AssayIndex
Growth-hormone axis peptides

IGF-1 LR3

Long R3 IGF-1 · LR3 IGF-1 · C400H625N111O116S9 · monoisotopic 9105.2412 Da. The index holds 86 assay reports on this compound across 18 batches from 14 suppliers.

86 reports18 batchesmedian 97.75 %index spec 95.0 %
Section 1

Analytical fingerprint

Hand-authored chemistry. These properties describe the substance and do not change when a record is added.

IGF-1 LR3 is a recombinant 83-residue protein with three disulfide bonds, and it does not belong in an RP-HPLC purity workflow designed for synthetic peptides. The index reports it anyway, because it is submitted, but every LR3 record carries a method-suitability note: RP-HPLC on a C18 column measures hydrophobic heterogeneity, not correct folding, and a correctly-massed, 98 %-pure LR3 lot can still be entirely scrambled. SEC and non-reducing/reducing comparison are the informative methods and only two of the six index labs offer them. LR3 purity figures here should be read as an upper bound.

Molecular formula
C400H625N111O116S9
Monoisotopic mass
9105.2412Da
Average mass
9111.50Da
Residues
83
Nominal retention (RG-2, 30 min)
16.92min
Retention window
0.50min
Counter-ion as usually shipped
acetate
Typical label claims
0.1 mg · 1 mg
Analytical difficulty (index scale)
1.60 — hard
Purity is a defined quantity
YES
Section 2

Representative chromatogram

Drawn from this page's own medians. Not a scan, not an illustration, and not any single report.

01560312046806240 IGF-1 LR316.92 min · 97.75 % 17.5414.9820.12 same trace · ×100 vertical expansion, baseline-corrected · main peak off-scale reporting threshold 0.05 % area 05101520253035 Retention time (min) Response (mAU)
Figure 1. A representative IGF-1 LR3 trace on the index reference method RG-2, constructed from this page's own numbers: the main peak carries the index median purity of 97.75 % area at the nominal retention time of 16.92 min, and each impurity peak carries the median area the index has observed for that named species at its characteristic retention offset. It is not a scan of any single report — every individual record's own chromatogram is on its own page. The lower panel is the same trace at a stated vertical expansion, baseline-corrected, so the impurities are visible; the main peak runs off-scale there by design. Baseline noise is seeded from the compound slug.
Section 3

What the index has observed

Arithmetic over the 86 records the index holds. Aggregates on this page are computed over the records the index holds, which are not a random sample of the material on the market. Lots that get tested are lots someone chose to test. Read every figure here as a description of this dataset rather than as an estimate of a population.

Median purity 97.75% n=86
Interquartile range 1.03pp n=86
Minimum 96.06% n=86
Maximum 99.51% n=86
Pass rate vs spec 100.0% n=86
Median recovery vs claim 98.0% n=49
Median water 4.47% n=86
Median |mass error| 2.3ppm n=75
0481292.093.094.095.096.097.098.099.0100.092.00–92.25 %: n=092.25–92.50 %: n=092.50–92.75 %: n=092.75–93.00 %: n=093.00–93.25 %: n=093.25–93.50 %: n=093.50–93.75 %: n=093.75–94.00 %: n=094.00–94.25 %: n=094.25–94.50 %: n=094.50–94.75 %: n=094.75–95.00 %: n=095.00–95.25 %: n=095.25–95.50 %: n=095.50–95.75 %: n=095.75–96.00 %: n=096.00–96.25 %: n=196.25–96.50 %: n=096.50–96.75 %: n=496.75–97.00 %: n=797.00–97.25 %: n=797.25–97.50 %: n=1497.50–97.75 %: n=897.75–98.00 %: n=1198.00–98.25 %: n=1098.25–98.50 %: n=998.50–98.75 %: n=498.75–99.00 %: n=799.00–99.25 %: n=199.25–99.50 %: n=299.50–99.75 %: n=199.75–100.00 %: n=0median 97.75 Purity (% area) Reports
Figure 2. Purity distribution across all 86 IGF-1 LR3 records. Dashed line is this compound's median (97.75 %); the solid vertical is the index acceptance specification for the growth-hormone axis peptides class (95.0 %). Domain is fixed at 92–100 % on every purity histogram on this site so that compounds can be compared by eye — a wide distribution here is a hard compound, a narrow one is an easy one, and neither is a statement about the suppliers.
Section 4

By supplier

Suppliers with fewer than two purity records on this compound are omitted from the figure rather than drawn as a line. The full table, including the thin cells, is on the by-supplier page.

95.896.597.197.898.599.199.8SWBSWB: Q1 96.93, median 97.13, Q3 97.35, n=15outlier 96.06outlier 98.19outlier 98.31outlier 98.43n=15WXTWXT: Q1 96.78, median 96.93, Q3 97.44, n=13n=13CPCCPC: Q1 97.44, median 97.73, Q3 97.91, n=12n=12WWBWWB: Q1 98.78, median 98.90, Q3 99.21, n=12n=12GGPepsGGPeps: Q1 97.59, median 98.11, Q3 98.36, n=9n=9TFCTFC: Q1 97.53, median 97.77, Q3 97.98, n=6n=6HJHJ: Q1 97.54, median 97.86, Q3 97.94, n=6n=6SGNSGN: Q1 97.45, median 97.64, Q3 97.83, n=4n=4QYBQYB: Q1 98.53, median 98.65, Q3 98.80, n=3n=3JEEPJEEP: Q1 97.89, median 98.13, Q3 98.38, n=2n=2 Purity (% area)
Figure 3. IGF-1 LR3 purity by supplier, ordered by coverage. The vertical line is the index acceptance specification. Boxes that overlap are suppliers this dataset cannot separate, and most of them overlap.

Full per-supplier table with n= caveats →

Section 5

Characteristic impurities and degradants

The left three columns are authored chemistry — what this molecule characteristically carries and where it elutes. The right three are what the index has actually reported.

Named speciesΔRT (min, RG-2)Δ mass (Da)Seen inMedian % areaMax % area
des-13-residue N-extension (native IGF-1)-2.24-1441.712100%0.182.06
disulfide-scrambled isomer+0.62mass-identical100%0.541.67
truncated (1-70)-1.94-1385.688100%0.271.79
aggregated dimer+3.20+9105.241100%0.151.52
oxidised Met59 (+16 Da)-0.72+15.99597%0.221.79

Degradation pathways

  • disulfide scrambling — three disulfides, many wrong ways to pair them
  • aggregation on freeze–thaw
  • deamidation at multiple Asn

Full impurity profile, with what each named species implies about the synthesis →

Section 7

Quarterly coverage

QuarterReportsMedian purityRange
2024-Q11098.9598.63–99.51
2024-Q20n<3—
2024-Q32n<397.51–98.56
2024-Q41n<3—
2025-Q11097.7797.23–98.07
2025-Q21n<3—
2025-Q31597.4496.50–98.80
2025-Q41797.1796.06–98.63
2026-Q1897.7896.78–98.95
2026-Q22197.8097.16–98.47
2026-Q31n<3—

Quarter-by-quarter detail →

Section 8

Most recent records

The 25 most recent IGF-1 LR3 records of 86.
ReportSupplierLotLabQuarterPurity %Water %Recovery %ProvenanceFlagsResult
AX-2026-042238HomopeptideHOMO-2607-P1246PeptideMeter2026-Q398.346.3895.0Laboratory-retained0PASS
AX-2026-042639GGPepsGGPE-2604-K8140Janoshik2026-Q298.112.5788.0Supplier-supplied1MARGINAL
AX-2026-043299CPCCPC-2512-S2394VendorInvestigate2026-Q297.291.7796.7Buyer-sourced1FAIL
AX-2026-043296CPCCPC-2512-S2394VendorInvestigate2026-Q297.802.3091.3Buyer-sourced0PASS
AX-2026-042636GGPepsGGPE-2604-K8140Janoshik2026-Q298.392.26—Supplier-supplied0PASS
AX-2026-042642GGPepsGGPE-2604-K8140Janoshik2026-Q298.182.54—Supplier-supplied0PASS
AX-2026-043291CPCCPC-2512-S2394PeptideMeter2026-Q298.182.7499.7Supplier-supplied0PASS
AX-2026-042643GGPepsGGPE-2604-K8140Janoshik2026-Q298.102.36109.0Laboratory-retained0PASS
AX-2026-042637GGPepsGGPE-2604-K8140Janoshik2026-Q298.472.20—Supplier-supplied0PASS
AX-2026-043298CPCCPC-2512-S2394Janoshik2026-Q297.282.61—Supplier-supplied0PASS
AX-2026-042641GGPepsGGPE-2604-K8140Janoshik2026-Q297.592.55—Supplier-supplied0PASS
AX-2026-043302CPCCPC-2512-S2394Janoshik2026-Q298.072.91—Supplier-supplied0PASS
AX-2026-043300CPCCPC-2512-S2394VendorInvestigate2026-Q297.161.8097.5Laboratory-retained0PASS
AX-2026-043301CPCCPC-2512-S2394Janoshik2026-Q297.552.33104.5Laboratory-retained0PASS
AX-2026-042640GGPepsGGPE-2604-K8140Janoshik2026-Q297.461.89—Supplier-supplied0PASS
AX-2026-042644GGPepsGGPE-2604-K8140PeptideMeter2026-Q298.362.46109.0Supplier-supplied0PASS
AX-2026-043295CPCCPC-2512-S2394Janoshik2026-Q297.752.77—Supplier-supplied0PASS
AX-2026-042638GGPepsGGPE-2604-K8140Medutest2026-Q297.472.6996.0Supplier-supplied0PASS
AX-2026-043294CPCCPC-2512-S2394Janoshik2026-Q297.492.21106.2Supplier-supplied0PASS
AX-2026-043293CPCCPC-2512-S2394Janoshik2026-Q297.852.4195.2Supplier-supplied0PASS
AX-2026-043292CPCCPC-2512-S2394PeptideMeter2026-Q298.212.34—Supplier-supplied0PASS
AX-2026-043297CPCCPC-2512-S2394PeptideMeter2026-Q297.722.9695.9Supplier-supplied0PASS
AX-2026-043467WXTWXT-2508-T5737Medutest2026-Q197.833.95—Supplier-supplied2MARGINAL
AX-2026-041547QYBQYB-2512-Y6648Janoshik2026-Q198.406.19104.9Supplier-supplied0PASS
AX-2026-043466WXTWXT-2508-T5737Janoshik2026-Q197.743.6197.0Supplier-supplied1MARGINAL