Method for measuring physiologically active substance of biological origin, program for implementing the same, and apparatus for measuring physiologically active substance of biological origin

An apparatus for measuring a physiologically active substance of biological origin, comprising:

• a liquid mixture retaining device for retaining liquid mixture of a sample containing a predetermined physiologically active substance of biological origin and a limulus amoebocyte lysate, LAL, while allowing light to be incident on the liquid mixture and for promoting a reaction in the liquid mixture;
• a stirring device for stirring the liquid mixture in the liquid mixture retaining device;
• a light incidence device for entering light into the liquid mixture in the liquid mixture retaining device;
• a light receiving device for receiving transmitted light or scattered light of the incident light from the liquid mixture and converting the transmitted light or the scattered light into an electric signal;
• a determining device for determining a reaction-starting time between the physiologically active substance and LAL in the sample from the electric signal converted in the light receiving device;
• and
• a deriving device s for deriving an existence or concentration of the physiologically active substance in the sample with reference to a relationship set in advance between the reaction-starting time and the concentration of the physiologically active substance, wherein
• the determining device determines a reaction-starting time as a time at which a difference between a detected signal value at one acquisition time among acquisition times set at predetermined time intervals, where a signal obtained by subjecting the electric signal to a predetermined calculation or the electric signal itself is used as a detected signal value, and a detected signal value at a previous acquisition time or an absolute value of the difference becomes not less than or exceeds a previously defined threshold.