title: Noninvasive time-dependent cytometry monitoring by digital holography.
abstract: Using a digital holographic microscope setup, it is possible to measure dynamic volume changes in living cells. The cells were investigated time-dependently in transmission mode for different kinds of stimuli affecting their morphology. The measured phase shift was correlated to the cellular optical thickness, and then of the cell volume as well as the refractive index were calculated and interpreted. For the characterization of the digital holographic microscope setup, we have developed a transparent three-dimensional (3-D) reference chart that can be used as a lateral resolution chart and step-height resolution chart included in one substrate. For the monitoring of living cells, a biocompatible and autoclavable flow chamber was designed, which allows us to add, exchange, or dilute the fluid within the flow chamber. An integrated changeable coverslip enables inverse microscopic applications. Trypsinization, cell swelling and shrinking induced by osmolarity changes, and apoptosis served as model processes to elucidate the potential of the digital holographic microscopy (DHM).
authors.affiliation: Fraunhofer Institute for Physical Measurement Techniques, Heidenhofstrasse 8, 79110 Freiburg, Germany.
authors.forename: Manuel
authors.initials: M
authors.lastname: Kemmler
authors.forename: Markus
authors.initials: M
authors.lastname: Fratz
authors.forename: Dominik
authors.initials: D
authors.lastname: Giel
authors.forename: Norbert
authors.initials: N
authors.lastname: Saum
authors.forename: Albrecht
authors.initials: A
authors.lastname: Brandenburg
authors.forename: Christian
authors.initials: C
authors.lastname: Hoffmann
mesh_terms: D000465:Algorithms; D000818:Animals; D017209:Apoptosis; D002460:Cell Line; D048429:Cell Size; D004867:Equipment Design; D005434:Flow Cytometry / Q000295:instrumentation / Q000379:methods* / Q000706:statistics & numerical data; D006696:Holography / Q000295:instrumentation / Q000379:methods* / Q000706:statistics & numerical data; D009836:Oligodendroglia / Q000166:cytology; D009994:Osmolar Concentration; D051381:Rats; D014357:Trypsin
chemical_list: D014357:Trypsin