title: Single cell viability and impact of heating by laser absorption.
abstract: Optical traps such as tweezers and stretchers are widely used to probe the mechanical properties of cells. Beyond their large range of applications, the use of infrared laser light in optical traps causes significant heating effects in the cell. This study investigated the effect of laser-induced heating on cell viability. Common viability assays are not very sensitive to damages caused in short periods of time or are not practicable for single cell analysis. We used cell spreading, a vital ability of cells, as a new sensitive viability marker. The optical stretcher, a two beam laser trap, was used to simulate heat shocks that cells typically experience during measurements in optical traps. The results show that about 60% of the cells survived heat shocks without vital damage at temperatures of up to 58 ± 2°C for 0.5 s. By varying the duration of the heat shocks, it was shown that 60% of the cells stayed viable when exposed to 48 ± 2°C for 5 s.
authors.affiliation: Department of Physics and Earth Science, Soft Matter Physics Division, Institute of Experimental Physics I, University of Leipzig, Linnéstrasse 5, 04103 Leipzig, Germany. franziska.wetzel@uni-leipzig.de
authors.forename: Franziska
authors.initials: F
authors.lastname: Wetzel
authors.forename: Susanne
authors.initials: S
authors.lastname: Rönicke
authors.forename: Karla
authors.initials: K
authors.lastname: Müller
authors.forename: Markus
authors.initials: M
authors.lastname: Gyger
authors.forename: Daniel
authors.initials: D
authors.lastname: Rose
authors.forename: Mareike
authors.initials: M
authors.lastname: Zink
authors.forename: Josef
authors.initials: J
authors.lastname: Käs
mesh_terms: D000042:Absorption; D000818:Animals; D048429:Cell Size / Q000528:radiation effects; D002470:Cell Survival / Q000528:radiation effects; D018869:Heat-Shock Response / Q000528:radiation effects; D006358:Hot Temperature / Q000009:adverse effects*; D007834:Lasers / Q000009:adverse effects*; D051379:Mice; D041681:NIH 3T3 Cells; D059010:Single-Cell Analysis