substance intended for refrigerated storage, that guideline's accelerated condition is 25 °C ± 2 °C / 60% RH ± 5% RH for six months, and "significant change" is defined there as failure to meet the specification.
Read the structure rather than the numbers. A label that says 2–8 °C is a long-term storage condition; what a few days outside it does is a separate study, with its own condition, duration and acceptance criterion. One does not imply the other — and a certificate of analysis reports neither study. A COA describes one lot at the moment it was tested.
Our shipping conditions are therefore published separately and stated plainly: we do not use dry ice, refrigerants, or temperature-controlled service (shipping policy). Better that sentence than a storage line left to imply a cold chain the operation does not run.
The row that names a physical form, and the method that cannot check it
Reading all four fields of the Appearance row changes the answer. On the two published lots:
- COA-PBL-010326-MOTSC (lot MOTSC-122825) — Specification: White to off-white crystalline powder. Method: Visual Inspection. Result: Conforms.
- COA-PBL-010326-GLOW (lot GLOW-122825) — Specification: Blue to blue-green lyophilized powder. Method: Visual Inspection. Result: Conforms.
The Specification column does state a solid form. The Method column is where the four fields stop lining up: visual inspection establishes color and gross description, not solid-state form. The techniques that do are X-ray diffractometry and differential scanning calorimetry — Sundaramurthi and Suryanarayanan (Advanced Drug Delivery Reviews, 2011) review that pairing for frozen and freeze-dried systems, and report that crystallization of formulation components may occur during freeze-drying. Neither method is on our panel.
The two words are not interchangeable either: lyophilization is a drying process, crystalline is a solid-state form. Only one of those rows makes a solid-state claim, and it is the one checked by eye.
That decides which literature applies. Hancock and Zografi (Pharmaceutical Research, 1994) measured glass transition temperature against water content and report a rapid initial drop as water is absorbed, then a leveling off — water acting as a plasticizer much as other small molecules do rather than through a specific interaction. By its own title, that paper is about amorphous and partially amorphous solids. Manning and colleagues (Pharmaceutical Research, 2010) review instability of protein pharmaceuticals including the dried state — proteins, not our catalog. Whether either describes a given lot of ours turns on a determination our certificate does not contain.
The water number stays what it is: 2.5% on the MOTS-c lot and 2.9% on the GLOW lot by Karl Fischer, against a specification of NMT 5.0%. (The pharmacopeial procedure for titrimetric water determination is USP <921>; the document names the technique, not the chapter.) A real result by a named method — and not a stability conclusion, since reading it against that literature would require the form.
Re-test date and expiry date are not one field
Our certificates print one field, "Retest / Expiry Date"; ICH keeps the ideas apart, a re-test period being derived from stability information. On both lots above that field reads 12/28/2027 — exactly 24 months after the printed production date of 12/28/2025. It is arithmetic carried down from the shelf-life row. The document does not claim otherwise, and neither do we.
What to ask any supplier, including us
- Is the storage statement backed by a stability study — at what condition, for how long?
- Does the panel include water content, by what method, and what was this lot's result?
- Was the physical form determined instrumentally, or only by visual inspection?
- Is the date on the document a re-test date or an expiry date, and derived from what?
- What are the shipping conditions, in writing, and where are they published?
A supplier who answers "yes, and here it is" is describing material. One who answers that the material is extremely stable, without saying what was measured, is describing nothing. Questions to [email protected] are answered in the terms this article uses.
Where our catalog sits
The certificates discussed here are published at www.primesciencesupply.com/certificates and the shipping conditions at www.primesciencesupply.com/shipping-policy. The first piece in this series covers the identity test our certificates do not include: What a Peptide Certificate of Analysis Does Not Tell You. A catalog reference: Selank (10 mg), a synthetic heptapeptide analog of tuftsin extended with a Pro-Gly-Pro sequence.
Research Use Only. Not for human or veterinary use. These products are not drugs and have not been approved by the FDA for any purpose. These statements have not been evaluated by the FDA. Prime Science Supply does not provide guidance on preparation, administration, or dosage.