Free T3 Examination Procedure

Purpose of examination: Free T3 estimation from serum or plasma by CMIA technology Method.

Responsibility and Authority:

• Calibration: Technician
• Quality Control: Technician
• Routine operation: Technician
• Overall Monitoring: Quality Manager

Sample Details:

1. Type of Sample: Serum, Plasma
2. Type of container and additives: Plain without any additives
3. Patient Preparation: As per Primary Sample Collection Manual sample_collection_manual
4. Stability: At Room temperature 18°–28°C (64°–82°F) stability ≤ 24 hours
5. Handling and transport: As per Primary Sample collection manual
6. Storage: 24 hours at 2-8° C

Required Equipment: Centrifuge, Auto-Pipette, Disposable Tips, Disposable sample cups, FullyAuto Chemistry Analyzer

Required reagents:

• Microparticles anti-T3 (sheep) coated Microparticles in MES buffer with sheep IgG stabilizers.
• Conjugate T3 acridinium-labeled Conjugate in citrate buffer with NaCl and Triton X-100 stabilizers.
• Multi Assay manual dilution
• Pre trigger solution 1.32% (w/v) hydrogen peroxide.
• Trigger solution 0.35 N sodium hydroxide.
• Wash-buffer phosphate buffered saline solution.

Reagent Handling

1. Remove any air bubbles present in the reagents with a new applicator stick, or allow the reagents to settle at the appropriate storage temperature to allow the bubbles to dissipate. To minimize volume depletion, do not use a transfer pipette to remove bubbles
2. Reagent Storage and stability
3. Unopened reagent stable at 15-30°C until expiration date.
4. On board System temperature reagent is stable for 28 days
5. Instability or deterioration should be suspected if there are precipitates, visible signs of leakage or
6. contamination, turbidity, or if calibration or controls do not meet the appropriate criteria.

Calibration Procedure:

• ARCHITECT Free T3 Calibrators
• Frequency:

1. Reagent lot change
2. QC out of range
3. After service or maintenance
4. Replacement in any parts of Instrument

Procedure:

1. Start the equipment.WDI abbotte fully.docx
2. Calibrators are ready to use.
3. Put calibrator 15-20 minutes at room temperature
4. Prior to use, mix the contents by inverting the vial. Do not shake the vial to prevent foam formation.
5. Take a 150 µl calibrator solution in to separate aliquots.
6. Go to the calibration and give the calibration order.
7. Verify calibration with at least two levels of controls
8. If control results fall outside acceptable ranges,root cause analysis or recalibration may be necessary.

Quality control Procedure:

• Name: Bio Rad Level 1 ,2 & 3
• Frequency: As per Quality Control Procedure
• Procedure for Reconstitution of IQC

1. Reconstitution of QC material with 5 ml Distilled water by using calibrated fixed volume pipette.
2. Leave to stand for 30 min in the dark place.
3. Swirl gently several times during the reconstitution period to ensure that the contents are completely dissolved.
4. Prior to use, mix the contents by inverting the vial. Do not shake the vial as the information of foam should be avoided. Ensure that no lyophilized material remains un-reconstituted.
5. Prepare aliquots of 150 µl from the reconstituted QC material.
6. Store these aliquots at -15° C to -20° C.
7. Prior to use, make sure that aliquots should be at room temperature for at least 15 min.

Procedure to run IQC

• Press Control order
• Select Assay /Panel, to be run.
• Select the control/s and its level/s
• Give Carrier Number and Position number
• Press F3 / Add order
• Put respected carrier in RSH rack
• Check IQC results, in case outliers call residents.

Principle of the procedure used for examinations:

1. Sample and anti-T3 coated paramagnetic microparticles are combined. Free T3 (unbound) present in the sample binds to the anti-T3 coated microparticles.
2. After washing, T3 acridinium-labeled conjugate is added.
3. Pre-Trigger and Trigger Solutions are then added to the reaction mixture.
4. The resulting chemiluminescent reaction is measured as relative light units (RLUs). There is an inverse relationship between the amount of Free T3 in the sample and the RLUs detected by the ARCHITECT iSystem optics.

Sample Preparation: Required SampleVolume: 150 µl of the sample Temperature: 37° Take 150-200µl of the sample from Primary tube to the secondary aliquot. Write the sample ID on the aliquot.

Procedure to run Patient sample

• Press Patient order
• Select Assay /Panel, to be run.
• Give Carrier Number and Position number
• Press F3 / Add order
• Put respected carrier in RSH rack

Performance Characteristics:

• Linearity: 3 to 3300 U/L
• The limit of detection (LOD):1.07 pg/mL
• The limit of quantification(LOQ): 1.25 pg/mL.*
• Unit: pg/mL.

Normal and critical ranges:

Laboratory Clinical interpretation: Free T3 is a secondary indicator of thyroid status. Although the majority of patients with hyperthyroidism will have free T3 values greater than the upper limit of the euthyroid range, some may have free T3 values which fall within the normal range.

Interference and cross reaction: Free t3 assay demonstrated <10% interference at the levels indicated below:

Potential source of variation: Turn around time (TAT): Routine: 6.0 hours Urgent: 2.0 hours

Recording of observation:

• Software backup
• Machine raw data

Storage & Disposal of waste: Follow storage & discard procedure

Environmental & Safety control: Contact with acids liberates very toxic gas. Dispose of contents / container in accordance with local regulations.

References:

1. Tietz NW, Huang WY, Rauh DF, et al. Laboratory tests in the differential diagnosis of hyperamylasemia. Clin Chem 1986 32(2):301-307
2. 6 Junge W. Troge B, Klein G, et al. Evaluation of a New Assay for Pancreatic Amylase: Performance Characteristics and Estimation of Reference Intervals Clin Biochem 1989,22 109-114
3. Stuttgart/New York Georg Thieme Verlag 1991 354-361. 3 Salt WB II, Schenker S. Amylase its clinical significance: a review ofthe literature [Review] Medicine 1976,55 269-281.
4. 4 Steinberg WM, Goldstein SS, Davies ND, et al. Diagnostic assays in acute pancreatitis [Review]. Ann Intern Med 1985,102.576-580