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Specifications of  One step anti HIV serum test kit supplied by World of  Health Biotech, Beijing, China, July 2007 .   

TEST KIT IDENTIFICATION

 1.0    Name of kit:         WOHBC One-Step Anti-HIV(1+2) Serum Test

 2.0    Indication:           For In Vitro Diagnosis of HIV(1+2) infection

 3.0    Package Size:     One test per kit

4.0    Active Ingredients:

4.1    Coated Antibodies and Antigen:

4.1.1          Control region:  Goat anti-HIV polyclonal antibody

4.1.2          Test region:  Recombinant HIV antigens

4.2    Labeled Antigen:

Colloidal gold conjugate of anti-human IgG monoclonal antibody

5.0      Assay Protocol:

5.1    Assay Procedure:

Read the test instructions for WOHBC One-Step Anti-HIV test carefully before starting the assay. Allow serum samples to warm up to room temperature before testing.

5.1.1          Remove the test device from its foil pouch, place it on a flat surface and label it with patient ID. Use the device as soon as possible.

5.1.2          Using the plastic pipettor provided, draw the sample (3 uL) into the pipette until the level is at the bottom of the first bulb (do not draw sample past the Fill Line). Dispense this amount of sample into the sample well of the cassette. Add about 3-4 free falling drops of diluent (100 μL) into the sample well of the cassette.

5.1.3          Wait 10-15 minutes and read results. It is important that the background is clear before the result is read. Results obtained after 15 minutes should be considered invalid.

5.2    Interpretation of Results:

5.2.1          Negative: Only one color band appears on the control region. No apparent band on the test region.

5.2.2          Positive: In addition to a pink colored control band, a distinct pink colored band will also appear in the test region.

5.2.3          Invalid: No visible band at all or no colored line appears on the control region. Repeat test with a new test kit.

6.0      Specificity:

Cross reactivity has been tested with Anti-HCV, Anti-TP (Syphilis), Anti-HBc positive serums, no cross reactivity with above serums.

7.0      Storage:  2 to 30^oC

8.0      Expiration Dating:  24 months from date of manufacture

9.0      Method of Manufacture:

9.1    Nitrocellulose Membrane Manufacture:

9.1.1          The purified recombinant antigen, diluted in phosphate buffer saline, is coated on the test region. Simultaneously, goat anti-HIV antigen, diluted in phosphate buffer saline, is coated on the control region.

9.1.2          The coated membrane is dried for a minimum of 24 hours then sealed in an aluminum bag which contains silica gel desiccant.

9.2    Anti-human IgG monoclonal antibody colloidal gold conjugate pad manufacture:

9.2.1          A buffer solution containing anti-human IgG monoclonal antibody/ colloidal gold conjugate is coated onto non-woven cloth sheets.

9.2.2          The coated non-woven cloth is dried for minimum 24 hours then sealed in an aluminum bag which contains desiccant.

9.3    Test Device Assembly:

9.3.1          The coated membrane S1, the conjugate pad S4, and an absorbent pad is applied to an adhesive-coated backing.

9.3.2          A 2-part waterproof label is applied over the conjugate pad and the absorbent pad, the assembled sheet of material is cut into strips. The test strips are then vacuum-dried for a minimum of 4 hours.

9.3.3          The assembled test strip is sealed in a plastic cassette casing. The cassette device is sealed in an aluminum pouch along with a desiccant packet.

10.0   Clinical Trials:

To establish the sensitivity and specificity of WOHBC One-Step Anti-HIV test kit relative to other rates of qualitative serum Anti-HIV tests, 559 clinic samples were studied.  Another commercially available qualitative test kit (Organon Anti-HIV) was used to compare with WOHBC One-Step Anti-HIV test kit for relative sensitivity and specificity in 559 serum samples. Only 4 samples were discordant. In turn, the agreement is 99.28%. The results are shown in Table 1.

        Table 1 - Comparison of One-step Anti-HIV with Organon product for 559 cases

11.0   Stability Studies:

It is well known that immunochemicals are quite stable at room temperature if the materials are kept in dry condition. The chemicals used in the One-Step Anti-HIV device are either dried on the membrane or chemical pad. The final test device is then sealed in an aluminum pouch with a desiccant. Accelerated stability testing has been carried out in this study to establish the shelf life and predict the expiration date of the tests.

Three lots of One-Step Anti-HIV test kit have been used for this study. The test devices in aluminum pouches were kept in the incubator at 42°C or room temperature. The test kits were removed from their storage and tested with positive and negative control panels. The results are shown in Table 2 and 3.

Table 2 - Results of Stability study on One-Step Anti-HIV test kits at 42°C

Table 3 - Results of Stability study on One-Step Anti-HIV test kits at room temperature

 The data collected to date indicate that One-step Anti-HIV test kits are stable for at least 12 months at 2-30°C.

 12.0      Quality Control:

12.1      Appearance: All materials are visually inspected before their use in manufacture.

12.2      Specificity: 10 test kits are randomly selected and tested with Anti-HIV negative control panel. All test results must be negative.

12.3      Cut Off: 10 test kits are randomly selected and tested with Anti-HIV positive control panel. All test results must be positive.

12.4      Internal Control: A colored band must appear in the control region of the membrane with each tested kit, which indicating proper performance and reagent reactivity.

12.5      Reproducibility: Randomly selected test kits from different lots must give the same results when assaying the same sample.

13.0      References:

13.1      Popovic M, Samgadharan, M.G., Read, E., and Gallo, R.C.Detection, isolation, and continuous production of cytopathic retroviruses (HTLV-III) from patients with AIDS and pre AIDS. Science 224; 497-500, 1984.

13.2      Gallo, R.C., et al., Detection and isolation of cytopathic retroviruses (HTLV-III) from patients with AIDS and at risk for AIDS. Science 1984; 224: 500-503.

13.3      Curran J.W. et al., The epidemiology of AIDS: Current status and future prospects. Science 1985; 229: 1352-1357.

13.4      Plot. P., Plummer, F.A., Mhalu, F.s., Lmboray, J-L, Chin, J., and Mann, J.M., AIDS, An international perspective, Science 239: 573-579,1988.