Abstract: A method of monitoring an immunoassay comprises determining the position of the flow edge of fluid across an immunoassay region. This allows, for example, early detection of possible errors in the test. For example the speed of the movement of the fluid flow edge may be determined from measurements of the position of the fluid flow edge at times throughout the test, and the determined speed may be compared with one or more thresholds to determine whether the test is proceeding correctly. A further method of monitoring an immunoassay comprising monitoring the variation with time of a reference zone of an immunoassay region. This can provide the user with early information as to whether the test is proceeding correctly. The above methods may also be used to provide methods to improve the run conditions of a test during its development. The method may be applied to a competitive assay.

Abstract: According to a first aspect of the present invention there is provided an oral fluid collection device 1. The oral fluid collection device 1 comprises a handle 2, a swab holder 4, and a swab 3. The swab 3 is in the form of a hollow tube of absorbent material coaxially located about the swab holder 4, such that the swab 3 is supported by the swab holder 4 along the entire length of the swab 3.

Abstract: An oral fluid collection and transfer device comprises a collection device (10) and a test cartridge (100). The collection device includes a frame or chassis (14), and an absorbing pad (12) for absorbing oral fluid and which is secured around part of the frame with part of the frame protruding from the pad. A collapsible cover (16) covers the absorbing means and has apertures (68) for the ingress of oral fluid into contact with the absorbing pad. A cap (18) covers the part of the frame protruding from the absorbing pad. The cap and the cover latch together to surround the frame and the absorbing pad. The device also includes a fluid adequacy indicator (20) in the form of an electrical circuit with an LED (66) which is completed when the absorbing means has absorbed a predetermined volume of oral fluid.

Abstract: A screening device for performing an immunoassay test to detect the presence of a compound in a body fluid. The device includes a holder for removably receiving a membrane to which the fluid has been applied. Light is directed to the membrane. A photodetector measures the concentration of the light reflected back from the membrane. Specifically, the concentrations of reflected light from a control zone and a test zone are measured. Signals representative of the measured light concentrations are applied to a processor. If a specified concentration of predetermined light from a control zone on the membrane is detected, the processor considers the test to be successful. In the test is successful, the processor, based upon the measured concentration of reflected light from the test zone, generates data representative of the presence of the compound.

Abstract: The invention provides competitive immunoassay techniques for high sensitivity detection of delta-9-tetrahydro-cannabinol (cannabis; THC) employing a carrier conjugate of an intermediate in the biosynthesis of cannabis, more particularly 5-pentylresorcinol conjugated to a macromolecular carrier via its hydroxyl groups. By employing such a conjugate with anti-THC antibody in a lateral flow immunochromatography test device convenient on-site testing for low levels of cannabis in liquid samples may be achieved. Such testing is particularly favoured for roadside testing for cannabis in oral fluid samples.

Abstract: The present invention provides immunoassays which are highly specific for detection in biological samples of methamphetamine and other drugs of abuse of the methamphetamine group such as ecstasy and other ecstasy class drugs. More particularly, competitive assays are provided comprising: (a) contacting said sample with (i) a pseudoephedrine/carrier conjugate in which pseudoephedrine is linked via its hydroxyl group to the carrier and (ii) an antibody which is capable of binding both one or more drugs of the methamphetamine group and said conjugate; and (b) determining whether the binding of said antibody to said conjugate is reduced by the presence of said sample, a reduction in binding being indicative that the sample contains a methamphetamine group drug.

Abstract: A screening device for performing an immunoassay test to detect the presence of a compound in a body fluid. The device includes a holder for removably receiving a membrane to which the fluid has been applied. A light is directed to the membrane. A photodetector measures the concentration of the light reflected back from the membrane. Specifically, the concentrations of reflected light from a control zone and a test zone are measured. Signals representative of the measured light concentrations are applied to a processor. If a specified concentration of predetermined light from a control zone on the membrane is detected, the processor considers the test to be successful. In the test is successful, the processor, based upon the measured concentration of reflected light from the test zone, generates data representative of the presence of the compound.