Detection method for single nanoparticle

Abstract

The invention relates to a detection method for a single nanoparticle. The detection method comprises the following steps: allowing a single nanoparticle to be adhered onto a coverslip; subjecting light emitted by a light source to beam expanding and shaping and then allowing light to be focused on the rear focal plane of an oil-immersion object lens; adjusting the position of incident light on the rear focal plane of an oil-immersion object lens to allow the incident light obliquely entering the coverslip, thereby producing on the surface of the coverslip evanescent waves which are propagatedalong the surface and exponentially damps in intensity along a vertical direction; allowing the evanescent waves to encounter with the single nanoparticle and thus to undergo scattering, thereby producing radial interface scattering as the evanescent waves are propagated along the surface of the coverslip; and collecting the signals of the interface scattering and reflected light on the coverslipin virtue of CCD and carrying out imaging on the single nanoparticle by using the CCD. The detection method is low in cost, stable in detection performance, fast in detection speed, high in sensitivity, suitable for in-situ and portable detection and further applicable to virus detection, detection of nanometer pollutants in the atmosphere and the like.

Description

technical field [0001] The invention relates to the technical field of microscopic imaging detection, in particular to a detection method for a single nano particle. Background technique [0002] In recent years, with the development of nano, material, and optical technologies, nanoscale microscopic imaging has been widely used in life sciences, biochemistry, materials science, etc. and other fields. [0003] Among the currently widely used imaging technologies, ordinary optical microscopes are limited by the diffraction limit and have low resolution, so they cannot detect substances with a size smaller than 200nm. Electron microscopy, including transmission electron microscopy (TEM) and scanning electron microscopy (SEM), can improve resolution to the nanometer level. However, electron microscopy requires a vacuum operating environment, high equipment costs, generally requires sample pretreatment, and cannot perform biological sample detection, thus limiting its applicati...

AI Technical Summary

Problems solved by technology

[0005] The purpose of the present invention is to provide a detection method for a single nanoparticle, which can perform label-free and fast imaging detection on a single nanoparticle, which solves the deficiency that the optical microscope cannot image nanomaterials in the prior art, and also compensates for the electronic The shortcomings of traditional nano-microscopic instruments such as microscopes, such as long detection time, high cost, and vacuum operation, also make up for the imaging problems caused by the fluorescence bleaching effect of total internal reflection fluorescence microscopy.

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