Peptidetesting

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Analysis

Label claim

A label claim is the manufacturer's statement on a product label about the product's identity, concentration, or quantity. Laboratories use the label claim as a benchmark when they compare it with the product's actual measured results in testing and reporting.

Also called: label claims

Label claim is the stated target or benchmark used by laboratories to evaluate a product's quality against measured lab results. It serves as the declared reference point for assessing identity, strength, and purity, rather than being a measurement itself. Understanding this distinction is crucial for interpreting lab reports and verifying product quality.

Label claim is the benchmark used in a COA

In a Certificate of Analysis (COA), laboratories compare measured results for potency, purity, or identity directly against the label claim. This comparison, often called the 'percentage label claim', indicates how accurately the product matches its stated values. For buyers of research chemicals and peptides, this document is often the primary proof of quality.

To interpret a report correctly, you must know how the claim was tested. For instance, a '>98% purity' claim usually refers to chromatographic purity, which measures the ratio of the target peptide to detectable impurities within the sample.

Main interpretation risks

  • Chromatographic purity does not prove absolute peptide content; a vial can show 98% purity but still be under-filled with the actual substance.
  • Analytical label claims in lab testing quantify chemical dosage, which differs from marketing or health claims like 'High Potency' found on dietary supplements.
  • The label claim is distinct from dosage uniformity, which measures whether the physical weight of individual units in a batch remains consistent.

Sources

  1. [PDF] Analytical Procedures and Methods Validation for Drugs and Biologics
  2. FDA Label Claims: Definitions and Compliance Considerations - Eurofins USA
  3. FDA Sets Peptide Impurity Thresholds as Low as 0.10%, Oath Research Analysis Finds
  5. Small Entity Compliance Guide: Nutrient Content Claims Definition for “High Potency” and Definition for “Antioxidant” for Use in Nutrient Content Claims for Dietary Supplements and Conventional Foods | FDA
  6. Label Statements and Perceived Health Benefits of Dietary Supplements
  7. [PDF] ICH guideline Q14 on analytical procedure development
  8. Peptide purity standards: HPLC, mass spec, and what >98% really means | Compound Review
  9. Label Claims | FACIT.org, FACITtrans
  10. [PDF] Validation of analytical procedures: Text and Methodology Q2 (R1)
  11. What is Analytical Testing?
  13. Guidance for Industry
  14. Peptide Purity: Proven Guide to Reading a COA 2026
  15. How to Read a Peptide COA: Verification Checklist (2026) | PepPal
  16. Identity Testing (ID) – Raw Material Verification
  17. [PDF] 〈905〉 UNIFORMITY OF DOSAGE UNITS - USP
  18. FAQs: <905> Uniformity of Dosage Units - USP