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Updated: Jul 14, 2026

Covalent Attachment of Single Molecules for AFM-based Force Spectroscopy
Published on: March 16, 2020
Direct measurements of the interaction between pyrene and graphite in aqueous media by single molecule force
Yiheng Zhang1, Chuanjun Liu, Weiqing Shi
1Key Lab of Organic Optoelectronics and Molecular Engineering, Department of Chemistry, Tsinghua University, Beijing 100084, P. R. China.
Abstract:
Pyrene derivatives can absorb onto the surface of carbon nanotubes and graphite particles through pi-pi interactions to functionalize these inorganic building blocks with organic surface moieties. Using single molecule force spectroscopy, we have demonstrated the first direct measurement of the interaction between pyrene and a graphite surface. In particular, we have connected a pyrene molecule onto an AFM tip via a flexible poly(ethylene glycol) (PEG) chain to ensure the formation of a molecular bridge. The pi-pi interaction between pyrene and graphite is thus indicated to be approximately 55 pN with no hysteresis between the desorption and adhesion forces.

