Typhoid IgG/IgM Test Kit

Purpose and Mechanism

The typhoid IgG/IgM rapid test kits are used for the prompt detection of anti-Salmonella typhi immunoglobulin G and immunoglobulin M in human blood serum or plasma. Typhoid fever is caused by a gram-negative bacterium known as Salmonella Typhi. It is caused by the intake of contaminated food and water and can affect multiple organs. Therefore, it is essential to diagnose and treat it promptly. A lateral flow immunochromatographic assay is used in the typhoid IgG/IgM rapid test. It contains an IgG-gold conjugate and a pad with conjugate S. typhi H and O antigens labelled with colloidal gold. It has a nitrocellulose membrane with two regions: a test region and a control region. The test line “G” is coated with an anti-human IgG, and the test line “M” is coated with anti-IgM. When the specimen is added to the sample well, the S. typhi IgG and IgM react and form complexes. For control, the membrane at last contains goat anti-mouse IgG.

User Guide

• Remove the card from the pouch and place it on a flat surface.
• Bring the specimen and the card to room temperature.
• Add 25-30 µL of the specimen to the sample well on the card.
• Add 2-3 drops (75-80 µl) of assay buffer into the assay buffer well.
• Let the card sit for 15 minutes and then read the results.

Interpretation

• Negative: Appearance of a single line on the control region indicates a negative result for the typhoid IgG/IgM antibody.
• Positive IgG:If there are two lines, one on the IgG test region and one on the control region, then the result is positive for the S. typhi IgG antibody.
• Positive IgM: If there are two lines, one on the IgM test region and one on the control region, then the result is positive for the S. typhi IgM antibody.
• IgG and IgM Positive: If there are three lines on the card, one in the IgG test region, one in the IgM test region, and one in the control region, then the sample is positive for both IgG and IgM.
• Invalid: If the card has no line, the reagent has degraded, or there was a mistake in the execution of the test.