3 Springer Series on Fluorescence Methods and Applications Series Editor: O.S.Wolfbeis Fluorescence Spectroscopy in Biology Advanced Methods and their Applications to Membranes,Proteins,DNA,and Cells Volume Editors: M.Hof · R.Hutterer · V.Fidler 3 About this series: Fluorescence spectroscopy,fluorescence imaging and fluorescent probes are indispensible tools in numerous fields of modern medicine and science, including molecular biology,biophysics,biochemistry,clinical diagnosis and analytical and environmental chemistry.Applications stretch from spectro- scopy and sensor technology to microscopy and imaging,to single molecule detection,to the development of novel fluorescent probes,and to proteomics and genomics.The Springer Series on Fluorescence aims at publishing state- of-the-art articles that can serve as invaluable tools for both practitioners and researchers being active in this highly interdisciplinary field.The carefully edited collection of papers in each volume will give continuous inspiration for new research and will point to exciting new trends. Library of Congress Control Number:2004114543 ISSN 1617-1306 ISBN3-540-22338-XSpringer Berlin Heidelberg New York This work is subject to copyright.All rights are reserved,whether the whole or part of the material is concerned, specifically the rights of translation,reprinting,reuse of illustrations,recitation,broadcasting,reproduction on microfilm or in any other way,and storage in data banks.Duplication of this publication or parts thereof is per- mitted only under the provisions of the German Copyright Law of September 9,1965,in its current version,and permission for use must always be obtained from Springer-Verlag.Violations are liable for prosecution under the German Copyright Law. Springer is a part of Springer Science+Business Media springeronline.com © Springer-Verlag Berlin Heidelberg 2005 Printed in Germany The use of general descriptive names,registered names,trademarks,etc.in this publication does not imply,even in the absence of a specific statement,that such names are exempt from the relevant protective laws and regula- tions and therefore free for general use. Cover-design:design and production GmbH Dataconversion:Fotosatz-Service Köhler GmbH,Würzburg Printed on acid-free paper 52/3020xv – 5 4 3 2 1 0 Series Editor Professor Dr.Otto S.Wolfbeis University ofRegensburg Institute ofAnalytical Chemistry,Chemo- and Biosensors Universitätsstraße 31 93040 Regensburg Germany e-mail:[email protected] Volume Editors Professor M.Hof J.HeyrovskýInstitute ofPhysical Chemistry Academy ofSciences ofthe Czech Republic and Centre for Complex Molecular Systems and Biomolecules Dolejškova 3 18223 Prague 8 Czech Republic e-mail:[email protected] Professor R.Hutterer Institute ofAnalytical Chemistry,Chemo- and Biosensors Universitätsstraße 31 93040 Regensburg Germany e-mail:[email protected] Professor V.Fidler Faculty ofNuclear Sciences and Physical Engineering Czech Technical University in Prague Břehová 7 11519 Praha 1 Czech Republic e-mail:[email protected] Preface Take any combination ofthe following features:supramolecular structures with a specific fluorescent probe localized as you would like;nanoscale spatial resolu- tion;tailor-made molecular and/or solid-state fluorescing nanostructures;user- friendly and/or high- throughput fluorescence techniques;the ability to do what- ever you wish with just one single (supra)molecule;utilization ofnon-linear optical processes;and,last but not least,physical understanding ofthe processes result- ing in a (biological) functionality at the single molecule level.What you will then have is some recent progress in physics,chemistry,and the life sciences leading to the development of a new tool for research and application.This was amply demonstrated at the 8th Conference on Methods and Applications ofFluorescence: Probes,Imaging,and Spectroscopy held in Prague,the Czech Republic on August 24th–28th, 2003. This formed a crossroad of ideas from a variety of natural science and technical research fields and biomedical applications in particular. This volume – the third book in the Springer-Verlag Series on Fluorescence – reviews some of the most characteristic topics of the multidisciplinary area of fluorescence applications in life sciences either presendted directly at th 8th MAF Conference or considered to be a cruical development in the field. In the initial contribution in Part 1 – Basics and Advanced Approaches,the ed- itors explain the basics of fluorescence and illustrate the relationship between some modern fluorescence techniques and classical approaches. The second contrigution by B.Valeur,with his many years ofpersonal experience,helps the fluorescence spectroscopist to answer teh perennial question ofwhether to use pulse or phase modulation fluorescence detection.A technically demanding but promising new approach for extracting distance information from fluorescence kinetics data is presented by ist innovator L.Johansson in the third contribution. The three subsequent contributions also have the pioneers ofeach new approach among their authors:D.Birch – nanotomography,M.Hof – solvent relaxation used micro-polarity and fluidity probing, and N. Thompson – total internal reflection fluorescence microscopy.The last contribution in Part 1,written by J. Enderlein, is devoted to single molecule spectroscopy using a quantitative approach to data analysis in this important new experimental field.Part 2 – Fluo- rescence in Biological Membranes – addresses a hot topic in membrane research, i.e.,the formation ofmicrodomains.G.Duportail summarizes the recent results in the study oflipid rafts using fluorescence quenching and L.Bagatolli demon- strates the use offluorescence microscopy in the charcterization ofdomain for- mation. VIII Preface Part 3 consisting ofcontributions ten and eleven deals with advanced fluores- cene kinetics analysis in protein sciences.G.Krishnamoorthy’s chapter shows what we can learn with time-resolved fluorescence about protein dynamics and folding.Y.Mély combines time-resolved fluorescence with FCS to elucidate the mechnaism ofinteraction ofthe HIV-1 nucleocapsid protein with hairpin loop oligonucleotides. The development ofefficient non-viral dug carriers is one ofthe most urgently needed requirements in the biological sciences. It has become obvious that modern fluorescence is capable ofhelping in the development ofsuch supramol- ecular assemblies.Thus the two contributions (I.Blagbrough and M.Langner) in Part 4 are devoted to this field. The final part ofthis volume focuses on two new approaches in cell fluores- cence microscopy. R. Brock shows how to characterize diffusion in cells by fluorescence correlation spectroscopy.The last two contributions by S.Rosenthal and O.Minet are devoted to photophysics and the use of quantum dots in cell imaging. Prague,October 2004 Martin Hof,Rudi Hutterer,and Vlastimil Fidler Contents Part 1 Fluorescence Spectroscopy:Basics and Advanced Approaches . . . 1 1 Basics ofFluorescence Spectroscopy in Biosciences . . . . . . . . 3 M.Hof,V.Fidler andR.Hutterer 1.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 1.2 Fluorescence and its Measurement . . . . . . . . . . . . . . . . . 4 1.2.1 Molecular Electronic Relaxation . . . . . . . . . . . . . . . . . . 4 1.2.2 Detecting Fluorescence . . . . . . . . . . . . . . . . . . . . . . . 5 1.2.3 Data Evaluation . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 1.3 Polarized Fluorescence . . . . . . . . . . . . . . . . . . . . . . . 7 1.3.1 Definition ofPolarization and Anisotropy . . . . . . . . . . . . . 7 1.3.2 Steady-State Fluorescence Anisotropy . . . . . . . . . . . . . . . 8 1.3.3 Time-Resolved Fluorescence Polarization . . . . . . . . . . . . . 9 1.3.3.1 Non-Spherical Particles in Homogenous Isotropic Medium . . . . 9 1.3.3.2 Segmental Mobility ofthe Chromophore . . . . . . . . . . . . . . 10 1.3.3.3 Hindered Rotors:Fluorescent Dyes in Biological Membranes . . . 10 1.4 Influence ofFluorescence Quenching . . . . . . . . . . . . . . . . 11 1.4.1 Fluorescence Quantum Yield and Lifetime . . . . . . . . . . . . . 11 1.4.2 Fluorescence Quenchers . . . . . . . . . . . . . . . . . . . . . . . 11 1.4.2.1 Solute Quenching . . . . . . . . . . . . . . . . . . . . . . . . . . 12 1.4.2.2 Solute Quenching in Protein Studies:an Application Example . . 13 1.4.2.3 Solvent Quenching . . . . . . . . . . . . . . . . . . . . . . . . . . 15 1.4.2.4 Self-Quenching . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16 1.4.2.5 Trivial Quenching . . . . . . . . . . . . . . . . . . . . . . . . . . 16 1.5 Influence ofSolvent Relaxation on Solute Fluorescence . . . . . . 17 1.5.1 Basics ofSolvent Relaxation . . . . . . . . . . . . . . . . . . . . . 17 1.5.2 Influence ofSolvent Relaxation on Steady-State Spectra . . . . . . 18 1.5.2.1 Non-Viscous Solvents . . . . . . . . . . . . . . . . . . . . . . . . 18 1.5.2.2 Viscous and Vitrified Solutions . . . . . . . . . . . . . . . . . . . 18 1.5.3 Quantitative Characterization ofSolvent Relaxation by Time-Resolved Spectroscopy . . . . . . . . . . . . . . . . . . . 19 1.6 Fluorescence Resonance Energy Transfer as a Spectroscopic Ruler . . . . . . . . . . . . . . . . . . . . . . 20 1.6.1 Donor-Acceptor Pairs at Fixed Distances . . . . . . . . . . . . . 20 1.6.2 Donor-Acceptor Pairs at Variable Distances . . . . . . . . . . . 21 1.6.3 Some Applications ofFluorescence Resonance Energy Transfer 21 1.7 Irreversible Photobleaching . . . . . . . . . . . . . . . . . . . . 22 X Contents 1.8 Single Molecule Fluorescence . . . . . . . . . . . . . . . . . . . 23 1.9 Optical Sensors Based on Fluorescence . . . . . . . . . . . . . . 24 References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25 2 Pulse and Phase Fluorometries:An Objective Comparison . . . . 30 B.Valeur 2.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30 2.2 General Principles ofTime-Resolved Fluorometry . . . . . . . . . 31 2.2.1 Pulse Fluorometry . . . . . . . . . . . . . . . . . . . . . . . . . . 32 2.2.2 Phase-Modulation Fluorometry . . . . . . . . . . . . . . . . . . . 32 2.2.3 Relation Between Harmonic Response andd-Pulse Response . . . 33 2.2.4 General Relations for Single Exponential and Multiexponential Decays . . . . . . . . . . . . . . . . . . . . 34 2.3 Pulse Fluorometers . . . . . . . . . . . . . . . . . . . . . . . . . . 35 2.4 Phase-Modulation Fluorometers . . . . . . . . . . . . . . . . . . 37 2.4.1 Phase Fluorometers Using a Continuous Light Source and an Optical Modulator . . . . . . . . . . . . . . . . . . . . . . 38 2.4.2 Phase Fluorometers Using the Harmonic Content ofa Pulsed Laser . . . . . . . . . . . . . . . . . . . . . . . . . . . 40 2.5 Data Analysis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41 2.6 Specific Applications . . . . . . . . . . . . . . . . . . . . . . . . . 42 2.6.1 Time-Resolved Spectra . . . . . . . . . . . . . . . . . . . . . . . . 42 2.6.2 Time-Resolved Emission Anisotropy . . . . . . . . . . . . . . . . 44 2.6.3 Lifetime-Based Decomposition ofSpectra . . . . . . . . . . . . . 45 2.6.4 Fluorescence Lifetime Imaging Microscopy (FLIM) . . . . . . . . 45 2.7 Concluding Remarks . . . . . . . . . . . . . . . . . . . . . . . . . 47 References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48 3 Non-Exponential Fluorescence ofElectronically Coupled Donors Contains Distance Information . . . . . . . . . . . . . . 49 S.Kalinin,M.Isaksson andL.B.-Å.Johansson 3.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49 3.2 Theory . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50 3.3 Methods . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51 3.4 Results and Discussion . . . . . . . . . . . . . . . . . . . . . . . 51 3.4.1 Synthetic Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51 3.4.2 Experimental Data . . . . . . . . . . . . . . . . . . . . . . . . . . 53 3.5 Conclusions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 54 References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 54 Contents XI 4 Fluorescence Nanotomography:Recent Progress,Constraints and Opportunities . . . . . . . . . . . . . . . . . . . . . . . . . . 56 O.J.Rolinski andD.J.S.Birch 4.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 56 4.2 Fluorescence Resonance Energy Transfer . . . . . . . . . . . . . . 57 4.3 FRET Sensors . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58 4.4 Fluorescence Nanotomography Theory . . . . . . . . . . . . . . . 60 4.4.1 An Inverse Problem . . . . . . . . . . . . . . . . . . . . . . . . . 61 4.4.2 Separation ofVariables Approach . . . . . . . . . . . . . . . . . . 62 4.4.3 Numerical Simulations . . . . . . . . . . . . . . . . . . . . . . . 64 4.5 Experimental . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 66 4.5.1 Bulk Solutions . . . . . . . . . . . . . . . . . . . . . . . . . . . . 66 4.5.2 Porous Polymer Nafion117 . . . . . . . . . . . . . . . . . . . . . 66 4.5.3 Phospholipid Bilayers . . . . . . . . . . . . . . . . . . . . . . . . 68 4.6 Conclusions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69 References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69 5 Solvent Relaxation as a Tool for Probing Micro-Polarity and -Fluidity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 71 J.Sy´kora,R.Hutterer andM.Hof 5.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 71 5.2 Basic Principles ofthe SR Method . . . . . . . . . . . . . . . . . 71 5.3 Applications ofthe SR Technique by Using Time-Correlated Single Photon Counting . . . . . . . . . . . . . . . . . . . . . . . 73 5.3.1 SR in Phospholipid Bilayers . . . . . . . . . . . . . . . . . . . . . 73 5.3.2 SR in Reverse Micelles . . . . . . . . . . . . . . . . . . . . . . . . 75 5.3.3 SR in Polymers . . . . . . . . . . . . . . . . . . . . . . . . . . . . 76 5.3.4 SR in Ionic Liquid . . . . . . . . . . . . . . . . . . . . . . . . . . 76 5.3.5 SR in DNA . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 76 5.3.6 SR in Proteins . . . . . . . . . . . . . . . . . . . . . . . . . . . . 77 References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 77 6 Total Internal Reflection Fluorescence Microscopy: Applications in Biophysics . . . . . . . . . . . . . . . . . . . . . 79 N.L.Thompson andJ.K.Pero 6.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 79 6.1.1 Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 79 6.1.2 Optical Principles . . . . . . . . . . . . . . . . . . . . . . . . . . 79 6.1.3 Apparatus . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 81 6.1.4 Sample Types . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 83 6.2 Combination ofTIRFM with Other Methods . . . . . . . . . . . . 83 6.2.1 Fluorescence Recovery after Photobleaching . . . . . . . . . . . . 83 XII Contents 6.2.2 Evanescent Interference Patterns . . . . . . . . . . . . . . . . . . 85 6.2.3 Fluorescence Correlation Spectroscopy . . . . . . . . . . . . . . . 86 6.2.4 Fluorescence Resonance Energy Transfer . . . . . . . . . . . . . . 88 6.2.5 Variable Incidence Angles . . . . . . . . . . . . . . . . . . . . . . 89 6.2.6 Inverse Imaging . . . . . . . . . . . . . . . . . . . . . . . . . . . 90 6.3 Advanced Topics . . . . . . . . . . . . . . . . . . . . . . . . . . . 91 6.3.1 High Refractive Index Substrates . . . . . . . . . . . . . . . . . . 91 6.3.2 Thin Metal Films and Metallic Nanostructures . . . . . . . . . . . 92 6.3.3 Fluorescence Emission Near Planar Dielectric Interfaces . . . . . 92 6.3.4 Fluorescence Polarization . . . . . . . . . . . . . . . . . . . . . . 93 6.3.5 Fluorescence Lifetimes and Time-Resolved Anisotropies . . . . . 94 6.3.6 Two-Photon Excitation . . . . . . . . . . . . . . . . . . . . . . . 94 6.4 Other Applications . . . . . . . . . . . . . . . . . . . . . . . . . . 95 6.4.1 Single Molecule Imaging . . . . . . . . . . . . . . . . . . . . . . 95 6.4.2 Imaging Cell–Substrate Contact Regions . . . . . . . . . . . . . . 96 6.4.3 Exocytosis and Secretion Vesicle Dynamics . . . . . . . . . . . . 97 6.4.4 Emerging Methods . . . . . . . . . . . . . . . . . . . . . . . . . . 98 6.5 Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 98 References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 99 7 Single Molecule Spectroscopy:Basics and Applications . . . . . . 104 J.Enderlein 7.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 104 7.2 Photophysics,Probes and Markers . . . . . . . . . . . . . . . . . 105 7.3 Physical Techniques . . . . . . . . . . . . . . . . . . . . . . . . . 109 7.3.1 Modified Flow Cytometry,Microchannels and Microdroplets . . . 109 7.3.2 Confocal Detection . . . . . . . . . . . . . . . . . . . . . . . . . 111 7.3.3 Wide-Field Imaging . . . . . . . . . . . . . . . . . . . . . . . . . 113 7.4 Data Acquisition and Evaluation . . . . . . . . . . . . . . . . . . 116 7.4.1 Time-Tagged and Time-Correlated Photon Counting . . . . . . . 116 7.4.2 Fluorescence Correlation Spectroscop . . . . . . . . . . . . . . . 117 7.4.3 Fluorescence Intensity Distribution Analysis and Related Techniques . . . . . . . . . . . . . . . . . . . . . . . 120 7.4.4 Molecule-by-Molecule Analysis . . . . . . . . . . . . . . . . . . . 120 References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 122 Part 2 Application of Fluorescence Spectroscopy to Biological Membranes 131 8 Raft Microdomains in Model Membranes as Revealed by Fluorescence Quenching . . . . . . . . . . . . . . . . . . . . . 133 G.Duportail 8.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 133 8.2 Identification ofLipid Compositions Forming Rafts . . . . . . . . 134