One-step enzyme immunoassays in which enzyme-antibody conjugate or label and enzyme substrate are separated until separation of bound and free enzyme conjugate or label is complete. This separation is accomplished by using variable flow paths, immobilization of substrate at the test line, placement of...http://www.google.ca/patents/US20040152207?utm_source=gb-gplus-sharePatent US20040152207 - Enzyme substrate delivery and product registration in one step enzyme immunoassays
