Documentation

Quality & Testing

How material is verified before it is listed, how certificates of analysis are produced, and how to read one.

From incoming lot to listed product

Cryo Reagents does not manufacture. We buy finished lots and then pay an independent laboratory to analyse them, rather than relying on the certificate the manufacturer supplies with the shipment. The laboratory is chosen by us, paid by us, and has no stake in the outcome — which is the only thing that makes a purity figure worth reading.

The analysis is destructive: vials are consumed by the testing and never sold. A lot that arrives without a certificate we commissioned is not listed, and the database refuses to list it — a size cannot be made purchasable until its certificate and lot number are on file.

01
Incoming material
Each lot is received against its manufacturing documentation and held until its paperwork is complete. Nothing is listed as available without a certificate of analysis for that lot.
02
Independent analysis, at our cost
Vials are drawn from the lot and sent to an independent analytical laboratory that we commission and pay. The laboratory has no commercial interest in the result, and no relationship with the manufacturer.
03
Check against the shipment
The certificate is checked against what arrived: compound, lot number, and stated size. A lot that arrives without a matching certificate is not listed for sale.
04
Publication
The certificate is published against the specific lot held in stock and linked from the product page. When stock turns over to a new lot, the certificate on the page changes with it.

What is measured

The panel we commission covers identity, purity, and net content — what the material is, how much of it is the stated compound, and how much is in the vial.

It does not cover endotoxin, microbial contamination, or elemental impurities. Those are separate determinations we do not currently purchase, and nothing on this site should be read as a claim about them. If that changes, this page changes with it.

Analytical methods and what each determines
Method	Determines	Notes
RP-HPLC	Chromatographic purity	Reversed-phase high-performance liquid chromatography separates the sample by hydrophobicity. Purity is reported as the area of the main peak as a percentage of total peak area at the stated wavelength.
Mass spectrometry	Identity	The observed molecular mass is compared against the theoretical mass for the sequence or formula. A match within instrument tolerance confirms the material is what the label says.
Karl Fischer or loss on drying	Water content	Residual water in a lyophilised solid. This matters because a stated net peptide mass is otherwise ambiguous.
Appearance and solubility	Physical conformity	Visual inspection against the expected form, colour, and dissolution behaviour.

How to read a certificate of analysis

A certificate of analysis records what a laboratory measured, on a specific lot, on a specific date, using a stated method. It describes the material and nothing else. It is also a document produced by a party with an interest in the result, which is why the chromatogram and the mass spectrum matter more than the summary figures. Read it field by field:

Product name and CAS number: Confirm both match the product you ordered. The CAS number is the unambiguous identifier; names and abbreviations vary between suppliers.
Lot number: Must match the lot printed on the vial you received. A certificate for a different lot describes different material.
Date of analysis: When the measurements were taken. Read alongside the retest date rather than on its own.
Purity (%): The main peak as a percentage of total peak area, under the stated method and wavelength. Purity figures from different methods are not directly comparable.
Molecular weight — theoretical and observed: The two should agree within the instrument’s tolerance. A discrepancy beyond that is the single most important thing to query.
Water content (%): Subtract this from gross mass when your calculation depends on net solid content.
Chromatogram and mass spectrum: The underlying traces. A certificate that reports numbers without the traces cannot be independently checked.
Laboratory identity and signature: Which laboratory performed the analysis, and who signed for it.

If a certificate and a vial disagree, or a figure looks wrong, contact us with the order number and lot number before using the material.

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From incoming lot to listed product

Incoming material

Each lot is received against its manufacturing documentation and held until its paperwork is complete. Nothing is listed as available without a certificate of analysis for that lot.

Independent analysis, at our cost

Vials are drawn from the lot and sent to an independent analytical laboratory that we commission and pay. The laboratory has no commercial interest in the result, and no relationship with the manufacturer.

Check against the shipment

The certificate is checked against what arrived: compound, lot number, and stated size. A lot that arrives without a matching certificate is not listed for sale.

Publication

The certificate is published against the specific lot held in stock and linked from the product page. When stock turns over to a new lot, the certificate on the page changes with it.

What is measured

The panel we commission covers identity, purity, and net content — what the material is, how much of it is the stated compound, and how much is in the vial.

Analytical methods and what each determines
Method	Determines	Notes
RP-HPLC	Chromatographic purity	Reversed-phase high-performance liquid chromatography separates the sample by hydrophobicity. Purity is reported as the area of the main peak as a percentage of total peak area at the stated wavelength.
Mass spectrometry	Identity	The observed molecular mass is compared against the theoretical mass for the sequence or formula. A match within instrument tolerance confirms the material is what the label says.
Karl Fischer or loss on drying	Water content	Residual water in a lyophilised solid. This matters because a stated net peptide mass is otherwise ambiguous.
Appearance and solubility	Physical conformity	Visual inspection against the expected form, colour, and dissolution behaviour.

How to read a certificate of analysis

Product name and CAS number

Confirm both match the product you ordered. The CAS number is the unambiguous identifier; names and abbreviations vary between suppliers.

Lot number

Must match the lot printed on the vial you received. A certificate for a different lot describes different material.

Date of analysis

When the measurements were taken. Read alongside the retest date rather than on its own.

Purity (%)

The main peak as a percentage of total peak area, under the stated method and wavelength. Purity figures from different methods are not directly comparable.

Molecular weight — theoretical and observed

The two should agree within the instrument’s tolerance. A discrepancy beyond that is the single most important thing to query.

Water content (%)

Subtract this from gross mass when your calculation depends on net solid content.

Chromatogram and mass spectrum

The underlying traces. A certificate that reports numbers without the traces cannot be independently checked.

Laboratory identity and signature

Which laboratory performed the analysis, and who signed for it.

If a certificate and a vial disagree, or a figure looks wrong, contact us with the order number and lot number before using the material.