... tumors. 2. Principle When a sample is added to the Malachite green Test Strip, the sample begins to mix with the colloidal goldlabeled ... by capillary action. In the sample region of the test strip, if Malachite green is present, the second specific antibody captures the colloidal ... labeled antibody and bound Malachite green, forming a colored line or band in the “T” window of the test strip. As an ...