Skip to main content
Nexphoria

Research Tools

Purity Checker & COA Guide

Look up typical HPLC purity specifications for 28+ research compounds. Learn to read a Certificate of Analysis, know what a good COA looks like, and spot the red flags that signal fraudulent or low-quality product.

Compound Purity Specifications

Typical HPLC purity ranges from published research-grade specifications. Select a compound for full details.

CompoundMin HPLCTypical
BPC-15798%99.2%
TB-500 (Thymosin Beta-4)98%99%
GHK-Cu98%99.5%
AOD-960498%99.1%
KPV98%99.6%
Sermorelin98%98.8%
Tesamorelin98%99%
CJC-1295 No DAC (Mod GRF 1-29)98%99.2%
Ipamorelin98%99.4%
MK-677 (Ibutamoren)99%99.7%
Hexarelin98%98.9%
Semaglutide98%99.1%
Tirzepatide98%98.7%
Retatrutide98%98.5%
MOTS-c98%99%
Semax98%99.3%
Selank98%99.2%
DSIP98%98.5%
PT-141 (Bremelanotide)98%99%
Kisspeptin-1098%98.8%
Oxytocin99%99.5%
Epitalon98%99.4%
NAD+99%99.7%
SS-31 (Elamipretide)98%99.1%
GHK-Cu (Copper Peptide)98%99.5%
Thymosin Alpha-1 (Tα1)98%99%
LL-3798%98.5%
Snap-8 (Acetyl Octapeptide-3)98%99.2%
Melanotan 298%99%

How to Read a Certificate of Analysis

A COA is only as good as the lab that generated it. Here's what every section should contain and what to verify.

Header & Identity

  • Compound name (IUPAC or common)
  • CAS number
  • Molecular formula
  • Molecular weight (exact, not rounded)
  • Lot/batch number (must match vial label)
  • Analysis date
  • Issuing laboratory name, address, accreditation

HPLC Purity

  • Measured purity value with decimal (e.g., 99.2%)
  • Column type and dimensions
  • Mobile phase A and B composition
  • Gradient program
  • Detection wavelength (nm)
  • Flow rate (mL/min)
  • Chromatogram image with peak labels and area %

Mass Spectrometry

  • Method: ESI-MS, MALDI-TOF, or LC-MS
  • Observed [M+H]+ or multi-charge envelope
  • Theoretical MW for comparison
  • Ion mode (positive/negative)

Additional QC Tests

  • Karl Fischer water content (important for lyophilized peptides)
  • Residual solvents (TFA, acetonitrile, acetic acid)
  • Appearance (white/off-white lyophilized powder)
  • Endotoxin / LAL (for injectable-grade compounds)
  • pH of reconstituted solution

Conclusion & Sign-Off

  • Pass/Fail statement against specification
  • Analyst name or ID
  • QA signatory
  • Statement that compound meets stated specification

COA Red Flags

These are the warning signs that a COA was fabricated, recycled from another batch, or generated without actual laboratory analysis.

CRITICAL

No HPLC chromatogram included

A purity number without a chromatogram is unverifiable. Any legitimate COA shows the HPLC trace — peak position, peak area %, baseline, and column/method details.

WARNING

Purity stated as '>99%' with no decimal

Legitimate labs report actual measured values (e.g., 99.2% ± 0.3%). A generic '>99%' often means the purity was never actually measured with instrument data.

CRITICAL

MW or molecular formula doesn't match compound

Cross-check every COA against the compound's known molecular weight. A wrong MW usually indicates the wrong compound, salt form confusion, or a fabricated document.

WARNING

No mass spectrometry confirmation

HPLC measures purity by peak area but can't confirm identity. ESI-MS or MALDI confirms the molecular weight, verifying you have the right compound at that purity.

CRITICAL

Lab name not verifiable (Google search returns nothing)

Any analytical lab issuing COAs should have a web presence, accreditation (ISO 17025 is standard), and contact information. Fictional lab names are a major fraud signal.

CRITICAL

Batch number doesn't match product labeling

The lot number on the vial label must match the COA exactly. Mismatched batch numbers mean the COA was not generated for the product you received.

WARNING

Endotoxin / LAL test missing for injectable-grade

Endotoxin limits matter for injectable research compounds. Legitimate suppliers include LAL (Limulus Amebocyte Lysate) or rFC test results. Absence is acceptable for topical-only compounds.

WARNING

Date of analysis older than 24 months

COAs should reflect recent analysis — not a recycled document from a prior batch. Compounds degrade; a stale COA may not reflect current product quality.

WARNING

HPLC method not specified (column, mobile phase, gradient)

A complete COA specifies: column type and dimensions, mobile phase (A and B), gradient program, detection wavelength, and flow rate. Without this, results are unreproducible and unverifiable.

CRITICAL

Single retention time peak claimed as 99%+ but chromatogram shows multiple peaks

If the annotated purity says 99.2% but the chromatogram clearly shows multiple peaks, the annotation is deceptive. Count the peaks yourself.

Signs of a High-Quality COA

These indicators correlate with genuine laboratory analysis from credentialed facilities.

  • ISO 17025 accredited laboratory with verifiable address
  • HPLC chromatogram shows single sharp peak with tailing factor < 1.5
  • ESI-MS confirms correct [M+H]+ within 0.02% of theoretical MW
  • Karl Fischer water content reported (5–12% typical for acetate salt lyophilizates)
  • LAL endotoxin result < 1 EU/mg (< 0.1 EU/mg for injectable-grade)
  • Batch number printed on vial label matches COA exactly
  • Analysis date within 12 months of purchase date
  • Method details complete: column, mobile phase, gradient, flow rate, detection wavelength
  • Appearance section matches (white/off-white lyophilized powder)
  • Solubility test result included
Research Use Only. The purity specifications listed here are reference values derived from published literature and standard industry practice. They are provided for educational purposes to assist qualified researchers in evaluating supplier documentation. They do not constitute analytical guarantees or regulatory standards. All Nexphoria products are intended for in vitro or preclinical laboratory research only and are not for human use, veterinary use, or consumption.

RUOFor Research Use Only (RUO) — Not for human consumption, clinical use, diagnostic use, or veterinary applications.