IGF-2 LR3

1 Identity

Asserted to be an analog of insulin-like growth factor 2 bearing the Long-Arg3 modification borrowed from IGF-1 LR3. Whether that molecule has ever been characterized as supplied is the substance of this record. Two sellers list it, one as 'IGF-2 LR3 1200MCG' and one as 'IGF-2 LR3 Peptide'.

Sequence

Not established. The 'LR3' modification is defined for IGF-1: an arginine substitution at position 3 plus a 13-residue N-terminal extension, giving an 83-residue analog. Applying that nomenclature to IGF-2 is a seller construction, not a characterized molecule — no primary literature describing a Long-Arg3 IGF-2 was located, and no supplier discloses a sequence. The name describes A modification pattern, not A known substance.

Molecular formula

Not disclosed by any seller and not established in the literature.

Average mass

Not disclosed, and not derivable without a sequence.

Monoisotopic mass

Not available.

Salt / variant note

IGF-1 LR3, already recorded here, which is the real and characterized molecule this name is modeled on — 83 residues, approximately 9,111 Da. IGF-2 itself, the 67-residue wild type. IGF-1 des and IGF-1 full length, both in this catalog. The risk is not subtle: a seller with no IGF-2 LR3 has every incentive to ship IGF-1 LR3, which is cheaper, real, and indistinguishable to a buyer who never sees a sequence.

2 Class & testing panel

Form

Single article

Testing panel

Special-class panel — panel definition

3 Primary sources & evidence

The index reports the design and provenance of the literature, not a conclusion about effect.

Effectively none. The absence is the record.

4 Storage & specification

Storage

Not assigned. The article is not offered.

Shelf life

Not assigned. The article is not offered.