Abstract: The present invention relates to microspheres comprising protein signal precursor molecules, or a carrier protein bonded to signal precursor molecules, wherein said signal precursor molecules are activatable to generate a detectable signal while remaining bonded to the carrier protein. Also disclosed is a method of making such microspheres comprising the steps of mixing protein molecules with a matrix former in solution; adding a reducing reagent to the mixture; removing the reducing reagent; and removing the matrix former to leave microspheres of protein molecules. Also disclosed are bioassay methods using the microspheres to provide signal amplification, including an amplification cycling procedure.

Abstract: The present invention relates to microspheres comprising protein signal precursor molecules, or a carrier protein bonded to signal precursor molecules, wherein said signal precursor molecules are activatable to generate a detectable signal whilst remaining bonded to the carrier protein. Also disclosed is a method of making such microspheres comprising the steps of mixing protein molecules with a matrix former in solution; adding a reducing reagent to the mixture; removing the reducing reagent; and removing the matrix former to leave microspheres of protein molecules. Also disclosed are bioassay methods using the microspheres to provide signal amplification, including an amplification cycling procedure.

Abstract: The present invention relates to microspheres comprising protein signal precursor molecules, or a carrier protein bonded to signal precursor molecules, wherein said signal precursor molecules are activatable to generate a detectable signal whilst remaining bonded to the carrier protein. Also disclosed is a method of making such microspheres comprising the steps of mixing protein molecules with a matrix former in solution; adding a reducing reagent to the mixture; removing the reducing reagent; and removing the matrix former to leave microspheres of protein molecules. Also disclosed are bioassay methods using the microspheres to provide signal amplification, including an amplification cycling procedure.

Abstract: A method for generating and localizing a signal in a solid phase substrate detection system comprises applying a solution of target material to a substrate; binding the target with a specific affinity molecule having an attached label, the label comprising multiple signal precursor molecules; applying a carrier to the substrate, and treating the label to convert the signal precursor molecules to signal generating molecules. The carrier comprises solvent for the label and thickener for localizing the signal. The carrier may include developer that converts signal precursor molecules to signal generating molecules. Developer is not necessary if the signal precursor molecules are converted to signal generating molecules by e.g. temperature change, pH change, sonication, light irradiation, microwave heating. A test device for detecting target in a fluid sample, and a kit of parts for determining the presence of target in a fluid sample are also disclosed.

Abstract: A method for generating and localizing a signal in a solid phase substrate detection system comprises applying a solution of target material to a substrate; binding the target with a specific affinity molecule having an attached label, the label comprising multiple signal precursor molecules; applying a carrier to the substrate, and treating the label to convert the signal precursor molecules to signal generating molecules. The carrier comprises solvent for the label and thickener for localizing the signal. The carrier may include developer that converts signal precursor molecules to signal generating molecules. Developer is not necessary if the signal precursor molecules are converted to signal generating molecules by e.g. temperature change, pH change, sonication, light irradiation, microwave heating. A test device for detecting target in a fluid sample, and a kit of parts for determining the presence of target in a fluid sample are also disclosed.