Peptide stability table (revision 49)

The peptide stability table collects reported storage conditions and stability intervals for compounds covered on this wiki. It is a navigational and comparative aid rather than a source in its own right: every figure in it is attributable to labelling or to a published study, and the two are not equivalent evidence.

Stability is a property of a formulation in a container under conditions, not of a molecule. The same peptide may carry a 36-month shelf life as a manufactured product and no meaningful stability claim at all as a lyophilised research powder in an unspecified vial, because nobody has run the study.^[1] Where the table records a figure for a research compound, that figure is almost always extrapolated from a related product or from a small published study, and the notes column says so.

Filter by compound name, or by storage class. Sorting is available on every column.

Lyophilised

Conditions and interval reported for the dry solid in its sealed container. A lyophilised peptide is far more stable than the same peptide in solution, because the degradation pathways that matter — deamidation, oxidation and aggregation — all require water or mobility.^[2]

Reconstituted

Conditions and interval after dissolution. This is the column with the weakest sourcing across the table, and the one carrying the maintenance banner: for approved products it comes from labelling, and for research compounds it is usually an extrapolation.

Diluent

What the figure applies to. Bacteriostatic water and unpreserved water are not interchangeable for the purpose of a storage interval, because the interval for a multi-puncture container depends on the preservative.

Light

Whether photodegradation is reported as significant. Tryptophan- and tyrosine-containing sequences are the usual concern.

Basis

Whether the row rests on manufacturer labelling, a published stability study, or an extrapolation. Rows marked extrapolated should not be cited as evidence about the compound named.

Four differences between sources make two stability figures incomparable even when both are honestly reported.

The specification differs. "Stable for 28 days" means "remained within the specification" and specifications differ. A limit of 95% of label potency and a limit of 90% produce different intervals from identical data.

The assay differs. A stability-indicating HPLC method that resolves the principal degradant reports loss that a method which co-elutes it does not. Method validation is what establishes that a method is stability-indicating, and research-compound figures rarely state whether it was.^[1]

The container differs. Adsorption to glass, extractables from a stopper, and headspace oxygen all affect degradation rate. A figure obtained in a Type I glass vial with a coated stopper does not transfer to an uncoated one.

The temperature history differs. A nominal 2–8 °C figure assumes 2–8 °C throughout. Real distribution includes excursions, and the mean kinetic temperature of a shipment can exceed its nominal condition substantially.^[1]

It does not tell a reader whether a specific vial is sound. Stability data describes a formulation under conditions; it says nothing about a particular container that has been through an unknown distribution history. Nor does it address:

• sterility, which is a property of the process and container-closure integrity, tested under USP <71> rather than by a stability study;^[3] storage and packaging requirements are set out separately again;^[4]
• endotoxin, which does not decrease on storage and is tested under USP <85>;
• identity, which is what mass spectrometry establishes and no stability figure implies;
• the label claim, which is a mass-balance question.

• Cold chain
• Temperature excursion
• Lyophilisation
• Beyond-use date
• Peptide aggregation
• Deamidation

• Wang W. "Lyophilization and development of solid protein pharmaceuticals." International Journal of Pharmaceutics 203(1–2):1–60 (2000).