Patent ID: 8462340

Claim:
A gel particle measuring apparatus for detecting particles produced from a target substance in a sample by a gelation reaction, the apparatus comprising: a sample cell that has at least a transmission portion through which light transmits from one side to another side and that accommodates a sample containing a target substance as a measuring object and a solution containing a reagent causing gelation of the target substance to produce gel particles; a stirring device for stirring a mixed solution comprising the sample and the solution containing the reagent in the sample cell continuously so as to disturb gelation of the mixed solution as a whole; a coherent light source that is provided outside the transmission portion of the sample cell and irradiates the continuously mixed solution comprising the sample and the solution containing the reagent in the sample cell with coherent light; a transmitted light detecting device that is provided at a position outside the transmission portion of the sample cell and on an opposite side of the coherent light source and that is used for detecting transmitted light through the continuously mixed solution comprising the sample and the solution containing the reagent in the sample cell; a transmitted light fluctuation measuring device for measuring a fluctuation component of the transmitted light based on a detection output of the transmitted light detecting device; and a gel particle production determining device for determining at least a production state of gel particles in the continuously mixed solution, which corresponds to timing of phase transition of the mixed solution from a sol phase to a gel phase, and which includes the emerging time of the gel particles which is the starting point of the production of the gel particles, based on a result of measurement of the transmitted light fluctuation measuring device, wherein the gel particles appear when gelation of the continuously mixed solution as a whole is disturbed by said stirring device.