Devices and methods for detecting norovirus on surfaces

A method for detecting a presence of norovirus residing in a test sample, said method comprising:

• i) providing a flow-through assay device that comprises a porous membrane in fluid communication with a conjugate pad, the conjugate pad comprising conjugated probes having particles modified with a binding member configured to bind with the norovirus and containing a fluorescent label, wherein the fluorescent label has a fluorescence emission lifetime of greater than about 1 microsecond;
• and
• wherein the porous membrane defines a detection zone comprising a test line within which is immobilized a norovirus antibody configured to bind with the norovirus, and a control line positioned downstream from the test line, wherein the control line has immobilized within a norovirus G2 antibody configured to bind with the conjugated probes;
• ii) contacting the conjugate pad with the test sample and allowing the particles to flow to the detection zone;
• iii) subjecting the test line to pulses of illumination to generate a detection signal and, after a certain period of time has elapsed following a pulse, measuring an intensity of the detection signal, wherein a fluorescence reader is employed to provide an illumination and measure the intensity of the detection signal,
• iv) subjecting the control line to pulses of illumination to generate a calibration signal and after a certain period of time has elapsed following a pulse, measuring an intensity of the calibration signal;
• and
• v) comparing the intensity of the detection signal to the intensity of the calibration signal, wherein the amount of the norovirus within the test sample is proportional to the intensity of the detection signal as calibrated by the calibration signal.