title: Force microscopy analysis using chemometric tools.
abstract: In this paper we report the first application of multivariate data analysis techniques to force spectrometry measurement sets to enable the physicochemical assignment of spatially ordered multi-component systems. Principal component analysis (PCA) and hierarchical clustering techniques were used to reveal hidden chemical information within force-distance curves generated by high spatial resolution force microscopy. Two experimental samples were analyzed: (i) a two-component system of cytochrome c proteins on a mica surface, and (ii) a three-component system of avidin protein islands positioned on a gold and glass surface. PCA and hierarchical clustering techniques were used to discriminate the different components of the two-component system, whereas hierarchical clustering was found to be superior for the three-component system. Results were in good agreement with the topography and prior knowledge of the surface patterns. This research represents a formative step towards the combination of force spectrometry with chemometric tools for the high resolution physicochemical investigation of complex biochemical systems.
authors.affiliation: Institute for Analytical Sciences, Bunsen-Kirchhoff-Str. 11, 44139, Dortmund, Germany.
authors.forename: Christian
authors.initials: C
authors.lastname: Budich
authors.forename: Jonathan
authors.initials: J
authors.lastname: West
authors.forename: Peter
authors.initials: P
authors.lastname: Lampen
authors.forename: Volker
authors.initials: V
authors.lastname: Deckert
mesh_terms: D000268:Adhesiveness; D016000:Cluster Analysis; D045304:Cytochromes c / Q000648:ultrastructure; D018625:Microscopy, Atomic Force / Q000379:methods*
chemical_list: D045304:Cytochromes c