Catalogue / P-21
P-21
Also written as P021, Ciliary neurotrophic factor peptide.
A short peptidomimetic derived from a ciliary neurotrophic factor sequence and carrying an adamantyl modification.
| Class | Signalling and mitochondrial peptides |
| Determination | Peptide analysis, specialist compound |
| Price | 590 USD |
P-21 is identified against a certified reference standard rather than against a published mass, because commercially supplied material varies in composition between suppliers. Purity is reported separately by reversed-phase chromatography at 214 nm and describes the chromatographable fraction only.
| The adamantyl group is what distinguishes this compound from the unmodified parent peptide. Material lacking it is a different molecule with different properties. |
| The modification is strongly lipophilic, so the compound partitions into surfaces and into organic phases in ways the peptide backbone alone would not predict. |
| No mass figure is published on this page because the composition supplied under this name is not consistently documented. Identity is established against a certified reference standard at the time of analysis. |
Every compound fails in its own way. A generic peptide method applied without regard to these specifics produces a number that looks like a result and is not one.
Endogenous peptides with defined sequences, mostly unmodified, where the analytical question is simply whether the delivered material is the stated sequence at the stated mass.
LC-MS identity with deconvolution and RP-HPLC purity at 214 nm.
Where the delivered milligram figure matters rather than the percentage, net peptide content by combustion analysis and water by Karl Fischer are added, and the certificate carries a closed mass balance instead of a single purity number.
| LC-MS identity | Measured mass |
| RP-HPLC purity | Area at 214 nm |
| Net peptide content | Milligrams |
| Water content | Karl Fischer |
| Counter-ion | Ion chromatography |
| Bacterial endotoxins | USP <85> |
What is the molecular weight of P-21?
No molecular weight is published for P-21 on this page, because the composition of commercially supplied material varies between suppliers and an unverified figure on an analytical site is worse than an absent one. Identity is established against a certified reference standard at the time of analysis.
How is P-21 tested for purity and identity?
LC-MS identity with deconvolution and RP-HPLC purity at 214 nm. Purity describes the chromatographable fraction only and is not the same quantity as the peptide mass delivered per vial.
What goes wrong when P-21 is analysed?
The adamantyl group is what distinguishes this compound from the unmodified parent peptide. Material lacking it is a different molecule with different properties.
What does P-21 analysis cost at ANALYTON?
Peptide analysis, specialist compound is priced at 590 US dollars, covering the determinations described on this page. Content, safety and elemental determinations are ordered alongside and are priced separately on the price list.
Other compounds in this class
Updated 2026-09-01. Masses computed at build, not transcribed.