In vivo immunoassay system

A film layer configured for being used in an in-vivo device, the film layer comprising:

• a cut-off active material having a threshold reaction to a substance or parameter of gastrointestinal (GI) fluid of a person;
• a plasticizer configured, together with the cut-off sensitive material, for forming the film layer;
• and
• an auxiliary active material, wherein the film layer is configured to be breached after a predetermined amount of time of exposure to the GI fluid.

A swallowable in-vivo immunoassay device, the immunoassay device comprising:

• a lateral flow strip extending between a fluid intake end and a distal end, the lateral flow strip including a test pad and a backing card juxtaposed with the test pad, wherein the backing card is made of a material allowing at least partial passage of light therethrough;
• an illumination module including at least one illumination source configured for directing light towards the backing card;
• and
• a sensor module including at least one sensor configured for receiving light from the illumination module, wherein the at least one sensor is positioned such that the test pad is disposed between the at least one sensor and the backing card.