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Principle

It is a rapid chromatographic immunoassay for the qualitative detection of antibodies (IgG and IgM) to CMV in Whole blood, Serum or Plasma. Each test consists of: 1) a burgundy colored conjugate pad containing CMV recombinant envelope antigens conjugated with Colloid gold (CMV conjugates) and rabbit IgG‐gold conjugates,2) a nitrocellulose membrane strip containing two test bands (T1 and T2 bands) and a control band (C band). The T1 band is pre‐coated with the antibody for the detection of IgM anti‐CMV, T2 band is coated with antibody for the detection of IgG anti‐CMV, and the C band is pre‐coated with goat anti rabbit IgG. When an adequate volume of test specimen is dispensed into the sample well of the test cassette, the specimen migrates by capillary action across the cassette. IgG anti‐CMV, if present in the specimen, will bind to the CMV conjugates. The immunocomplex is then captured by the reagent pre‐coated on the T2 band, forming a burgundy colored T2 band, indicating a CMV IgG positive test result and suggesting a recent or repeat infection. IgM anti‐CMV if present in the specimen will bind to the CMV conjugates. The immunocomplex is then captured by the reagent coated on the T1 band, forming a burgundy colored T1 band, indicating a CMV IgM positive test result and suggesting a fresh infection. Absence of any T bands (T1 and T2) suggests a negative result. The test contains an internal control (C band) which should exhibit a burgundy colored band of the immunocomplex of goat anti rabbit IgG/rabbit IgG‐gold conjugate regardless of the color development on any of the T bands. Otherwise, the test result is invalid and the specimen must be retested with another device.

Procedure

1. Bring the pouch to room temperature before opening it. Remove the test device from the sealed pouch and use it as soon as possible.

2. Place the test device on a clean and level surface.

3. Hold the dropper vertically and transfer 1 drop of Plasma/serum specimen (approximately 10μl) or 2 drops of whole blood specimen (approximately 20μl) to the specimen well(S) of the test device, then add 2 drops of buffer (approximately 80μl) and start the timer. See illustration below.

4. Wait for the colored line(s) to appear. Read results at 15 minutes. Do not interpret the result after 20 minutes.

Notes:
Applying sufficient amount of specimen is essential for a valid test result. If migration (the wetting of membrane) is not observed in the test window after one minute, add one more drop of buffer to the specimen well.

Accuracy:
The results demonstrated >99% overall accuracy of the hCG One Step Pregnancy Combo Test Device when compared to the other urine membrane hCG test.

Results

IgM POSITIVE: * The colored line in the control line region (C) appears and a colored line appears in test line region 1 (T1). The result indicates the presence of CMV specific IgM antibodies.

IgG POSITIVE: * The colored line in the control line region (C) appears and a colored line appears in test line region 2 (T2). The result indicates the presence of CMV specific IgG antibodies.

IgG AND IgM POSITIVE: * The colored line in the control line region (C) appears and two colored lines should appear in test line regions 1 and 2 (T1 and T2). The color intensities of the lines do not have to match. The result indicates that the presence of both CMV specific IgG and IgM antibodies.

*NOTE: The intensity of the color in the test line region(s) (T1 and/or T2) will vary depending on the concentration of CMV antibodies in the specimen. Therefore, any shade of color in the test line region(s) (T1 and/or T2) should be considered positive

NEGATIVE RESULT:
The colored line in the control line region (C) appears. No line appears in test line regions 1 or 2 (T1 or T2).

INVALID RESULT:

Control line fails to appear. Insufficient specimen volume or incorrect procedural techniques are the most likely reasons for control line failure. Review the procedure and repeat the test with a new test device. If the problem persists, discontinue using the test kit immediately and contact your local distributor.