Method for detecting a target particle in biosample containing pancreatic juice

A method for detecting a target particle in a biosample containing pancreatic juice, comprising:

• (a) preparing a sample solution which contains a biosample containing pancreatic juice and a fluorescent probe capable of binding to a target particle, and binding the fluorescent probe to the target particle contained in the biosample, in the sample solution;
• and
• (b) calculating the number of molecules of the target particles bound to the fluorescent probes existing in the sample solution prepared in the (a);
• the calculating of the number of molecules of the target particles bound to the fluorescent probes in the (b) being carried out by:
• moving a position of a light detection region of the optical system in the sample solution with use of an optical system of a confocal microscope or a multiphoton microscope;
• detecting a light signal emitted from the fluorescent probe in the state of being bound to the target particle in the light detection region, thereby individually detecting the target particles bound to the fluorescent probes while moving the position of the light detection region of the optical system in the sample solution;
• and
• counting the number of the individually detected target particles bound to the fluorescent probes to thereby count the number of molecules of the target particles detected during the moving of the position of the light detection region;
• wherein a light emission property of light emitted from the fluorescent probe is different between a state where the fluorescent probe is bound to the target particle and a state where the fluorescent probe is present alone;
• and the wavelength of emitted light in a state where the fluorescent probe is bound to the target particle is 600 nm or longer.