Near-Field Nanoscopic Terahertz Imaging of Single Proteins.
Small
; 17(3): e2005814, 2021 01.
Article
em En
| MEDLINE
| ID: mdl-33306275
ABSTRACT
Terahertz (THz) biological imaging has attracted intense attention due to its capability of acquiring physicochemical information in a label-free, noninvasive, and nonionizing manner. However, extending THz imaging to the single-molecule level remains a challenge, partly due to the weak THz reflectivity of biomolecules with low dielectric constants. Here, the development of graphene-mediated THz scattering-type scanning near-field optical microscope for direct imaging of single proteins is reported. Importantly, it is found that a graphene substrate with high THz reflectivity and atomic flatness can provide high THz contrast against the protein molecules. In addition, a platinum probe with an optimized shaft length is found enabling the enhancement of the amplitude of the scattered THz near-field signals. By coupling these effects, the topographical and THz scattering images of individual immunoglobulin G (IgG) and ferritin molecules with the size of a few nanometers are obtained, simultaneously. The demonstrated strategy thus opens new routes to imaging single biomolecules with THz.
Palavras-chave
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Imagem Terahertz
/
Grafite
Idioma:
En
Revista:
Small
Assunto da revista:
ENGENHARIA BIOMEDICA
Ano de publicação:
2021
Tipo de documento:
Article
País de afiliação:
China