This document introduces the use of AFM probes as chemically selective biosensors with affinity probes. By attaching ligand molecules to the tips of the probes, AFM probes can be transformed into sensitive, chemically selective biosensors.
This document details a protocol for transforming AFM probes into sensitive biosensors by attaching ligand molecules, specifically antibodies, to the probe tips. The technique relies on single-molecule molecular recognition force microscopy (MRFM) and topography and recognition imaging (TREC). The protocol focuses on using the heterobifunctional PEG linker NHS-PEG18-PDP to conjugate antibodies that have been activated with sulfhydryl groups.
| Antibody Molecular Weight | approximately 150 kDa |
|---|---|
| SATP to Protein Molar Ratio | 10:1 |
| Sulfhydryl Groups Yield | four to five per mole |
| Incubation Time | 30 minutes |
| UV-ozone Exposure Time | 1 hour |
The protocol uses the heterobifunctional PEG linker NHS-PEG18-PDP.
Antibodies are activated with the SATP reagent to introduce sulfhydryl groups.