Scattering microscopy

Patent metadata

Field	Value
Publication number	US-2022221401-A1
Application number	US-202017440945-A
Country	US
Kind code	A1
Filing date	Mar 12, 2020
Priority date	Mar 21, 2019
Publication date	Jul 14, 2022
Grant date	—

Abstract

A scattering microscopy arrangement uses a microscope to image an object comprising a surface. A light source emits illuminating light and a light detector detects light elastically scattered from the object. An electrical potential is applied to the surface that affects the electrochemical properties of the object while imaging The electrical potential provides a contrast mechanism that improves the imaging and allows for characterisation of the object and/or the surrounding environment.

First claim

1 . A method of performing scattering microscopy,
the method comprising imaging an object comprising a surface with a scattering microscope including a light source arranged to emit illuminating light and a light detector, the microscope being arranged to illuminate an object with the illuminating light and to detect light elastically scattered from the object with the light detector, the method further comprising applying an electrical potential to the surface that affects the electrochemical properties of the object while imaging the object, the object being selected not to have a plasmon resonance frequency at the wavelengths of the illuminating light and at the applied electrical potential.

2 . A method according to claim 1 , wherein an electric double layer forms at the object and the electrical potential to the surface affects the electrochemical properties of the electric double layer.

3 . A method according to claim 1 , wherein the surface is a surface of a conductive material and the step of applying an electric potential to the surface comprises applying the potential to the conductive material.

4 . A method according to claim 3 , wherein the conductive material is not a metal.

5 . A method according to claim 1 , wherein the surface is a surface of a dielectric material and the step of applying an electric potential to the surface comprises applying the potential capacitively through the dielectric material.

6 . A method according to claim 1 , wherein the object further comprises at least one particle on the surface.

7 . A method according to claim 6 , wherein the at least one particle has a mass of 5000 kDa or less.

8 . A method according to claim 6 , wherein the at least one particle has a mass of 10 kDa or more.

9 . A method according to claim 7 , wherein the at least one particle has a scattering cross section with respect to the illuminating light of 10 −17 m 2 or less.

10 . A method according to claim 7 , wherein the at least one particle has a scattering cross section with respect to the illuminating light of 10 −26 m 2 or more.

11 . A method according to claim 1 , wherein the electrical potential has an amplitude that is constant over a response period of the electrochemical properties of the object that are affected thereby.

12 . A method according to claim 1 , wherein the electrical potential has an amplitude that changes over a period less than the response period of the electrochemical properties of the object that are affected thereby.

13 . A method according to claim 12 , wherein the electrical potential has an amplitude that is alternating over a period less than the response period of the electrochemical properties of the object that are affected thereby.

14 . A method according to claim 1 , wherein the method comprises applying plural different electrical potentials to the surface, and detecting the light elastically scattered from a part of the object in respect of each electrical potential for characterisation of that part of the object and/or the surrounding environment.

15 . A method according to claim 14 , further comprising determining the degree of similarity of the profile of the light elastically scattered from a part of the object in respect of each electrical potential with a reference profile.

16 . A method according to claim 1 , wherein the microscope is arranged so that the signal detected by the light detector is sensitive to the amplitude of the light elastically scattered from the object.

17 . A method according to claim 1 , wherein the microscope is an interferometric scattering microscope or a dark field scattering microscope.

18 . A method according to claim 1 , wherein the microscope is arranged to output a two-dimensional image of the object.

19 . A method according to claim 1 , wherein the light is ultraviolet light, visible light, or infrared light.

20 . A scattering microscopy arrangement, the microscopy arrangement comprising:
an object comprising a surface; a microscope including a light source arranged to emit illuminating light and a light detector, the microscope being arranged to illuminate the object with the illuminating light and to detect with the light detector light elastically scattered from the object; and a voltage source arranged to apply an electrical potential to the surface that affects the electrochemical properties of the object while imaging the object, the object being selected not to have a plasmon resonance frequency at the wavelengths of the illuminating light and at the applied electrical potential.

Assignees

• Univ Oxford Innovation Ltd

Inventors

• Kukura Philipp
• Faez Sanli

Classifications

• G02B21/361

  Optical details, e.g. image relay to the camera or image sensor (G02B21/364 takes precedence; illumination details G02B21/06 and subgroups) · CPC title

• G02B21/002

  Scanning microscopes (scanning near field optical microscopes G01Q60/18) · CPC title

• G02B21/06 Primary

  Means for illuminating specimens · CPC title

• G01N21/66

  electrically excited, e.g. electroluminescence · CPC title

• G01N21/4795 Primary

  spatially resolved investigating of object in scattering medium (in vivo A61B) · CPC title