V8 Peptides — Engineered Performance

Research Library

Peptide Research, Explained

Evergreen guides on purity, documentation, handling, and the compounds themselves — written as research and procurement education. For laboratory research use only.

Tirzepatide Pricing: What Drives the Cost of Research-Grade Material
PricingTirzepatide

Tirzepatide Pricing: What Drives the Cost of Research-Grade Material

A look at chain length, the fatty-diacid modification, verification costs and how to compare tirzepatide prices per milligram of documented peptide.

Read article →
Where to Buy PT-141 (Bremelanotide) for Research
Buying GuidePT-141

Where to Buy PT-141 (Bremelanotide) for Research

A buyer's guide to sourcing PT-141 for laboratory research: purity and identity checks for a cyclic peptide, questions for suppliers, storage and concentration math.

Read article →
MOTS-c Purity Testing: HPLC & Mass-Spec Identity Verification
MOTS-cQuality & Testing

MOTS-c Purity Testing: HPLC & Mass-Spec Identity Verification

Sequence-specific guide to verifying a synthetic MOTS-c lot: methionine oxidation, charge states, chromatogram reading and certificate contents.

Read article →
Cagrilintide Purity Testing: HPLC, Mass Spec & CoA Guide
CagrilintideQuality & Testing

Cagrilintide Purity Testing: HPLC, Mass Spec & CoA Guide

A practical guide to verifying cagrilintide lots: reversed-phase HPLC for a lipidated amylin analog, mass-spec identity at about 4409 Da, and what a credible CoA contains.

Read article →
IGF-1 LR3 Purity Testing: HPLC, Mass Spec & Folding
IGF-1 LR3Quality & Testing

IGF-1 LR3 Purity Testing: HPLC, Mass Spec & Folding

A methods-first guide to verifying IGF-1 LR3: what HPLC, SDS-PAGE and mass spectrometry each prove, why folding is the extra question for this protein, and what a useful COA contains.

Read article →
Semax Purity Testing: HPLC, Mass Spec & CoA Guide
SemaxQuality & Testing

Semax Purity Testing: HPLC, Mass Spec & CoA Guide

How semax lots are verified: reversed-phase HPLC, mass spectrometry near 814 Da, methionine oxidation, proline-isomer quirks, and the documents a complete certificate contains.

Read article →
Selank Purity Testing: HPLC, Mass Spec & CoA Guide
SelankQuality & Testing

Selank Purity Testing: HPLC, Mass Spec & CoA Guide

How selank is verified in the lab: HPLC for purity, mass spectrometry to confirm the Pro-Gly-Pro extension, proline-related impurities and what a lot CoA should contain.

Read article →
PT-141 Purity Testing: HPLC and Mass Spec Identity Verification
PT-141Quality & Testing

PT-141 Purity Testing: HPLC and Mass Spec Identity Verification

A cyclic peptide one dalton from its parent needs more than a purity number. How HPLC, mass spectrometry and a good CoA verify PT-141.

Read article →
Melanotan-II: Purity Testing & Identity Verification
Melanotan-IIQuality & Testing

Melanotan-II: Purity Testing & Identity Verification

How HPLC and mass spectrometry verify melanotan-II, including cyclization state, oxidation and dimer impurities, and the documents a lot should carry.

Read article →
KPV Purity Testing: HPLC, Mass Spec & CoA Guide
KPVQuality & Testing

KPV Purity Testing: HPLC, Mass Spec & CoA Guide

A practical guide to verifying KPV lots: why a tripeptide is hard to chromatograph, what the ~342 Da mass check shows, and how to read a KPV certificate of analysis.

Read article →
KLOW Stack Purity Testing: Verifying Four Peptides in One Vial
KLOW StackQuality & Testing

KLOW Stack Purity Testing: Verifying Four Peptides in One Vial

Why a blend needs component-level testing, what each analytical method shows for GHK-Cu, KPV, BPC-157 and TB-500, and how to read a KLOW Stack certificate.

Read article →
GHK-KPV Purity Testing: HPLC, Mass Spec & Identity Verification
GHK-KPVQuality & Testing

GHK-KPV Purity Testing: HPLC, Mass Spec & Identity Verification

How HPLC and mass spectrometry verify GHK-KPV: reference masses, joined chain versus blend, chromatogram checks and what a certificate should contain.

Read article →
AOD-9604 Purity Testing: HPLC, Mass Spec & CoA Guide
AOD-9604Quality & Testing

AOD-9604 Purity Testing: HPLC, Mass Spec & CoA Guide

A working guide to verifying an AOD-9604 lot: reversed-phase HPLC, mass spectrometry for fragment boundary and disulfide state, net peptide content, and the documents a complete CoA contains.

Read article →
Hexarelin Purity Testing: HPLC, Mass Spec & CoA Guide
HexarelinQuality & Testing

Hexarelin Purity Testing: HPLC, Mass Spec & CoA Guide

How hexarelin is verified in the lab: reversed-phase HPLC, mass-spectrometric identity, the difference between purity and content, and what a lot-specific CoA should contain.

Read article →
Tesamorelin: Purity Testing & Identity Verification
TesamorelinQuality & Testing

Tesamorelin: Purity Testing & Identity Verification

How HPLC and mass spectrometry verify tesamorelin, why the N-terminal hexenoyl group is the key identity check, and what a lot certificate should contain.

Read article →
CJC-1295 (DAC): Purity Testing & Identity Verification
CJC-1295 DACQuality & Testing

CJC-1295 (DAC): Purity Testing & Identity Verification

How HPLC and mass spectrometry verify CJC-1295 with DAC, why maleimide hydrolysis matters, and what a lot-specific certificate should show.

Read article →
CJC-1295 (No DAC) Purity Testing: HPLC, Mass Spec & CoA Guide
CJC-1295 No DACQuality & Testing

CJC-1295 (No DAC) Purity Testing: HPLC, Mass Spec & CoA Guide

A practical guide to verifying a CJC-1295 (No DAC) lot: reading the HPLC trace, confirming the ~3,368 Da mass, and what a certificate should contain.

Read article →
Ipamorelin Purity Testing: HPLC, Mass Spec & CoA Guide
IpamorelinQuality & Testing

Ipamorelin Purity Testing: HPLC, Mass Spec & CoA Guide

How ipamorelin lots are verified: reversed-phase HPLC, mass-spec identity near 712 Da, what the method cannot see, and the documents a complete certificate includes.

Read article →
Sermorelin Purity Testing: HPLC, Mass Spec and COA Guide
SermorelinQuality & Testing

Sermorelin Purity Testing: HPLC, Mass Spec and COA Guide

What HPLC and mass spectrometry each prove for sermorelin, which mass shifts signal oxidation or deamidation, and what a batch COA should contain.

Read article →
NAD+ Purity Testing: HPLC, Identity & Degradation Checks
NAD+Quality & Testing

NAD+ Purity Testing: HPLC, Identity & Degradation Checks

NAD+ is a small polar dinucleotide, so its purity testing differs from peptides. This guide covers HPLC, mass identity, degradation products and CoA checks.

Read article →
CJC-1295 & Ipamorelin Purity Testing: How to Verify a Blend
CJC-1295 & IpamorelinQuality & Testing

CJC-1295 & Ipamorelin Purity Testing: How to Verify a Blend

A two-peptide blend needs more than one purity number. This guide covers per-component HPLC, mass-spec identity, molar ratio, COA contents and the limits of testing.

Read article →
GHK-Cu Purity Testing: Sequence, Copper Content and Coordination
GHK-CuQuality & Testing

GHK-Cu Purity Testing: Sequence, Copper Content and Coordination

GHK-Cu needs two kinds of testing: sequence purity for the tripeptide and copper content and coordination for the metal. Here is how each is measured and read.

Read article →
BPC-157 Purity Testing: HPLC, Mass Spec and COA Explained
BPC-157Quality & Testing

BPC-157 Purity Testing: HPLC, Mass Spec and COA Explained

A researcher's guide to verifying a BPC-157 lot: what HPLC and mass spectrometry each prove, which impurities each can miss, and what a batch COA should show.

Read article →
TB-500 Purity Testing: HPLC, Mass Spec & CoA Guide
TB-500Quality & Testing

TB-500 Purity Testing: HPLC, Mass Spec & CoA Guide

A practical guide to verifying TB-500 lots: what the name refers to, how HPLC and mass spectrometry work together, and what a credible certificate of analysis shows.

Read article →

33 articles in Quality & Testing