Typhoid IgG/IgM Rapid Test Device
Test Principle
The Typhoid IgG/IgM Rapid Test Device is a lateral flow chromatographic immunoassay. The test cassette consists of: 1) a burgundy colored conjugate pad containing recombinant S. typhoid H antigen and O antigen conjugated with colloid gold (Typhoid conjugates) and rabbit IgG-gold conjugates, 2) a nitrocellulose membrane strip containing two test bands (IgG and IgM bands) and a control band (C band). The IgM band is pre-coated with monoclonal anti-human IgM for the detection of IgM anti-S. typhi, IgG band is pre-coated with reagents for the detection of IgG anti-S. typhi , 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 cassette, the test specimen migrates by capillary action across the test cassette. Anti-S. typhi IgM if present in the patient specimen will bind to the Typhoid conjugates. The immunocomplex is then captured on the membrane by the pre-coated anti-human IgM antibody, forming a burgundy colored IgM band, indicating a S. typhi IgM positive test result.
Anti-S. typhi IgG if present in the patient specimen will bind to the Typhoid conjugates. The immunocomplex is then captured by the pre-coated reagents on the membrane, forming a burgundy colored IgG band, indicating a S. typhi IgG positive test result.
Absence of any test bands 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 test bands.
Otherwise, the test result is invalid and the specimen must be retested with another device.
Assay Procedure
1.Typhoid IgG/IgM Rapid Test Device（Whole Blood/Serum/Plasma）
Allow test device, specimen, buffer and/or controls to reach room temperature (15-30°C) prior to testing.
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.
For Whole Blood, Serum or Plasma specimens:
Hold the dropper vertically and transfer 2 drops of specimen (or approximately 50 µL) to the specimen well (S) of the test device, then add 1 drop of buffer and start the timer.
For Fingerstick Whole Blood specimens:
To use a capillary tube: Fill the capillary tube and transfer approximately 50 µL (or 2 drops) of fingerstick whole blood specimen to the specimen well (S) of the test device, then add 1 drop of buffer and start the timer.
3. Wait for the colored line(s) to appear. Read results at 10 minutes. Do not interpret results after 20 minutes.
2 Typhoid IgG/IgM Rapid Test Device（Serum/Plasma）
1. Bring the specimen and test components to room temperature. Open the pouch at the notch and remove device. Place the test device on a clean, flat surface.
2. Fill the pipette dropper with the specimen. Holding the dropper vertically, dispense 1 drop
(about 40 µL) of specimen into the sample well making sure that there are no air bubbles. Then add 1 drop (about 35-50 µL) of Sample Diluent immediately. Set up timer.
3. Results can be read in 15 minutes. Positive results can be visible in as short as 1 minute. Don’t read result after 15 minutes.
