Abstract:
There is provided a single particle detection technique based on a scanning molecule counting method, enabling individual detection of a single particle using light measurement with a confocal or multiphoton microscope, and quantitative observation of conditions or characteristics of the particle. The inventive technique of detecting a single particle in a sample solution detects light containing substantially constant background light from a light detection region with moving the position of the light detection region of the microscope in a sample solution to generate time series light intensity data; and detects individually a light intensity reduction occurred when a single particle which does not emit light (or a particle whose emitting light intensity in a detected wavelength band is lower than the background light) enters in the light detection region in the time series light intensity data as a signal indicating the existence of each single particle.
Abstract:
In the scanning molecule counting method using the light measurement with a confocal microscope or a multiphoton microscope, a measuring time is optimized with suppressing the scattering in a result small irrespective of light-emitting particle concentrations. In the inventive technique of detecting and analyzing the light from an light-emitting particle, there are repeated processes of detecting the light intensity from a light detection region with moving the position of the light detection region of an optical system in a sample solution by changing the optical path of the optical system of the microscope, and detecting the signals of the light of light-emitting particles individually, and based on the time taken for the number of the signals from the light-emitting particles to reach a predetermined number, the light-emitting particle concentration in the sample solution is determined.
Abstract:
In the scanning molecule counting method detecting light of a light-emitting particle in a sample solution using a confocal or multiphoton microscope, there is provided an optical analysis technique enabling the scanning in a sample solution with moving a light detection region in a broader area or along a longer route while making the possibility of detecting the same light-emitting particle as different particles as low as possible and remaining the size or shape of the light detection region unchanged as far as possible. In the inventive optical analysis technique, there are performed detecting light from the light detection region and generating time series light intensity data during moving the light detection region along the second route whose position is moved along the first route, and thereby, the signal indicating light from each light-emitting particle in a predetermined route is individually detected using the time series light intensity data.
Abstract:
There is provided a way of enabling the discrimination or identification of the kind of a light-emitting particle corresponding to each pulse form signal in the scanning molecule counting method using the optical measurement by the confocal or multiphoton microscope. In the inventive technique, the position of a light detection region in a sample solution periodically along a predetermined route is moved in measuring the light intensity from the light detection region; and a signal of light from a light-emitting particle is detected individually. Then, an index value indicating a translational diffusional characteristic of one light-emitting particle in a plane perpendicular to the moving direction of the light detection region is determined based upon intensity values of signals of light of the same light-emitting particle for identifying a light-emitting particle.
Abstract:
The inventive technique of detecting and analyzing light from a light-emitting particle in accordance with the scanning molecule counting method using an optical measurement with a confocal microscope or a multiphoton microscope is characterized by detecting intensities of components of two or more wavelength bands of light from a light detection region of an optical system with moving the position of the light detection region in a sample solution by changing the optical path of the optical system of the microscope; detecting individually signals of the light from each light-emitting particle in the intensities of the components of the two or more wavelength bands of the detected light; and identifying a kind of light-emitting particle based on the intensities of the components of the two or more wavelength bands of the signals of the light of the detected light-emitting particle.
Abstract:
There is provided an optical analysis technique which observes a polarization characteristic of a light-emitting particle using the scanning molecule counting method using an optical measurement with a confocal microscope or a multiphoton microscope. In the inventive optical analysis technique, the light detection region is irradiated with excitation light consisting of predetermined polarized light component(s) and the intensity of at least one polarized light component of the light from the light detection region is detected with moving the position of the light detection region of the optical system in a sample solution; a signal of each light-emitting particle is detected individually in the intensity of at least one polarized light component; and based on the intensity of at least one polarized light component of the signal of the detected light-emitting particle, the polarization characteristic value of the light-emitting particle is computed.
Abstract:
There is provided an optical analysis technique of detecting light of a light-emitting particle in a sample solution in the scanning molecule counting method using the light measurement with a confocal or multiphoton microscope, for suppressing the scattering in detected results of signals of light of light-emitting particles smaller and achieving the improvement of accuracy. The inventive technique comprises moving the position of a light detection region along a predetermined route for multiple circulation times by changing the optical path of the optical system; detecting light from the light detection region and generating time series light intensity data during the moving of the light detection region and detecting individually a signal indicating light from each light-emitting particle existing in the predetermined route using the time series light intensity data obtained in the circulating movements of the light detection region of multiple times.
Abstract:
A method for detecting a fluorescent particle comprises the preparation of a sample solution containing fluorescent particles and a substance that promotes transition of the fluorescent particles from a triplet excited state to a singlet ground state, and calculation of the number of molecules of fluorescent particles present in the prepared sample solution. Calculation of the number of molecules of the fluorescent particles comprises moving the location of a photodetection region of an optical system in the sample solution using the optical system of a confocal microscope or multi-photon microscope, individually detecting fluorescent particles by detecting a light signal from the fluorescent particles present in the photodetection region while moving the location of the photodetection region in the sample solution, and counting the number of fluorescent particles detected during movement of the location of the photodetection region by counting the number of individually detected fluorescent particles.
Abstract:
There is provided a structure to reduce the size of light intensity data in the scanning molecule counting method using an optical measurement with a confocal microscope or a multiphoton microscope. In the inventive optical analysis technique of detecting light of a light-emitting particle in a sample solution, time series light intensity data of light from a light detection region detected with moving the position of the light detection region of the microscope in the sample solution is generated, and a signal of a light-emitting particle individually is detected in the time series light intensity data. In that case, regions where no signal indicating light of light-emitting particles exist in the time series light intensity data is removed from the time series light intensity data.
Abstract:
There is provided a method of measuring a diffusion characteristic value (for example, a diffusion constant) of a light-emitting particle using the scanning molecule counting method using the optical measurement with a confocal microscope or a multiphoton microscope. The inventive method of measuring a diffusion characteristic value of a light-emitting particle is characterized to measure light intensity from the light detection region with moving the position of the light detection region in the sample solution by changing an optical path of the optical system to generate light intensity data and to compute a diffusion characteristic value of the light-emitting particle based on a deviation time from a moving cycle time of the light detection region in an interval of generation times of two or more signals corresponding to a same light-emitting particle on the light intensity data.