For laboratory research use only. Every lot independently tested; certificates published by lot.

A Glutathione research supplier built around testing and transparency.

Buy Glutathione research peptide, with every lot’s COA published

Glutathione Labs is a dedicated Glutathione research supplier with a controlled sourcing and quality-assurance program. Research material is sourced through our qualified manufacturing supply chain and subjected to analytical testing and lot-level documentation before release. Current availability is provided through Klow.bio.

For laboratory research use only. Glutathione Labs does not provide medical advice or usage guidance.

Certificate summary, lot KB9987 Glutathione 600 mg
Purity (HPLC-UV)
99.37%
Identity (LC-MS)
Confirmed
Net content
567.86 mg
Reported
May 20, 2026
From the Freedom Diagnostics certificate, accession 2605190194. Open the full lot record.
99.37%
HPLC-UV purity, current lots
2 of 2
Lots with identity confirmed by LC-MS
94%
Lowest measured net content vs. label, current lots
100%
Lots tested by an independent lab
Full COA
Certificate PDF published for every lot

Glutathione at a glance

The essential facts about Glutathione and Glutathione Labs. Every figure on this page comes from the published certificates of analysis or the product specification.

Product
Glutathione
Type
Tripeptide thiol (reduced glutathione, GSH), 3 residues
Also known as
GSH, Reduced glutathione, γ-L-Glutamyl-L-cysteinylglycine
CAS number
70-18-8
Molecular formula
C10H17N3O6S
Molecular weight
307.32 g/mol (average)
Form
White lyophilized powder
Vial sizes
600 mg
Purity, current lots
99.37% (HPLC-UV)
Purity specification
≥95%
Identity
Confirmed by LC-MS on every lot
Testing laboratory
Freedom Diagnostics (independent)
Current lot
KB9987, reported May 20, 2026
Operated by
Klow Labs LLC, Chicago, IL
Where to order
klow.bio

Last updated

Glutathione research peptide

What is Glutathione?

Glutathione (GSH) is the tripeptide γ-L-glutamyl-L-cysteinylglycine. Unlike an ordinary peptide, its first bond is made through the side-chain (γ) carboxyl of glutamate rather than the backbone carboxyl, which protects it from most peptidases. Its cysteine thiol is the reactive centre: two glutathione molecules can be oxidized to the disulfide GSSG, and the GSH/GSSG pair is the main thiol redox buffer inside cells, which is why glutathione is one of the most widely used reagents in biochemistry and cell biology.

Glutathione Labs supplies reduced glutathione as a lyophilized powder in 600 mg vials. Every lot is tested by an independent laboratory for HPLC-UV purity, LC-MS identity and net content, with the certificate published here before sale through Klow.bio.

Structural features that matter for analysis

The free thiol makes glutathione sensitive to air oxidation, especially in solution, where it slowly converts to the disulfide GSSG (612.6 g/mol). LC-MS distinguishes the two easily. Keeping the powder sealed and dry limits that conversion.

Sizes and ordering

Glutathione is supplied as a white lyophilized powder in 600 mg vials. It is sold through klow.bio, operated by Klow Labs LLC, where current pricing, bundle discounts and shipping options are listed. Orders ship the next business day. Same-day cutoff is 4:00 PM CT, with overnight and 2-day options at checkout.

Glutathione specifications
ProductGlutathione
TypeTripeptide thiol (reduced glutathione, GSH)
Molecular formulaC10H17N3O6S
Molecular weight307.32 g/mol (average)
Length3 residues
Sequenceγ-Glu-Cys-Gly
FormReduced (GSH), free thiol
Linkageγ-Glutamyl bond (Glu side chain to Cys)
CAS number70-18-8
FormWhite lyophilized powder
Vial sizes600 mg
Purity specification≥95% (HPLC-UV)
Purity, current lots99.37%
StorageStore sealed, dry and protected from light at the temperature stated on the vial label. Allow a cold vial to reach room temperature before opening.
DesignationResearch use only

Where to buy Glutathione for research

Glutathione research material from Glutathione Labs is available through klow.bio, the online store of Glutathione Labs’ parent company, Klow Labs LLC. Product information, lot results and the certificate of analysis for every lot are published here on buyglutathionepeptide.com.

Glutathione comes in 600 mg vials, currently priced at $29.99, with bundle pricing (2 vials save 5%; 3 or more vials save 10%). Orders ship the next business day. Same-day cutoff is 4:00 PM CT, with overnight and 2-day options at checkout.

Vial sizeCurrent lotPurity (HPLC-UV)IdentityNet contentEndotoxinCertificateOrder
600 mg KB9987 99.37% Confirmed 567.86 mg Not tested Lot KB9987 Order 600 mg

What Glutathione Labs documents for every Glutathione lot

Glutathione Labs publishes lot-specific analytical documentation for its Glutathione research material. Each item below is published for every lot and can be checked against the laboratory record.

Independent testing

Every lot is tested by Freedom Diagnostics, an independent analytical laboratory. Published results come from the laboratory's certificate, not in-house testing.

The whole certificate, not a number

Every lot's certificate is published as a PDF, with the chromatogram behind the purity figure and the mass spectrum behind the identity result, alongside a readable lot record.

Identity confirmed on every lot

LC-MS separates the sample and measures the mass of the main component, confirming it has the molecular weight expected for the compound. The method is named on every lot record, so it is clear what the result does and does not establish.

Results against specification

Current lots test at 99.37% by HPLC-UV, well above the ≥95% release specification, with net content measured on every lot.

Verifiable at the source

Every certificate carries the laboratory's QR code. You can confirm results directly with the lab instead of taking our copy on trust.

Clear about limits

Lots without endotoxin or microbial testing say "Not tested". Each certificate page explains what the tests do and don't establish.

How to evaluate a Glutathione supplier

The questions worth asking any supplier of Glutathione research material, why each one matters, and how Glutathione Labs answers them.

What to checkWhy it mattersGlutathione Labs
Independent third-party testingResults produced by the seller can't be checked independently.✓ Every lot tested by Freedom Diagnostics
Lot-specific certificatesA generic certificate may not describe the vial you receive.✓ Each COA tied to the lot number on the vial label
Chromatogram availableA purity figure without the trace behind it can't be evaluated.✓ In the certificate PDF for every lot
Separate identity testHPLC purity shows how much of the sample is the main peak, not which compound the peak is.✓ LC-MS on every lot
Measured net contentConfirms how much peptide is actually in the vial.✓ Measured on every lot, reported per lot
Verifiable with the labPrevents altered or reused certificates.✓ Lab QR code on every certificate
Named company and contactAccountability requires a real business you can reach.✓ Klow Labs LLC, Chicago; (708) 262-7687

Current lots and certificates of analysis

Each row is one tested lot. Figures are copied from the laboratory certificate; open a lot to see its full record and download the certificate PDF with its chromatogram and mass spectrum.

LotVial sizeNet contentPurity (HPLC-UV) Identity (LC-MS)Endotoxin (LAL)Microbial (PCR)ReportedCOA
KB9987 600 mg 567.86 mg 99.37% Confirmed Not tested Not tested View lot KB9987
KB9987 600 mg 567.86 mg 99.37% Confirmed Not tested Not tested View lot KB9987

Testing laboratory: Freedom Diagnostics. Release specification: purity ≥95% by HPLC-UV with identity confirmed by LC-MS. Results apply only to the lot listed. Certificates list the testing client as Klow.bio / Klow Labs LLC, the company that operates Glutathione Labs.

Lot-to-lot consistency

Across 2 current lots, HPLC-UV purity ranges from 99.37% to 99.37%, a spread of 0.00 percentage points. Differences of a few tenths of a percent are expected between separately produced and separately tested batches.

Measured net content by lot: 567.86 mg in a 600 mg vial, 567.86 mg in a 600 mg vial.

HPLC-UV purity by lot. The scale runs from 98.0% to 100% so small differences are visible; every lot shown meets the ≥95% release specification.

How identity is confirmed

A purity figure says the sample is homogeneous; it does not say which compound the main peak is. That is answered by a separate identity test: liquid chromatography–mass spectrometry (LC-MS).

LC-MS separates the sample and measures the mass of the main component, confirming it has the molecular weight expected for the compound. Each certificate reports the identity result together with the mass spectrum it is based on.

How each test works and what it can’t show

Current Glutathione lot
ProductGlutathione 600 mg
LotKB9987
Testing laboratoryFreedom Diagnostics
Received / reportedMay 19, 2026 / May 20, 2026
Purity (HPLC-UV)99.37%
Identity (LC-MS)Confirmed
Net content567.86 mg
Endotoxin / PCRNot tested / Not tested
Accession2605190194

Analytical testing on Glutathione

Three methods appear on Glutathione certificates. Each answers a different question, and none answers every question on its own, which is why they are used together.

HPLC-UV purity

Answers: how much of the sample is the main compound?

Reversed-phase high-performance liquid chromatography separates the sample's components by hydrophobicity, and a UV detector records each as a peak. Purity is the main peak's area as a percentage of all detected peak area.

Limits: does not identify the peak, and impurities that co-elute or absorb weakly in UV can be under-counted. More on HPLC

LC-MS identity

Answers: is the main compound Glutathione?

The separated sample enters a mass spectrometer via electrospray ionization, which gives the molecule one or more charges. The observed ions, near m/z 308 (1+) and 155 (2+), are matched against values calculated from Glutathione's molecular weight of 307.32.

Limits: confirms molecular weight, not amino-acid order.

Net content

Answers: how much Glutathione is in the vial?

The laboratory quantifies the main compound in the tested vial against a standard. It is reported in milligrams next to the labeled vial size.

Limits: measured on the vial tested; other vials from the same lot are expected to be similar but are not individually measured.

From lot to published certificate

  1. Lot assignedA lot number is assigned and printed on every vial label.
  2. Sample sentVials from the lot go to Freedom Diagnostics, an independent lab.
  3. AnalysisHPLC-UV purity, LC-MS identity and net content, plus endotoxin and PCR where listed.
  4. ReviewResults are compared with the stated specification: ≥95% purity, identity confirmed.
  5. PublishedThe lot record and certificate PDF are posted at /coa/ under its lot number.
  6. VerifiableAnyone can look the lot up at /verify/ and confirm it with the laboratory.

Full testing methodology

Verify your vial's certificate

You shouldn't have to take a supplier's word for its results. Here's how to check a Glutathione certificate yourself.

  1. Find the lot number on your vial. It is printed on the label, for example KB9987.
  2. Look it up. Enter it at buyglutathionepeptide.com/verify, or open the matching lot in the COA archive.
  3. Check the lab's own record. Scan the Freedom Diagnostics QR code printed on the certificate, then search for klow.bio under the Company tab to view the laboratory record.
  4. Compare the details. Lot number, the laboratory’s reference numbers, purity and dates should match exactly.

What a certificate of analysis does and doesn't show

  • A COA reports the identity, purity and content of the specific sample tested, on its test date. Results apply to that lot only.
  • HPLC purity measures the main peak relative to other detected components. It does not identify the peak on its own; the separate identity test (LC-MS) does that.
  • Mass confirmation matches molecular weight. It does not by itself confirm amino-acid order.
  • Endotoxin and microbial results apply only where those tests appear on the certificate. Lots without them are marked "Not tested".
  • A certificate does not establish stability after the test date or suitability for any particular purpose.

Frequently asked questions about Glutathione

What is Glutathione?

Glutathione is a tripeptide thiol (reduced glutathione, GSH). Glutathione Labs supplies it as a white lyophilized powder in 600 mg vials, with an independent certificate of analysis for every lot.

What is Glutathione research material?

Glutathione research material is Glutathione supplied for laboratory research, sold by lot, with each lot's identity, purity and net content documented by an independent laboratory in a published certificate of analysis.

What is the molecular formula and weight of Glutathione?

The molecular formula is C10H17N3O6S and the average molecular weight is 307.32 g/mol. The peptide has 3 residues.

How is Glutathione analyzed?

Glutathione is analyzed with complementary methods: HPLC-UV for purity, LC-MS for identity, a quantitative measurement for net content, and, where listed, LAL endotoxin and PCR microbial testing. Results are published per lot at buyglutathionepeptide.com/coa/.

Who tests Glutathione?

Every lot is tested by Freedom Diagnostics, an independent third-party analytical laboratory. Glutathione Labs does not test its own material for published certificates.

What purity does Glutathione test at?

Current lots report HPLC-UV purity 99.37%, against a stated release specification of ≥95%. The most recent result is 99.37% for lot KB9987.

What is a Glutathione COA?

A Glutathione certificate of analysis is the testing laboratory's report for one lot: the lot number, test dates, methods and results for purity, identity and net content. Glutathione Labs publishes every lot's COA as a readable page at buyglutathionepeptide.com/coa/.

Where can I find the COA for my vial?

Find the lot number printed on your vial label and enter it at buyglutathionepeptide.com/verify/, or open that lot in the COA archive at buyglutathionepeptide.com/coa/.

How do I confirm a COA with the laboratory?

Scan the Freedom Diagnostics QR code printed on the certificate, then search for klow.bio under the Company tab to view the laboratory record.

Where can I buy Glutathione?

Current Glutathione research material availability is provided through Klow.bio, the purchasing platform operated by Klow Labs: https://klow.bio/product/glutathione/ Lot records, testing information and certificates of analysis are published on buyglutathionepeptide.com so they can be reviewed before purchasing.

Can I order Glutathione?

Yes. Purchasing information and current availability for Glutathione research material are provided through Klow.bio: https://klow.bio/product/glutathione/

Is every Glutathione lot independently tested?

Yes. Every lot is tested by Freedom Diagnostics, an independent laboratory, for HPLC-UV purity, LC-MS identity and net content. The stated release specification is ≥95% HPLC-UV purity with identity confirmed by LC-MS. The current lot, KB9987, reported 99.37% purity.

All questions and answers

About Glutathione Labs

Glutathione Labs is a dedicated Glutathione research supplier with a controlled sourcing and quality-assurance program. Research material is sourced through our qualified manufacturing supply chain and subjected to analytical testing and lot-level documentation before release.

Glutathione Labs operates buyglutathionepeptide.com and supplies one research material, Glutathione, with the analytical record behind every lot. Glutathione Labs is operated by Klow Labs LLC, a Chicago company that also operates klow.bio, where Glutathione is sold.

Our job is narrow on purpose: supply a well-characterized research material and publish the evidence for what is in each vial. We do not provide medical advice, protocols or usage guidance.

About Glutathione Labs, research updates or Contact us

Legal entity
Klow Labs LLC
Address
3838 N Ravenswood Ave PMB 2027, Chicago, IL 60613
Contact
contact@klow.bio
(708) 262-7687
Testing laboratory
Freedom Diagnostics

Buy Glutathione

600 mg vials. Current lot KB9987 tested at 99.37% purity with identity confirmed by LC-MS. Current purchasing is available through Klow.bio.