Thyroid-stimulating hormone(TSH) ELISA Test Kit

INTENDED USE

      Detection Kit for thyroid-stimulating hormone(TSH) (Enzyme-Linked ImmunoSorbent Assay , ELISA).It is used in quantitative tests for thyroid-stimulating hormone(TSH) in human serum.

SUMMARY AND CLINICAL SIGNIFICANCE

Thyroid-stimulating hormone (TSH) secretion is controlled by a negative feedback mechanism in which the variations of circulating thyroid hormone levels interact with the hypothalamic- pituitary axis to adjust TSH production. TSH synthesis and secretion are also stimulated by TRH, a tripeptide produced by the hypothalamus and inhibited by somatostatin. In the normal population, circulating TSH has been found, using this procedure, to be below 4.5 mIU/L under baseline conditions. Investigation of a hyperthyroid population demonstrates an increased frequency of samples whose TSH levels are less than 0.1 mIU/L and at the detection limit. Development of sensitive determinations of TSH has therefore facilitated clinical interpretation of hypothalamic, pituitary and thyroid related desorders. Indeed, elevated levels of T3 and T4 reduce TSH output by the pituitary. However, a single basal serum TSH determination is not considered to be discriminatory as such for the diagnosis of hyperthyroidism, which often requires a dynamic TRH test. On the contrary, the demonstration of an elevated circulating TSH level is a clear indication for the development of primary hypothyroidism in most instances. In such situation, compl- ementary investigation of the pituitary/thyroid axis should be undertaken. Here again, the most useful dynamic test is the TRH stimulation test. In case of simultaneous elevation of both TSH and thyroid hor- mone levels, the diagnosis should be oriented towards a state of thyroid hormone resistance and further documented by stimuli- tion(TRH) and inhibition(T3, T4)tests.

PRINCIPLE

TSH kit uses a “sandwich principle”, Enzyme-linked immunological sorbent assay. To measure TSH levels in serum, plastic wells coated with a monoclonal antibody of TSH are supplied in the kit. After the patient’s specimen and another mono-antibody labelled with HRP are added, TSH, if present, is fixed to the solid phase antibody and creating a HRP-antibody ~TSH~antibody “sandwich”. After TMB substrate added, the result is obtained by EIA plate reader.

MAIN COMPONENTS

Coated Microplate: 1 plate (8×12 wells), Ready to use. Coated with anti-TSH antibody and sealed in an aluminum bag. Remove the strips in the resealable bag with a desiccant to protect from moisture after opened. Store at 2~8℃ until expiration date.

HRP Conjugate: 1 vial of 6ml, Ready to use. Store at 2~8℃ until expiration date.

Calibrator:,7 vials of 1ml, Ready to use. Labeled with S₀ to S₆ and the concentration of TSH is 0,0.3, 0.6, 1.5, 3.0, 6.0, 12.0mIU/L. Store at 2~8℃ until expiration date.

Control: 2 vials of 1ml, Ready to use. Store at 2~8℃ until expiration date. The concentration of low value is 1.51~2.81 mIU/L. The concentration of high value is 4.8~8.92 mIU/L. Store at 2~8℃ until expiration date.

Chromogen A: 1 vial of 7ml, Ready to use. Store at 2~8℃ until expiration date.

Chromogen B: 1 vial of 7ml, Ready to use. Store at 2~8℃ until expiration date.

Stop Solution: 1 vial of 7ml, Ready to use. Store at 2~8℃ until expiration date.

Wash buffer: 1 vial of 15ml, Concentrate 20-fold, diluting with deionized water before the assay. Store at 2~8℃ until expiration date.

Plate sealer: 2 pieces.

Plastic resealable bag: 1 set.

Instruction manual: 1 copy.

SPECIMEN COLLECTION AND PREPARATION

Serum specimens can be tested by the TSH procedure. Remove serum from the clot as soon as possible to avoid hemolysis. Covered specimens can be stored up to 48 hours at 2~8℃.

Specimens held for a longer time can be frozen at –20℃ and avoid repeated freeze melting.

Serum samples with concentrations expected to be greater than 12 mIU/L should be diluted with normal saline.

NOTE: If needed, remove by centrifugation the suspended fibrin particles or aggregates which are liable to produce falsely positive results.

PREPARATIONS

1.Allow all specimens and reagents to reach room temperature and mix thoroughly by gentle inversion before use.

2.Prepare Wash buffer by diluting Wash Concentrate 20-fold with deionized water. The diluted wash solution is stable in room temperature for at least one week

ATTENTIONS

1. Do not exchange reagents from different lots or use reagents from other commercially available kits. The components of the kit are precisely matched for optimal performance of the tests.

2. Specimens with Hyperlipidemia and icterus show no effects on the detection results. But specimen with severe hemolysis will affect the color of the result, other test methods are suggested to use.

3. Allow the reagents and specimens to reach room temperature before use. Shake reagent gently before use.

4. Concentrated washing liquid will produce crystal at room temperature, should be diluted completely before use.

5. Never reuse microplate sealing membrane.

6. Samples containing anti-sperm antibody, anti-endometrial antibody will not affect the results.

7. Each component of the kit was inactivated, however, it should be regarded as potentially infectious.

PERFORMANCE CHARACTERISTICS

• Expected value

The cut-off value of TSH concentration for healthy subjects is 0.5~5.0 mIU/L.

• Sensitivity

The detection limit of the assay is approximately 0.15 mIU/L.

• Precision CV＜15%.
• Specificity: No cross reactions with LH, FSH and HCG.