GradeBio Sheet G‑03.05  /  Glutathione, specification G‑03.05Rev. A
GradeBio Entry 05 · specification
Sheet G‑03.05
Revision A  ·  31 Aug 2026

Glutathione.
The whole question
is how much
is still reduced.

A tripeptide supplied as a sterile solution at 200 milligrams to the millilitre. Because it is filled as a liquid rather than a cake, the attribute that matters most is not purity at synthesis but how much of the material is still in the reduced form when the vial is opened.

So the specification carries a separate line for the oxidized dimer, tested at release and again through stability. Same sheet, same table, a different set of numbers, because a solution fails differently from a powder.

CAS
70-18-8
Molecular formula
C10H17N3O6S
Average mass
307.32 g/mol
Form
Solution, aqueous
Assay floor
≥ 99.0 % of label
Presentation
200 mg/mL, 10 mL fill
Label class
P  ·  physician use, prescription
Structure  L‑γ‑glutamyl‑L‑cysteinyl‑glycine  ·  γ‑Glu‑Cys‑Gly
Glutathione, a clear solution in a sealed glass vial.
Plate 2   Entry 05 as filled. A 10 mL solution fill, sealed, specimen photography.

Grade Bio  /  Register  /  Entry 05  /  Sheet G‑03.05

1.0

What this is

Identity and presentation

Reduced glutathione is a tripeptide, and the bond that makes it unusual is the one at the glutamate end: a gamma linkage through the side chain rather than the alpha carboxyl.

That gamma bond is why the molecule resists ordinary peptidases, and it is also why the identity test is a chromatographic comparison against a reference rather than a residue count. Two tripeptides can share a formula and a mass and not share that linkage.

The free thiol at the cysteine is the reactive part. It oxidizes to the disulfide dimer, GSSG, in the presence of air and metal ions, which is why the fill is sealed under nitrogen and why the oxidized fraction has a line of its own in table 2.1.

Class P labelThe vial and its carton carry FOR PHYSICIAN USE ONLY Rx ONLY and the prescription legend. No pharmacy name is printed on the label: dispensing runs through more than one licensed partner, and the pharmacy of record is disclosed at the point of dispensing, not printed in advance.
Not on this sheetNo dose, no schedule, no route, no protocol and no preparation direction. Those are clinical decisions and they belong to the prescriber and the dispensing pharmacist, not to the company that made the material.
2.0

Specification

Released against the figures below, lot by lot

Every attribute has a method behind it and a number the lot has to reach before it leaves. The result column shows specimen lot L‑24417. A lot that misses a single line is not released, and the register entry is marked rather than the sheet edited.

AttributeMethodSpecificationResult
AppearanceVisualClear, colorless to pale yellowConforms
Identity, retentionRP‑HPLC vs referenceConformsConforms
Identity, structureATR‑FTIRConforms to referenceConforms
Assay, reduced glutathioneRP‑HPLC≥ 99.0 % of label99.6 %
Oxidized glutathione, GSSGRP‑HPLC, area %≤ 1.0 %0.18 %
Related substances, totalRP‑HPLC, area %≤ 1.0 %0.31 %
pHPotentiometric, 25 °C4.5 to 6.55.4
OsmolalityFreezing point depressionReport result712 mOsm/kg
Elemental impuritiesICP‑MSPer ICH Q3DConforms
Particulate matterLight obscurationPer USP <788>Conforms
Bacterial endotoxinLAL, kinetic chromogenic≤ 0.5 EU/mg< 0.05 EU/mg
SterilityMembrane filtration, 14 daySterileSterile
Container closure integrityDye ingressNo ingressConforms
Fill volumeGravimetric≥ 10.0 mL10.3 mL
Table 2.1   Glutathione, reduced · specification and specimen result, lot L‑24417.
3.0

Storage and retention

How it is held, and how long the paperwork lives
Storage
2 to 8 °C
Light
Protect from light
Headspace
Filled and sealed under nitrogen
Retest period
12 months from release
Retained sample
24 months, same condition
Retained sampleA sample of every lot is held under the storage condition above for the full retention period, so a question asked in month twenty two can be answered from the material itself rather than from memory.
Why the retest period is shorterA solution has nowhere to hide. The oxidized fraction climbs slowly even sealed and cold, so this entry carries a twelve month retest period against the twenty four months a lyophilized entry carries. The stability summary is on file as GB‑118.
4.0

Documents behind this lot

What an account can pull
DocumentNo.What it shows
Certificate of analysisGB‑101Every attribute in table 2.1, the method, the specification and the measured result, signed on release.
Identity data packageGB‑104The reference chromatogram and the infrared spectrum the lot was compared against, with the GSSG peak identified and integrated.
Method summaryGB‑110The analytical methods named in table 2.1, with their validation state.
Stability summaryGB‑118The data the storage condition and the retest period rest on.
Lot genealogyGB‑140Raw material lot, fill date, container closure lot, and the release signature.
Table 4.1   A verified account can pull all five against any lot it holds.
5.0

How it reaches a patient

The pharmacy of record does the dispensing

Grade Bio does not dispense and does not ship to a patient. Material is supplied only pursuant to a valid prescription for an individually identified patient, and it is dispensed by the licensed pharmacy of record named on the account. The practitioner writes the prescription. The pharmacy fills it. We supply the material and the paperwork that proves what it is. Sheet G‑07 sets out the whole route.

GradeBio

Grade Bio is a brand of Mountain Brands LLC. Entity formation is pending and no registration has been filed. Correspondence to jv@gradebio.com or sw@gradebio.com.

Pre‑launch document Entity pending

The register

The company