AFM-Tip Functionalization for Single Molecule Recognition Imaging
نویسندگان
چکیده
The high force sensitivity of the atomic force microscope (AFM) has opened the possibility of measuring interand intramolecular forces of biomolecules on the single molecule level. Covalent binding of bioligands to AFM tips converts them into monomolecular biosensors by which cognate receptors can be localized on the sample surface and fine details of ligand-receptor interaction can be studied. Tethering of the bioligand to the AFM tip via a ~6 nm long, flexible poly(ethylene glycol) linker (PEG) allows the bioligand to freely reorient and to rapidly ‘scan’ a large surface area while the tip is at or near the sample surface. Using suchlike modified AFM tips, a recent technology development lead to molecular recognition imaging, where topography and recognition sites are simultaneously localized with nanometer accuracy. Thus, the AFM can identify specific components on complex biological sample and retain its high resolution in imaging.
منابع مشابه
Versatile method for AFM-tip functionalization with biomolecules: fishing a ligand by means of an in situ click reaction.
A facile and universal method for the functionalization of an AFM tip has been developed for chemical force spectroscopy (CFS) studies of intermolecular interactions of biomolecules. A click reaction between tripod-acetylene and an azide-linker-ligand molecule was successfully carried out on the AFM tip surface and used for the CFS study of ligand-receptor interactions.
متن کاملSubmolecular Imaging by Noncontact Atomic Force Microscopy with an Oxygen Atom Rigidly Connected to a Metallic Probe.
In scanning probe microscopy, the imaging characteristics in the various interaction channels crucially depend on the chemical termination of the probe tip. Here we analyze the contrast signatures of an oxygen-terminated copper tip with a tetrahedral configuration of the covalently bound terminal O atom. Supported by first-principles calculations we show how this tip termination can be identifi...
متن کاملApplication Note #130 Common Approaches to Tip Functionalization for AFM-Based Molecular Recognition Measurements
technique, atomic force microscopy (AFM) is also uniquely well suited to measuring force interactions at the piconewton and nanonewton scale. This capability has been widely used to measure the nanomechanical properties of materials ranging from polymers to living cells and even to characterize single molecules. These measurements are normally made using common, unmodified AFM probes. However, ...
متن کاملAtomic force microscopy investigation of the morphology and the biological activity of protein-modified surfaces for bio- and immunosensors.
With the purpose of developing biosensors, the reliable proof of the biological activity of two new sensor systems was obtained by atomic force microscopy (AFM) in both the imaging and the single-molecule force spectroscopy modes. Antigens or antibodies of pharmacological interest were grafted onto self-assembled monolayers of thiols on gold, and AFM imaging demonstrated that the grafting proce...
متن کاملInteraction of scanning probes with semiconductor nanocrystals; physical mechanism and basis for near-field optical imaging.
We investigate the modification of photoluminescence (PL) from single semiconductor nanocrystal quantum dots (NCs) in the proximity of metal and semiconducting atomic force microscope (AFM) tips. The presence of the tip alters the radiative decay rate of an emitter via interference and opens efficient nonradiative decay channels via energy transfer to the tip material. These effects cause quenc...
متن کامل