• high quality

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  developed for the WHO Collaborating Centre in London

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  performs well in national EQA Scheme

• high performance

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  detection limit 0.1 mIU/L WHO IRP 80/558

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  between-assay CV better than 10% in range 1 - 50 mIU/L

• low cost

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  all reagents are provided - only test tubes and water are required

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  uses inexpensive, robust equipment

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  each kit is sufficient for 100 assay tubes

• convenient

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  magnetic separation

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  shelf life of 1 year at 4-8°C

For information and prices please contact us.

The assay is an immunometric ('sandwich') EIA for the quantitative measurement of TSH in human serum or plasma. TSH in the sample is bound by 2 monoclonal anti-TSH antibodies directed at different epitopes. One antibody is attached to magnetic particles and the other is labelled with alkaline phosphatase. The assay has four main stages:

• Magnetic anti-TSH is incubated with sample (100 µL) for 15 minutes at 37°C followed by a magnetic wash step.
• The magnetic particles are incubated with alkaline phophatase labelled anti-TSH for 1 hour at 37°C followed by 2 magnetic wash steps.
• A coloured enzyme substrate is incubated with the particles I hour at 37°C. The presence of alkaline phosphatase causes a colour change from yellow to pink. The reaction is terminated by addition of Stop Buffer.
• The tubes are then placed in the spectrophotometer or colorimeter. The optical density (at 550nm or 492nm) of each tube can be measured and the results calculated using a data processing program.

Incubation times	15 mins + 1 hr + 1 hr
Standard Range	0-60 mIU/L Standardised against WHO IRP 80/558
Normal Ranges	Adult 0.47-3.78 |mIU/L
Detection Limit	0.1   mIU/L
Assay Reproducibility	Within-batch ±1SD mIU/L %CV 1.2±0.04 3.4 2.5±0.1 3.2 7.6±0.2 2.7 15.7±0.3 1.9
Assay Reproducibility	Between-batch ±1SD mIU/L %CV 1.4±0.1 9.0 2.6±0.1 4.7 7.3±0.6 7.7 15.8±1.8 11.7

TSH EIA Standards - see (*) TSH EIA Magnetic Antibody TSH EIA Enzyme Labelled Antibody TSH EIA Assay Buffer TSH EIA Wash Buffer

EIA Substrate Reagent EIA Substrate Buffer EIA Stop Buffer EIA Internal QC Sample Instruction booklet

(*) calibrated against WHO IRP 80/558.

Test tubes, pipettes, multivortex mixer, magnetic separator, 37°C water-bath and a colorimeter or spectrophometer.