title: Micro-rheology on (polymer-grafted) colloids using optical tweezers.
abstract: Optical tweezers are experimental tools with extraordinary resolution in positioning (± 1 nm) a micron-sized colloid and in the measurement of forces (± 50 fN) acting on it-without any mechanical contact. This enables one to carry out a multitude of novel experiments in nano- and microfluidics, of which the following will be presented in this review: (i) forces within single pairs of colloids in media of varying concentration and valency of the surrounding ionic solution, (ii) measurements of the electrophoretic mobility of single colloids in different solvents (concentration, valency of the ionic solution and pH), (iii) similar experiments as in (i) with DNA-grafted colloids, (iv) the nonlinear response of single DNA-grafted colloids in shear flow and (v) the drag force on single colloids pulled through a polymer solution. The experiments will be described in detail and their analysis discussed.
authors.affiliation: Institute of Experimental Physics I, Leipzig University, Linnéstrasse 5, D-04103, Leipzig, Germany.
authors.forename: C
authors.initials: C
authors.lastname: Gutsche
authors.forename: M M
authors.initials: MM
authors.lastname: Elmahdy
authors.forename: K
authors.initials: K
authors.lastname: Kegler
authors.forename: I
authors.initials: I
authors.lastname: Semenov
authors.forename: T
authors.initials: T
authors.lastname: Stangner
authors.forename: O
authors.initials: O
authors.lastname: Otto
authors.forename: O
authors.initials: O
authors.lastname: Ueberschär
authors.forename: U F
authors.initials: UF
authors.lastname: Keyser
authors.forename: M
authors.initials: M
authors.lastname: Krueger
authors.forename: M
authors.initials: M
authors.lastname: Rauscher
authors.forename: R
authors.initials: R
authors.lastname: Weeber
authors.forename: J
authors.initials: J
authors.lastname: Harting
authors.forename: Y W
authors.initials: YW
authors.lastname: Kim
authors.forename: V
authors.initials: V
authors.lastname: Lobaskin
authors.forename: R R
authors.initials: RR
authors.lastname: Netz
authors.forename: F
authors.initials: F
authors.lastname: Kremer
mesh_terms: D001703:Biophysics / Q000379:methods*; D003102:Colloids / Q000737:chemistry*; D004247:DNA / Q000737:chemistry*; D004573:Electrolytes; D006863:Hydrogen-Ion Concentration; D007477:Ions; D018715:Microscopy, Video / Q000379:methods; D016011:Normal Distribution; D052898:Optical Tweezers; D011108:Polymers / Q000737:chemistry*; D012212:Rheology
chemical_list: D003102:Colloids; D004573:Electrolytes; D007477:Ions; D011108:Polymers; D004247:DNA