Catalogue / hCG
hCG
Also written as Human chorionic gonadotropin.
A heterodimeric glycoprotein hormone of roughly 37 kilodaltons, two non-covalently associated chains carrying substantial N and O-linked glycosylation.
| Class | Recombinant proteins |
| Determination | Recombinant protein, content, purity and dimer |
| Price | 650 USD |
hCG 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.
| Glycosylation is heterogeneous by nature, so this molecule has no single mass. Reporting one figure for it is a category error, and content is determined by immunoassay or by chromatographic assay against a reference preparation rather than by mass. |
| The two chains are held together non-covalently. Preparation conditions that dissociate them destroy the active species while leaving both chains present, so a result on the chains says nothing about the dimer. |
| Potency is expressed in international units against a reference preparation, not in milligrams of protein. The two figures are not convertible and both belong on a certificate. |
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.
Expressed rather than synthesised. The failure modes are different: aggregation, deamidation, oxidation and truncation, none of which a single purity number captures.
RP-HPLC purity, size exclusion chromatography for dimer and higher aggregate, and where required a charge-variant separation. Aggregate is reported as a separate figure because a dimer is chemically still the same protein.
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 hCG?
No molecular weight is published for hCG 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 hCG tested for purity and identity?
RP-HPLC purity, size exclusion chromatography for dimer and higher aggregate, and where required a charge-variant separation. Aggregate is reported as a separate figure because a dimer is chemically still the same protein. Purity describes the chromatographable fraction only and is not the same quantity as the peptide mass delivered per vial.
What goes wrong when hCG is analysed?
Glycosylation is heterogeneous by nature, so this molecule has no single mass. Reporting one figure for it is a category error, and content is determined by immunoassay or by chromatographic assay against a reference preparation rather than by mass.
What does hCG analysis cost at ANALYTON?
Recombinant protein, content, purity and dimer is priced at 650 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.