TB Correlative IFN-γ Release Assay

TB Correlative IFN-γ Release Assay (结核感染T细胞检测试剂盒) is a one-step, quantitative , enzyme-linked immunosorbent assay (ELISA) test kit, based on the Double Antibody Sandwich ELISA principle, which is used to detect Interferon Gamma Release in human Serum or Whole Blood specimen.

Detailed information of TB Correlative IFN-γ Release Assay

  1. General and Technical information of this TB test kit;
  2. Packing specification of this Microwell style TB test kit (gross weight and carton dimension etc.);
  3. Specimen used to carry out the assay, and the requirements on specimen collection, storage and processing; and,
  4. Specific immuno assay principle used in this Tuberculosis Test Kit.

Main technical information of this IFN-Y Microwell test kit is listed in the following table:

Catalog No.:TB 8134
Description:TB Correlative IFN-γ Release Assay
Category:Respiratory Tract Disease
Style:Microwell
Unit:Box
Specimen:Serum, Whole Blood
No. of Step:One Step
Reading Time:10 min-16 Hour
Cut Off:
Specification:---
Quan. or Qual.:Quantitative
Sensitivity:89%
Specificity:93%
Assay Principle:Double Antibody Sandwich ELISA

The standard kit size of Tuberculosis Microwell Test Kit is 96 Tests per box; 40 boxes per carton; 48T and 480T packing specifications are available for choice.


Tests per Kit:96 Tests
Dimension of Kit Box:13.5 * 9.0 * 8.0 CM
Boxes per Carton:40 Kits
G.W. per Carton:15.0 KG
Carton Dimension:59 * 45 * 38 CM
Carton Volume:0.100 CBM

Materials Provided

  • MICROWELL PLATE: 1 plate;
  • NEGATIVE CONTROL: 1 vial;
  • POSITIVE CONTROL SERUM: 1 vial;
  • SPECIMEN DILUENT: 1 vial;
  • HRP-CONJUGATE REAGENT: 1 vial;
  • WASH BUFFER: 1 bottle;
  • CHROMOGEN SOLUTION A: 1 vial;
  • CHROMOGEN SOLUTION B: 1 vial;
  • STOP SOLUTION: 1 vial;
  • PLASTIC SEALABLE BAG: 1 piece;
  • CARDBOARD PLATE COVER;
  • PACKAGE INSERT: 1 copy.

To carry out the assay with a TB Correlative IFN-γ Release Assay, Serum or Whole Blood should be collected according to the instructions given in the Instruction For Use included in the test kit. After collecting, it is preferable to perform the testing as early as possible; if not viable, the specimen should be stored properly. A general introduction about the collection, and storage of the specimens is given below.

Serum Collection

Collect blood specimen into a red top blood collection tube by vein puncture, which contains no anticoagulants.

Allow the blood to clot, or separate the serum by centrifugation.

Carefully withdraw the serum into a new pre-labeled tube.

Whole Blood Collection

Whole blood can be collected with blood collection tube with venipuncture into blood collection tube (containing EDTA, citrate or heparin).

Or, by lancet lancing. Clean the area to be lanced with an alcohol swab. Squeeze the end of the fingertip and pierce with a sterile lancet. Wipe away the first drop of blood with sterile gauze or cotton. Take a dropper provided, while gently squeezing the dropper tube, immerse the open end in the blood drop and then gently release the pressure to draw blood into the dropper.

Serum, Whole Blood Storage Condition

Test specimens as soon as possible after collecting.

The specimens can be stored up to 3 days at 2-8°C if not tested immediately. The specimens should be frozen at -20°C for longer time storage. Don’t freeze and thaw the specimens for many times.

Prior to testing, bring frozen specimens to room temperature slowly and mix gently.

Specimens containing visible particulate matter should be clarified by centrifugation before testing.

Do not use samples demonstrating gross lipemia, gross hemolysis or turbidity in order to avoid interference on result interpretation.

Double Antibody Sandwich ELISA method is used in this TB Correlative IFN-γ Release Assay to detect the Interferon Gamma Release in human Serum or Whole Blood specifically. The introduction of this Double Antibody Sandwich ELISA testing principle is given blow.

ELISA Double Antibody Sandwich Method Illustration

With this type of ELISA test kits, the detection target usually is hormone protein or viral antigen.

In the test kit, monoclonal or polyclonal antibodies specific to the target protein or antigen are used as capturer, which are pre-coated on the polystyrene microwell strips. The sample from the patient, such like urine, serum or plasma sample is added to the microwells. And a second antibody conjugated with horseradish peroxidase (HRP) is used as the detector, which then is added to the microwells. Usually, the samples and the second antibody conjugate are added to the microwell in the same time, thus it is a one-step assay process.

During incubation, the specific immuno-complex formed in case of presence of the target antigen or protein in the sample, and is captured on the solid phase.

After washing to remove sample serum proteins and unbound HRP-conjugate, Chromogen solutions containing tetramethyl benzidine (TMB) and urea peroxide are added to the wells. In presence of the antibody-antigen-antibody (HRP) "sandwich" immuno complex, the colorless Chromogens are hydrolyzed by the bounded HRP-conjugate to a blue colored product. The blue color turns yellow after stopping the reaction with sulfuric acid, indicating a positive result. The amount of color can be measured and is proportional to the amount of antigen or protein in the sample.

Wells containing samples negative for the target antigen or protein remain colorless.