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.

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.

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 USP or NF tests or assays call for the use of a USP Reference Standard, only those results obtained using the specified USP Reference Standard are conclusive for purposes of demonstrating conformance to such USP or NF standards. While USP standards apply at all times in the life of an article from production to expiration, USP does not specify when testing must be done, or any frequency of testing. Accordingly, users of USP and NF apply a range of strategies and practices to assure articles achieve and maintain conformance with compendial requirements, including when and if tested. Such strategies and practices can include the use of secondary standards traceable to the USP Reference Standard, to supplement or support any testing undertaken for the purpose of conclusively demonstrating conformance to applicable compendial standards. Because the assignment of a value to a standard is one of the most important factors that influences the accuracy of an analysis, it is critical that this be done correctly.”

(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.”

Social Media

LinkedIn icon
Twitter icon
Facebook Icon
Instagram Icon


Research. Development. Production.

We are a leading supplier to the global Life Science industry with solutions and services for research, biotechnology development and production, and pharmaceutical drug therapy development and production.

© 2021 Merck KGaA, Darmstadt, Germany and/or its affiliates. All Rights Reserved.

Reproduction of any materials from the site is strictly forbidden without permission.