Automatic analyzer and analysis method

An automatic analyzer comprising:

• a first standby position where a sample is waiting to be dispensed;
• a sample dispensing unit configured to dispense the sample sucked from the first standby position into a reaction vessel;
• a reagent dispensing unit configured to dispense first, second and third reagent into the reaction vessel;
• an input unit configured to receive analysis contents inputted by an operator relating to a type of analysis to be performed on the sample;
• a control unit configured to determine whether a reaction inhibitor having a chemical structure similar to a binding site of the first reagent, to the third reagent is expected to be present in the sample based on the inputted analysis contents and to control the sample dispensing unit and the reagent dispensing unit, wherein if the reaction inhibitor is not expected to be present, the sample is dispensed from the first standby position to a first reaction vessel according to a first mode and, if the reaction inhibitor is expected to be present, the sample is dispensed from the first standby position to a second reaction vessel or a second standby position according to a second mode;
• a measurement unit configured to measure a mixed solution of the sample and the first second and third reagents, and
• a determination unit configured to determine whether a result measured by the measurement unit is within a predetermined range determined in advance based on the analysis contents, wherein
• the first reagent comprises a biotinylated antibody;
• the second reagent comprises a labelled antibody including a substance emitting light detectable by the measurement unit;
• and the third reagent comprises insoluble carriers carrying an antibody or antigen on a particle surface having a binding specificity for the first reagent,
• if the control unit determines that the reaction inhibitor is not expected to be present, the control unit performs the first mode, in which the sample from the first standby position, the first reagent, and the second reagent are mixed with each other in the first reaction vessel to prepare a first mixed solution and the third reagent and the first mixed solution are mixed with each other in the first reaction vessel after a lapse of predetermined time to prepare a second mixed solution;
• and, if the control unit determines that the reaction inhibitor is expected to be present, the control unit performs the second mode in which the first reagent and the third reagent are mixed with each other in the first reaction vessel to prepare a third mixed solution and the sample from the second reaction vessel or the second standby position, the second reagent, and the third mixed solution are mixed with each other in the first reaction vessel after a lapse of predetermined time to prepare a fourth mixed solution, and
• if the first mode is performed, and the determination unit has determined that the result measured by the measurement unit is not within the predetermined range determined in advance based on the analysis contents, the control unit is configured to control to perform the second mode.