An assay device for performing an assay on a liquid sample using a detection conjugate capable of binding to an antigen and containing a label. The device includes a substrate surface having a sample addition zone, a reaction zone and an absorbing zone, the zones being connected by at least one fluid passage, wherein the device has a first functionality verifying feature located between the sample addition zone and the reaction zone, and a second functionality verifying feature located within the absorbing zone. Both functionality verifying features are capable of undergoing a detectable change when contacted by the sample, in which the assay device further includes at least one alignment verification zone. There is further provided a kit of parts and a method of conducting an assay.
1. A method of conducting an assay, comprising:
verifying the alignment of an assay device in a reader using at least one alignment verification zone disposed on the assay device;
adding a sample and detecting at least one reaction between the sample and one or more reagents using the assay device, the assay device having at least one fluid passage, a sample addition zone, a reaction zone and an absorbing zone, said one or more reagents including a detection conjugate capable of binding to an antigen and containing a label;
determining the presence of the label in a first area downstream from the sample addition zone in which the absence of signal or detection of an insufficient signal is taken as an indication of error;
said method further comprising a calibration step, wherein the amount of at least one label, pre-dispensed in a zone for calibration on the assay device, separate from the fluid passage, is determined and the amount compared to a preset value.
2. The method according to claim 1 , the reader including a display, the method further comprising:
displaying an error message without delay, including prompting a user to remove the assay device from the reader and attempt a new assay.
3. The method according to claim 1 , wherein the result of the analysis is adjusted based on the result of the calibration step.
4. The method according to claim 3 , the reader including a display, the method further comprising:
displaying a margin of error, based on the result of said calibration step to a user together with the result of the analysis.
5. The method according to claim 1 , wherein said predispensed label is the same label used in said detection conjugate.
6. The method according to claim 1 , further comprising:
using the reader, determining the amount of detection conjugate which has passed the reaction zone based on the amount of label detected.
7. The method according to claim 1 , wherein the kinetics of the reaction are determined based on the amount of detection conjugate determined over a range of time.
8. The method according to claim 1 , further comprising:
measuring the progression of the mixture of the sample and detection conjugate and recording the kinetics of the conjugate transport.