# Presentation: 077596

## Measurements and Standards for Clinical Diagnostic Markers

**Michael J. Welch**
**Analytical Chemistry Division**
**Chemical Science and Technology Laboratory**
**National Institute of Standards and Technology**

## Measurements and Standards for Clinical Diagnostics

_**Major Deliverables**_

**Standards for the Clinical Diagnostic Community**
- “Higher Order” Reference Methods
- Standard Reference Materials
- Interactive Measurement QA Programs
**Biomarker Validation Program **
**Micronutrients in Blood **
**To Facilitate:**
- Improved Measurement Accuracy and Medical Decision-Making
- Reduced Healthcare Costs
- International Trade Traceability to “standards of higher order”

## Purpose/objective: 	
To Develop and Maintain the Measurements and Standards Infrastructure to Facilitate Accurate Decision-Making Regarding the Diagnosis, Treatment, and Prevention of Diseases

Current Activity Areas: 

Blood Gases
Electrolytes
Enzymes
Hormones
Metabolites and Substrates
Non-Electrolyte Metals
Nucleic Acids
Proteins
pH
Therapeutic and Drugs of Abuse
Vitamins	

Microarrays

**To**** ****Develop and Maintain the Measurements and Standards Infrastructure to Facilitate Accurate Decision-Making Regarding the Diagnosis, Treatment, and Prevention of Diseases**
**Current Activity Areas: **
**Blood Gases**
**Electrolytes**
**Enzymes**
**Hormones**
**Metabolites and Substrates**
**Non-Electrolyte Metals**
**Nucleic Acids**
**Proteins**
**pH**
**Therapeutic and Drugs of Abuse**
**Vitamins****	**
**Microarrays**

**Measurements and Standards for Clinical Diagnostics**

## Slide 4

## Slide 5

## Slide 6

## NIST Role in National Reference System

**for Clinical Measurements**

**Maintain existing Definitive Methods and SRMs**
**Develop new reference methods and SRMs of “higher metrological order” to meet new needs**
**Work with other NMIs to establish equivalence of measurement services**
**Participate in global reference laboratory network and provide reference laboratory measurement services to IVD industry**

## Slide 8

## Slide 9

## Troponin I

***PROBLEM:***
**Troponin I is a complex, heterogeneous**
**protein that may be free or may be**
**complexed with Troponin C and/or **
**Troponin T.**
**Different assay antibodies do not **
**recognize the same form.**

***Project Highlights***
**Completed two round-robins with **
**the AACC that identified the best **
**material for use as a calibrant to **
**harmonize results**
**Material identified is a CIT complex **
**from human heart.  Concentration **
**will be certified at NIST.**
**Future plans are to develop a reference**
** ****method and SRM  for troponin I in blood**

**Troponin I**

## Slide 11

## Slide 12

## SRMs for Flow Cytometry

** ****-  Certified for concentration and purity**
**  ****- Used for fluorometer calibration**
**  ****- Enables a NIST-traceable MESF fluorescence**
**    ****intensity scale to be established**
-     **(MESF = molecules of equivalent soluble fluorophore)**
-   SRM 1933 Fluorescein-Labeled Microbead Suspension
-     (*under   development)*
**  ****-  To be used for flow cytometer calibration (MESF intensity)**
**  ****-  Will help meet the growing need for quantifying analyte per cell levels**

**SRMs for Flow Cytometry**

## Slide 14

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