Microassay On A Card

NRL developed the Microassay on a Card (MAC), which is a portable, handheld, noninstrumental immunoassay that can test for the presence of a wide variety of substances in the environment. The MAC assay card.The MAC is a simple device to use. A drop of test solution is placed on one side of the card and within minutes a color is developed on the other side in proportion to the amount of substance in the test solution. The MAC is self-contained and self-timed; no reagents or timing are necessary. The MAC can be configured with multiple wells to provide simultaneous testing for multiple species.

MAC's advantages include:


  • rapid and sensitive response: completed in under five minutes with nanogram- per-milliliter sensitivity;

  • a visible positive result: a color develops, indicating the presence of a substance;

  • designed for field use: the dry chemistry requires only the test solution;

  • no instrumentation required;

  • results remain permanent for up to one year; and

  • no toxic or corrosive reagents are used.


As envisioned, the MAC could be used as an on-site screen for drugs of abuse in urine or saliva. It could also be used for on-the-job drug testing and identifying seized solid materials. Other applications include tests for pregnancy, surveys for environmental contaminants (pesticides), and diagnostics for disease organisms (toxins).

Link to Highlights of NRL's First 75 Years