Colloidal probe technique

Scheme of the colloidal probe technique for direct force measurements in the sphere-plane and sphere-sphere geometries.

The colloidal probe technique is commonly used to measure interaction forces acting between colloidal particles and/or planar surfaces in air or in solution. This technique relies on the use of an atomic force microscope (AFM). However, instead of a cantilever with a sharp AFM tip, one uses the colloidal probe. The colloidal probe consists of a colloidal particle of few micrometers in diameter that is attached to an AFM cantilever. The colloidal probe technique can be used in the sphere-plane or sphere-sphere geometries (see figure). One typically achieves a force resolution between 1 and 100 pN and a distance resolution between 0.5 and 2 nm.

The colloidal probe technique has been developed in 1991 independently by Ducker[1] and Butt.[2] Since its development this tool has gained wide popularity in numerous research laboratories, and numerous reviews are available in the scientific literature.[3][4][5]

Alternative techniques to measure force between surfaces involve the surface forces apparatus, total internal reflection microscopy, and optical tweezers techniques to with video microscopy.

  1. ^ Ducker, William A.; Senden, Tim J.; Pashley, Richard M. (1991). "Direct measurement of colloidal forces using an atomic force microscope". Nature. 353 (6341): 239–241. Bibcode:1991Natur.353..239D. doi:10.1038/353239a0. ISSN 0028-0836. S2CID 4311419..
  2. ^ Butt, Hans-Jürgen (1991). "Measuring electrostatic, van der Waals, and hydration forces in electrolyte solutions with an atomic force microscope". Biophysical Journal. 60 (6): 1438–1444. Bibcode:1991BpJ....60.1438B. doi:10.1016/S0006-3495(91)82180-4. ISSN 0006-3495. PMC 1260203. PMID 19431815.
  3. ^ Butt, Hans-Jürgen; Cappella, Brunero; Kappl, Michael (2005). "Force measurements with the atomic force microscope: Technique, interpretation and applications". Surface Science Reports. 59 (1–6): 1–152. Bibcode:2005SurSR..59....1B. doi:10.1016/j.surfrep.2005.08.003. ISSN 0167-5729.
  4. ^ Ralston, John; Larson, Ian; Rutland, Mark W.; Feiler, Adam A.; Kleijn, Mieke (2005). "Atomic force microscopy and direct surface force measurements (IUPAC Technical Report)". Pure and Applied Chemistry. 77 (12): 2149–2170. doi:10.1351/pac200577122149. ISSN 1365-3075.
  5. ^ Borkovec, Michal; Szilagyi, Istvan; Popa, Ionel; Finessi, Marco; Sinha, Prashant; Maroni, Plinio; Papastavrou, Georg (2012). "Investigating forces between charged particles in the presence of oppositely charged polyelectrolytes with the multi-particle colloidal probe technique". Advances in Colloid and Interface Science. 179–182: 85–98. doi:10.1016/j.cis.2012.06.005. ISSN 0001-8686. PMID 22795487.