by Robert Janetschek, MSc, MT(ASCP)
Considering the varied, and often critical biochemical roles that enzymes play in human pathology and physiology, it is not surprising that their analysis includes some of the most frequently performed tests within the laboratory. As such, it is vital for the laboratory to have access to a supply of clinical reference materials that are primarily focused on enzyme components. For purposes here, such materials are designed and utilized for the calibration verification of instrument systems, as well as for the validation testing of new clinical assays, instrumentation, and a host of other medically oriented products. Access to independent validation tools such as these are vital for the determination of an enzyme method’s overall accuracy, linearity, sensitivity, measurement range and other performance characteristics, as required under a number of current regulatory mandates.
Based upon the input, recommendations and suggestions obtained directly from laboratorians in routine clinical and research-oriented facilities, as well as regulatory agencies, it is desirable that these enzyme verification materials contain the following product attributes and the primary reasons why:
- Liquid Stable & Protein-Based Matrix: A liquid stable, protein-based format not only helps to eliminate reconstitution errors, but also eliminates matrix variations commonly experienced with lyophilized and serum-based products.
- Multi-Level/Analyte Format: A product format such as this helps save time, money, and expenses with numerous departments within a facility.
- Stability Claims: As these materials are not used daily, it is important to have products which have extended shelf-life and open vial stability claims, but also feature multiple freeze/thaw events as well.
- Packaging: With laboratory storage space in demand, it is advantageous that such products are packaged in ergonomically designed kits for convenient storage. Materials filled in dropper vials not only facilitate ease of use, but also minimize product deterioration. Ideally, product should contain fill volumes ample enough to cover multiple testing events and any unexpected system trouble-shooting necessities.
- Customer Support & Product Documentation: In today’s regulatory environment, it is important to select vendors whose product(s) have the necessary FDA 510(k) clearance, when applicable, but is also able to supply various product support documentation (i.e., Instructions For Use, Safety Data Sheets, Value Assignment Sheets, etc.) quickly upon request. Aside from product alone, investigate what ancillary services are available from vendors to further support product and assist the laboratory, including but not limited to, data reduction services, test report generation and printing, on-line and phone support, and the like.
- Product Design Format: For clinical reference materials such as these, it is vital that product formulations incorporate critical blends of specific biologicals, along with highly purified raw material components, to produce bio-based materials that minimize matrix variations. In addition, they should also incorporate the necessary target concentration designs to address the current regulatory requirements for calibration verification materials. As an example, product formulation should include at least one set point for each enzyme within the normal range.
As an example, VERICHEM Laboratories offers materials that are comprised of six separate levels covering a total of 54 individual enzyme activity levels containing the enzyme components Amylase, ALT, ALP, AST, Cholinesterase, CK, GGT, LD, and Lipase. The protein-based matrix is liquid stable and preserved with a proprietary blend of non-reactive materials resulting in an exceptional shelf life and open vial stability claim of 18-months from date of manufacture. The materials also feature universal system compatibility and assay values for many instrument systems, including those from Abbott, Beckman Coulter, and Roche.
About the author
Robert Janetschek, MSc, MT(ASCP), is an experienced veteran of the clinical laboratory industry, with over 40 years of relevant experience. Aside from his direct clinical involvement, he has also held Marketing, Business Development, and Technical leadership positions with several in–vitro diagnostics organizations. Janetschek is currently affiliated with Verichem Laboratories Inc., an industry-recognized leader in the field of clinical reference materials and calibration verification testing, as their Director of Business Development.