The testing program behind each lot

Every lot is submitted for analytical testing before it enters inventory, and the matching certificate travels with the order. This page explains what each method measures, what it does not measure, and how to read the resulting document.

Verify a lot Request a certificate

The lot lookup is live but its record set is empty until signed reports are loaded, so send us the lot number printed on your vial in the meantime.

HPLC

Purity method on every lot

Identity confirmation

LAL

Endotoxin screening

COA

Lot-matched with each order

Four analytical layers, and the limits of each

HPLC purity

High-performance liquid chromatography separates the components of a sample by how strongly they interact with a stationary phase. The area of the main peak relative to total peak area is reported as a purity percentage.

What it misses — A purity figure says nothing about which molecule the main peak is. It also under-reports anything that does not absorb at the detection wavelength or does not elute from the column — inorganic salts, residual solvents and endotoxin are all effectively invisible to it.

Mass spectrometry identity

Mass spectrometry measures the mass-to-charge ratio of ionised material. Comparing the observed mass against the mass calculated from the intended sequence confirms that the main component is the molecule named on the label.

What it misses — A matching mass does not prove the amino acid order, and it cannot distinguish isomers or most stereochemical differences. Sequence-level confirmation requires fragmentation analysis or sequencing, which is a separate test.

LAL endotoxin testing

The limulus amebocyte lysate assay detects bacterial endotoxin — lipopolysaccharide fragments from Gram-negative bacteria — and reports it in endotoxin units per milligram.

What it misses — It detects endotoxin specifically, not sterility, not fungal contamination, and not exotoxins. A low endotoxin figure does not mean a vial is sterile, and certain sample matrices can inhibit or enhance the assay unless a spike recovery control is run.

Appearance, water content and closure

Visual inspection covers cake structure, colour and the presence of particulates; Karl Fischer titration measures residual moisture, which drives long-term stability of a lyophilized cake.

What it misses — These are physical checks. A well-formed cake with low moisture can still be the wrong compound or a degraded one — appearance never substitutes for the analytical tests above.

Reading a certificate of analysis

A certificate is only useful if you can check it. These are the fields to look at, in the order worth checking them.

Field	What to check
Product name and lot number	Must match the label on the vial you received. If they differ, stop and query it.
Manufacture and test dates	A test date long after manufacture, or a certificate reused across lots, both warrant a question.
Testing laboratory	A named laboratory, distinct from the manufacturer, is what makes the result independent.
Method for each result	Every number should name the method that produced it. A purity figure with no method behind it is not verifiable.
Specification versus result	The specification is the threshold; the result is the measurement. Both should be printed, side by side.
Chromatogram and spectrum	The raw trace lets you see peak shape and shoulders that a single summary percentage hides.
Signature and date	An unsigned certificate is a data sheet, not a certificate.

Sample certificates are not published here. Rather than show an illustrative document with invented figures, we will publish real annotated lot reports once they are available.

Research use only

Analytical testing describes the material in the vial. It is not an assessment of safety or suitability for any use in humans or animals, and none is implied. All material is supplied strictly for laboratory research.