BEGIN:VCALENDAR
VERSION:2.0
PRODID:-//Memento EPFL//
BEGIN:VEVENT
SUMMARY:Counting by Photon Statistics - Fluorescence Quantification based 
 on Photon Antibunching
DTSTART:20160318T140000
DTSTAMP:20260407T101152Z
UID:147e6200c09cc8efd17b417130aa3577bd1259ad2d226da3d9b993e0
CATEGORIES:Conferences - Seminars
DESCRIPTION:Dr. Kristin S. Grußmayer\, Heidelberg University (D)\nBIOENGI
 NEERING SEMINARAbstract:\nQuantitative information is key to unravel molec
 ular processes in all fields of research. Counting by Photon Statistics (C
 oPS) is a single molecule technique that provides such quantification for 
 fluorescent species. CoPS exploits the photon antibunching effect\, i.e. a
  dye as a quantum system may emit at most one photon per laser excitation 
 cycle. The simultaneous detection of multiple photons in a four-detector c
 onfocal microscope enables the estimation of the number of independent emi
 tters and their molecular brightness [1\,2]. Since the method is directly 
 based on the measured photon statistics\, it does not require calibration.
 \nUsing both simulations and experiments with defined\, DNA-based probes\,
  we analyzed the critical interplay of fluorophore properties and analysis
  parameters to achieve reliable quantification. We discovered that the tim
 e resolution can be up to ~10ms at high molecular brightness\, which opens
  new possibilities for time resolved measurements. The findings stress tha
 t the choice of analysis parameters is vital and provide a practical guide
 line to choose suitable dyes.\nWe show that CoPS is feasible with many flu
 orophores in different applications. In the biological context\, we invest
 igated the label number distribution of several commonly used fluorescent 
 markers\, e.g.\, SNAP-tag and nanobodies\, a prerequisite for quantitative
  investigations in cells [3]. Moreover\, we show that CoPS offers new pers
 pectives for characterization of photophysical processes in photoluminesce
 nt materials. We studied the behavior of conjugated polymers\, materials i
 mportant for organic semiconductor devices like polymer solar cells. Time-
 resolved CoPS measurements revealed heterogeneous dynamics in polymer chai
 n photophysics [4].\n[1] H. Ta\, J. Wolfrum\, and D.-P. Herten\, Laser Phy
 sics 2010\, 20\, 119–124\n[2] K. S. Grußmayer and D.–P. Herten\, in A
 dvanced Photon Counting\, (Eds.: P. Kapusta\, M. Wahl\, R. Erdmann)\, Spri
 nger International Publishing\, Cham\, Apr. 2015\, pp. 159–190\n[3] K. S
 . Grußmayer\, A. Kurz\, D.–P. Herten\, ChemPhysChem Feb. 2014\, 15\, 73
 4–742\n[4] K. S. Grußmayer\, F. Steiner\, J. M. Lupton\, D.–P. Herten
 \, and J. Vogelsang\, ChemPhysChem Dec. 2015\, 16\, 3578–3583
LOCATION:AI 1 153 http://map.epfl.ch/?room=ai1153
STATUS:CONFIRMED
END:VEVENT
END:VCALENDAR