Abstract: Complement immunoassay using liposomes is improved by pretreatment of a sample solution before determination of analyte comprising acidifying or alkalinizing the sample solution, followed by changing the pH to about neutral so as to remove influences caused by interfering substances present in the sample.

Abstract: As method of determining an analyte is described, where a medium suspected of containing an analyte is drawn into a capillary tube by capillary action, such that if the analyte is present, it becomes immobilized in the tube. This medium is expelled from the tube and, optionally, one or more additional reagents are similarly drawn up and expelled. When the last fluid is expelled from the tube, a pendulous drop is caused to form at the opening of the capillary tube and is examined for the presence or intensity of the signal, which is related to the presence or amount of analyte in the medium.

Abstract: Reagents for a liquid-phase immunodiagnostic assay (LIDA) method comprise a first enzyme; a second enzyme; a first agent which is capable of binding with an analyte to form a complex, the agent being attached to one of the first and second enzymes; and a complex-binding agent attached to the remaining enzyme, wherein the first enzyme is capable of interacting with a substrate for the first enzyme together with any necessary additional substrates for the first enzyme to produce a substrate for the second enzyme, and wherein the second enzyme is capable of interacting with the substrate produced by the first enzyme together with any necessary additional substrates, such that occurrence of the second of the interactions is detectable. The reagent optionally further comprises a scavenger substance capable of inactivating the substrate produced by the first enzyme.

Abstract: The present invention involves a variety of assay methods and devices for screening or diagnosing the occurrence of extrahepatic biliary atresia. In particular the methods and devices involve an antibody specifically for the detection of dipeptidyl peptidase IV in a test sample as indicative of extrahepatic biliary atresia.