Biologics - Glossary - peptidetesting.cc

Biologics are complex medicinal products derived from natural sources, including human, animal, or microbial sources. This makes them different from chemically synthesized small-molecule drugs. Examples include vaccines, blood components, gene therapies, and recombinant proteins. Under FDA regulations, a protein is defined as a biologic if it contains more than 40 amino acids, while peptides with 40 or fewer amino acids are regulated as standard drugs.

Specialized testing verifies the identity and potency of biologics

Biologics need specialized analytical testing because a high purity percentage does not prove that the molecule is correct or biologically active. These products can vary naturally, and their impurity profiles depend strongly on the manufacturing process.

Laboratories use methods such as mass spectrometry and LC-MS peptide mapping to check the exact amino acid sequence and confirm identity. Bioassays measure potency, meaning whether the biologic works as intended. This matters because even a 99% pure sample could be ineffective if its structure is wrong or it lacks biological activity.

Common interpretation risks for biologic test results

Purity, identity, and potency are separate CoA metrics: purity describes the absence of contaminants, identity confirms the correct substance, and potency measures functional effectiveness.
A CoA that labels a short peptide of 40 or fewer amino acids as "biologic-grade" is often an unjustified claim, because these substances are regulated as standard drugs.
Confusing biologics, biosimilars, and generic drugs can lead to misread laboratory test results.

Specialized testing verifies the identity and potency of biologics

Common interpretation risks for biologic test results

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