Secondary Standards for Pharmaceutical Quality Control

Our secondary standards have multi-traceability to the USP, EP and BP primary standards; in addition, they are manufactured according to ISO/IEC 17025 and ISO Guide 34.
The FDA, USP and EP all recognize the use of secondary standards or working standards that are established with reference to the corresponding primary standard. See specifics for Regulatory Recognition of Secondary Standards.

Search Pharmaceutical Secondary Standards




Products & Ordering Information

Our portfolio of pharmaceutical secondary standards continues to expand as we develop and add new products. Our web catalog will always contain the most up-to-date list of available products.



Features & Benefits

The important product features are:

  • Traceability to United States Pharmacopeia (USP); also to European Pharmacopoeia (EP) and British Pharmacopoeia (BP), if available
  • Analysis performed on instruments validated according to GMP using pharmacopeia monograph methods
  • Certified value according to ISO Guide 34 and ISO 17025 using mass balance approach
  • Comprehensive certificate according to ISO Guide 31


The main benefit is:

  • Eliminate time and effort involved with preparing and validating your own working standards



Comprehensive Certification

The values on the certificate are always traceable to the current pharmacopeia lots.
Note: If a valid pharmacopeia lot changes, then the corresponding secondary standard will be recertified with traceability to the new lot and a new certificate will be made available online.
For this reason, the certificate always needs to be downloaded from the website prior to use of the material!

The certificate contains the following data:

  • Traceability assay results versus pharmacopeia primary standards
  • Value by mass balance (according to ISO 17025)
  • Handling and storage instructions
  • Analytical data


An excerpt of the certificate is shown in the image below, highlighting some of the key information that is displayed.

Traceability Assay Results

Monthly Pharma Secondary Standards COA updates:
Customers are notified in advance of any COA changes that may occur due to re-qualification etc.
This service helps users ensure that they always have the most current version of a product certificate.
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Regulatory Recognition of Secondary Standards

(1) Human Drug CGMP Notes, Vol 9, Number 3, 2001 (Internal FDA Publication):

Q: Can a company use reference standards from sources other than the USP?

A: Yes. Using a source other than USP can be acceptable provided the reference standard incorporates the critical characteristic properties, is suitable for the intended purpose, and is supported by complete documentation…..The supplier’s certificate of analysis should report results of testing to adequately characterize the material across a complete range of quality characteristics.

(2) FDA: Guidance for Industry; Analytical Procedures and Methods Validation, August 2000:

“A reference standard (i.e., primary standard) may be obtained from the USP/NF or other official sources (e.g., CBER, 21 CFR 610.0). A working standard (i.e., in-house or secondary standard) is a standard that is qualified against and used instead of the reference standard.”

(3) United States Pharmacopeia, General Chapter <1010>:

“Use of Reference Standards: Where the use of USP Reference Standards is specified, the USP Reference Standard, or a secondary standard traceable to the USP Reference Standard, is used.”

(4) European Pharmacopoeia, Chapter 5.12:

“Secondary standard: A standard established by comparison with a primary standard. A secondary standard may be used for routine quality control purposes for any of the uses described above for primary standards provided that it is established with reference to the primary standard.”