IMMUNOASSAY METHOD AND KIT THEREFOR

PROBLEM TO BE SOLVED: To accelerate the direct visual evaluation of the flow of an aqueous-phase medium and an unreacted component and the results of measurement and to minimize other false positive results on a filter element by making a suspension contain a coloring substance sufficient in amount to provide color capable of masking the color of coloring particles contained and removing the color of the coloring substance from a gathered complex. SOLUTION: For improving the flow of a substance through a collecting filter element and minimizing the non-specific binding of an immunoreactive substance to various elements, a device and material for removing undesired contaminants from a urine sample are obtained. A filter dropper is formed of a blow-formed polyethylene body 10 and comprises a soft spherical part 12 at its one end and a long cylindrical housing or nozzle 14 at the other end. The filter dropper is, for example, 2.75 in length, the spherical part 12 is 0.5 in diameter, and the nozzle 14 is 0.25 in diameter. The device comprises a wall thickness of approximately 0.023 in. A porous ultrahigh- molecular polyethylene plug 16 with outer diameter larger than the inner diameter of the nozzle 14 is pressed into the nozzle 14. The plug 16 enables a test sample to be passed and flowed through the collecting filter element within approximately one minute.