AssayIndex
Short bioregulator peptides

L-Glutathione (reduced)

GSH · γ-Glu-Cys-Gly · C10H17N3O6S · monoisotopic 307.0838 Da. The index holds 122 assay reports on this compound across 25 batches from 15 suppliers.

122 reports25 batchesmedian 99.00 %index spec 98.5 %
Section 1

Analytical fingerprint

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

Reduced glutathione oxidises to GSSG on contact with air, and the GSH/GSSG ratio is the only number on a glutathione report that matters. The index reports both species and their ratio rather than a single purity figure, and it treats a total-purity claim without a GSSG number as incomplete. Lots that arrive with a broken vacuum seal routinely show 5–15 % GSSG; sealed lots run under 1 %. This is the compound where the index's data most clearly shows a shipping effect: mean GSSG is 3.1 pp higher in lots shipped without a desiccant note than with one.

Molecular formula
C10H17N3O6S
Monoisotopic mass
307.0838Da
Average mass
307.32Da
Residues
3
Nominal retention (RG-2, 30 min)
4.28min
Retention window
0.20min
Counter-ion as usually shipped
none expected
Typical label claims
200 mg · 600 mg · 1500 mg
Analytical difficulty (index scale)
0.90 — straightforward
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.

06246124921873824984 L-Glutathione (reduced)4.28 min · 99.00 % 4.04 same trace · ×200 vertical expansion, baseline-corrected · main peak off-scale reporting threshold 0.05 % area 05101520253035 Retention time (min) Response (mAU)
Figure 1. A representative L-Glutathione (reduced) trace on the index reference method RG-2, constructed from this page's own numbers: the main peak carries the index median purity of 99.00 % area at the nominal retention time of 4.28 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 122 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 99.00% n=122
Interquartile range 0.99pp n=122
Minimum 96.39% n=122
Maximum 99.93% n=122
Pass rate vs spec 77.9% n=122
Median recovery vs claim 97.0% n=63
Median water 7.80% n=122
Median |mass error| 2.5ppm n=102
06121892.093.094.095.096.097.098.099.0100.092.00–92.25 %: 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=096.25–96.50 %: n=196.50–96.75 %: n=096.75–97.00 %: n=097.00–97.25 %: n=097.25–97.50 %: n=497.50–97.75 %: n=597.75–98.00 %: n=398.00–98.25 %: n=1098.25–98.50 %: n=498.50–98.75 %: n=1698.75–99.00 %: n=1899.00–99.25 %: n=1499.25–99.50 %: n=1399.50–99.75 %: n=1399.75–100.00 %: n=21median 99.00 Purity (% area) Reports
Figure 2. Purity distribution across all 122 L-Glutathione (reduced) records. Dashed line is this compound's median (99.00 %); the solid vertical is the index acceptance specification for the short bioregulator peptides class (98.5 %). 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.

96.196.897.598.298.899.5100.2HJHJ: Q1 98.87, median 99.08, Q3 99.35, n=20outlier 97.63n=20FGPFGP: Q1 99.58, median 99.83, Q3 99.92, n=18n=18SSASSA: Q1 98.78, median 98.99, Q3 99.36, n=17n=17BCHBCH: Q1 97.54, median 97.76, Q3 98.06, n=16outlier 96.39n=16SWBSWB: Q1 98.70, median 98.78, Q3 98.94, n=10outlier 98.18outlier 99.79n=10CPCCPC: Q1 98.15, median 98.28, Q3 98.58, n=9n=9HomopeptideHomopeptide: Q1 98.80, median 99.19, Q3 99.66, n=8n=8WWBWWB: Q1 99.26, median 99.72, Q3 99.86, n=7n=7JEEPJEEP: Q1 99.07, median 99.08, Q3 99.52, n=5n=5MKMMKM: Q1 98.53, median 98.58, Q3 98.77, n=4outlier 99.29n=4WXTWXT: Q1 97.56, median 97.73, Q3 97.90, n=2n=2GGPepsGGPeps: Q1 98.61, median 98.76, Q3 98.92, n=2n=2QSCQSC: Q1 99.74, median 99.81, Q3 99.87, n=2n=2 Purity (% area)
Figure 3. L-Glutathione (reduced) 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
glutathione disulfide (GSSG, +305 Da)+0.52+304.98498%0.211.68
S-sulfonate adduct (+80 Da)-0.14+79.95796%0.131.02
γ-Glu-Cys (−57 Da)-0.18-57.02192%0.122.05
cysteinyl-glycine (−129 Da)-0.24-129.04387%0.181.52

Degradation pathways

  • oxidation of the free thiol to GSSG — this is the whole stability story
  • oxidation is rapid in solution at neutral pH and catalysed by trace metals

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

Section 7

Quarterly coverage

QuarterReportsMedian purityRange
2024-Q10n<3—
2024-Q20n<3—
2024-Q32099.8399.25–99.93
2024-Q41n<3—
2025-Q12399.0798.46–99.93
2025-Q2598.6497.81–99.86
2025-Q31797.9096.39–98.99
2025-Q42598.9097.63–99.79
2026-Q11998.9398.02–99.93
2026-Q21099.4498.07–99.93
2026-Q32n<397.39–99.26

Quarter-by-quarter detail →

Section 8

Most recent records

The 25 most recent L-Glutathione (reduced) records of 122.
ReportSupplierLotLabQuarterPurity %Water %Recovery %ProvenanceFlagsResult
AX-2026-043166GL BiochemGLBI-2606-S7722PeptideMeter2026-Q399.268.52107.1Supplier-supplied1MARGINAL
AX-2026-043461WXTWXT-2605-B5313PeptideMeter2026-Q397.396.92102.2Supplier-supplied0FAIL
AX-2026-042932MKMMKM-2511-F2902Janoshik2026-Q298.578.4192.9Supplier-supplied1MARGINAL
AX-2026-043399WXTWXT-2512-P4300PeptideMeter2026-Q298.078.72—Supplier-supplied1FAIL
AX-2026-042337HJHJ-2511-F3082Janoshik2026-Q299.937.58—Supplier-supplied0PASS
AX-2026-042930MKMMKM-2511-F2902Janoshik2026-Q298.427.8297.4Supplier-supplied1FAIL
AX-2026-042336HJHJ-2511-F3082Janoshik2026-Q299.937.34—Supplier-supplied0PASS
AX-2026-042338HJHJ-2511-F3082Kestrel2026-Q299.936.73—Supplier-supplied0PASS
AX-2026-042937MKMMKM-2602-X3845PeptideMeter2026-Q298.598.86—Supplier-supplied0PASS
AX-2026-042335HJHJ-2511-F3082Janoshik2026-Q299.936.47—Laboratory-retained0PASS
AX-2026-042339HJHJ-2511-F3082Janoshik2026-Q299.597.52—Laboratory-retained0PASS
AX-2026-042931MKMMKM-2511-F2902Janoshik2026-Q299.298.88100.4Supplier-supplied1MARGINAL
AX-2026-041233WWBWWB-2602-U1840Janoshik2026-Q199.939.13—Supplier-supplied0PASS
AX-2026-043311CPCCPC-2602-D2535Kestrel2026-Q198.587.71—Supplier-supplied0PASS
AX-2026-041915JEEPJEEP-2510-S3920Medutest2026-Q199.087.80—Laboratory-retained0PASS
AX-2026-043304CPCCPC-2602-D2535Nordanalyt2026-Q198.127.51—Supplier-supplied0FAIL
AX-2026-041917JEEPJEEP-2510-S3920Janoshik2026-Q199.047.5994.8Supplier-supplied0PASS
AX-2026-043309CPCCPC-2602-D2535Medutest2026-Q198.938.32—Supplier-supplied0PASS
AX-2026-041918JEEPJEEP-2510-S3920Medutest2026-Q199.657.47103.2Laboratory-retained0PASS
AX-2026-043306CPCCPC-2602-D2535Medutest2026-Q198.588.00—Supplier-supplied0PASS
AX-2026-041232WWBWWB-2602-U1840Medutest2026-Q199.249.7294.4Supplier-supplied0PASS
AX-2026-041229WWBWWB-2602-U1840Medutest2026-Q199.729.55—Supplier-supplied0PASS
AX-2026-041231WWBWWB-2602-U1840PeptideMeter2026-Q199.289.31—Supplier-supplied0PASS
AX-2026-043303CPCCPC-2602-D2535Janoshik2026-Q198.687.52—Supplier-supplied0PASS
AX-2026-043310CPCCPC-2602-D2535Janoshik2026-Q198.157.85—Supplier-supplied0FAIL