1
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Xu Y, Sun L, Ghiggino KP, Smith TA. Resolving conjugated polymer film morphology with polarised transmission and time-resolved emission microscopy. Methods Appl Fluoresc 2024; 12:035004. [PMID: 38537297 DOI: 10.1088/2050-6120/ad388f] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2023] [Accepted: 03/27/2024] [Indexed: 04/17/2024]
Abstract
The alignment of chromophores plays a crucial role in determining the optoelectronic properties of materials. Such alignment can make interpretation of fluorescence anisotropy microscopy (FAM) images somewhat ambiguous. The time-resolved emission behaviour can also influence the fluorescence anisotropy. This is particularly the case when probing excitation energy migration between chromophores in a condensed phase. Ideally information concerning the chromophoric alignment, emission decay kinetics and fluorescence anisotropy can be recorded and correlated. We report on the use of polarised transmission imaging (PTI) coupled with both steady-state and time-resolved FAM to enable accurate identification of chromophoric alignment and morphology in thin films of a conjugated polydiarylfluorene. We show that the combination of these three imaging modes presents a comprehensive methodology for investigating the alignment and morphology of chromophores in thin films, particularly for accurately mapping the distribution of amorphous and crystalline phases within the thin films, offering valuable insights for the design and optimization of materials with enhanced optoelectronic performance.
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Affiliation(s)
- Yang Xu
- Ultrafast and Microspectroscopy Laboratories, School of Chemistry, University of Melbourne, Parkville, Victoria 3010, Australia
- ARC Centre of Excellence in Exciton Science, School of Chemistry, University of Melbourne, Parkville, Victoria 3010, Australia
| | - Lili Sun
- Centre for Supramolecular Optoelectronics (CSO), School of Flexible Electronics (Future Technologies) and Institute of Advanced Materials (IAM), Nanjing Tech University (NanjingTech), Nanjing 211816, People's Republic of China
| | - Kenneth P Ghiggino
- Ultrafast and Microspectroscopy Laboratories, School of Chemistry, University of Melbourne, Parkville, Victoria 3010, Australia
- ARC Centre of Excellence in Exciton Science, School of Chemistry, University of Melbourne, Parkville, Victoria 3010, Australia
| | - Trevor A Smith
- Ultrafast and Microspectroscopy Laboratories, School of Chemistry, University of Melbourne, Parkville, Victoria 3010, Australia
- ARC Centre of Excellence in Exciton Science, School of Chemistry, University of Melbourne, Parkville, Victoria 3010, Australia
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2
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Blacker TS, Duchen MR, Bain AJ. NAD(P)H binding configurations revealed by time-resolved fluorescence and two-photon absorption. Biophys J 2023; 122:1240-1253. [PMID: 36793214 PMCID: PMC10111271 DOI: 10.1016/j.bpj.2023.02.014] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2022] [Revised: 09/07/2022] [Accepted: 02/10/2023] [Indexed: 02/16/2023] Open
Abstract
NADH and NADPH play key roles in the regulation of metabolism. Their endogenous fluorescence is sensitive to enzyme binding, allowing changes in cellular metabolic state to be determined using fluorescence lifetime imaging microscopy (FLIM). However, to fully uncover the underlying biochemistry, the relationships between their fluorescence and binding dynamics require greater understanding. Here we accomplish this through time- and polarization-resolved fluorescence and polarized two-photon absorption measurements. Two lifetimes result from binding of both NADH to lactate dehydrogenase and NADPH to isocitrate dehydrogenase. The composite fluorescence anisotropy indicates the shorter (1.3-1.6 ns) decay component to be accompanied by local motion of the nicotinamide ring, pointing to attachment solely via the adenine moiety. For the longer lifetime (3.2-4.4 ns), the nicotinamide conformational freedom is found to be fully restricted. As full and partial nicotinamide binding are recognized steps in dehydrogenase catalysis, our results unify photophysical, structural, and functional aspects of NADH and NADPH binding and clarify the biochemical processes that underlie their contrasting intracellular lifetimes.
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Affiliation(s)
- Thomas S Blacker
- Department of Physics & Astronomy, University College London, London, United Kingdom; Research Department of Cell & Developmental Biology, University College London, London, United Kingdom
| | - Michael R Duchen
- Research Department of Cell & Developmental Biology, University College London, London, United Kingdom
| | - Angus J Bain
- Department of Physics & Astronomy, University College London, London, United Kingdom.
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3
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Blum D, Reuter M, Schliebs W, Tomaschewski J, Erdmann R, Wagner R. Membrane binding and pore forming insertion of PEX5 into horizontal lipid bilayer. Biol Chem 2023; 404:157-167. [PMID: 36260915 DOI: 10.1515/hsz-2022-0183] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2022] [Accepted: 08/29/2022] [Indexed: 11/15/2022]
Abstract
The assembly of the peroxisomal translocon involves the transition of a soluble form of the peroxisomal targeting receptor PEX5 into a membrane-bound form, which becomes an integral membrane component of the import pore for peroxisomal matrix proteins. How this transition occurs is still a mystery. We addressed this question using a artificial horizontal bilayer in combination with fluorescence time-correlated single photon counting (TCSPC) and electrophysiological channel recording. Purified human isoform PEX5L and truncated PEX5L(1-335) lacking the cargo binding domain were selectively labeled with thiol-reactive Atto-dyes. Diffusion coefficients of labeled protein in solution show that PEX5L is monomeric with a rather compact spherical conformation, while the truncated protein appeared in a more extended conformation. Labeled PEX5L and the truncated PEX5L(1-335) bind stably to horizontal bilayer thereby accumulating around 100-fold. The diffusion coefficients of the membrane-bound PEX5L forms are 3-4 times lower than in solution, indicating the formation of larger complexes. Electrophysiological single channel recording shows that membrane-bound labeled and non-labeled PEX5L, but not the truncated PEX5L(1-335), can form ion conducting membrane channels. The data suggest that PEX5L is the pore-forming component of the oligomeric peroxisomal translocon and that spontaneous PEX5L membrane surface binding might be an important step in its assembly.
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Affiliation(s)
- Daniel Blum
- MOLIFE Research Center, Jacobs, University Bremen, D-28759 Bremen, Germany
| | - Maren Reuter
- Institut für Biochemie und Pathobiochemie, Abt. Systembiochemie, Medizinische Fakultät, Ruhr-Universität Bochum, D-44801 Bochum, Germany
| | - Wolfgang Schliebs
- Institut für Biochemie und Pathobiochemie, Abt. Systembiochemie, Medizinische Fakultät, Ruhr-Universität Bochum, D-44801 Bochum, Germany
| | - Jana Tomaschewski
- Institut für Biochemie und Pathobiochemie, Abt. Systembiochemie, Medizinische Fakultät, Ruhr-Universität Bochum, D-44801 Bochum, Germany
| | - Ralf Erdmann
- Institut für Biochemie und Pathobiochemie, Abt. Systembiochemie, Medizinische Fakultät, Ruhr-Universität Bochum, D-44801 Bochum, Germany
| | - Richard Wagner
- MOLIFE Research Center, Jacobs, University Bremen, D-28759 Bremen, Germany
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4
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Yahav G, Weber Y, Duadi H, Pawar S, Fixler D. Classification of fluorescent anisotropy decay based on the distance approach in the frequency domain. OPTICS EXPRESS 2022; 30:6176-6192. [PMID: 35209559 DOI: 10.1364/oe.453108] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/05/2022] [Accepted: 02/01/2022] [Indexed: 06/14/2023]
Abstract
Frequency-domain (FD) fluorometry is a widely utilized tool to probe unique features of complex biological structures, which may serve medical diagnostic purposes. The conventional data analysis approaches used today to extract the fluorescence intensity or fluorescence anisotropy (FA) decay data suffer from several drawbacks and are inherently limited by the characteristics and complexity of the decay models. This paper presents the squared distance (D2) technique, which categorized samples based on the direct frequency response data (FRD) of the FA decay. As such, it improves the classification ability of the FD measurements of the FA decay as it avoids any distortion that results from the challenged translation into time domain data. This paper discusses the potential use of the D2 approach to classify biological systems. Mathematical formulation of D2 technique adjusted to the FRD of the FA decay is described. In addition, it validates the D2 approach using 2 simulated data sets of 6 groups with similar widely and closely spaced FA decay data as well as in experimental data of 4 samples of a fluorophore-solvent (fluorescein-glycerol) system. In the simulations, the classification accuracy was above 95% for all 6 groups. In the experimental data, the classification accuracy was 100%. The D2 approach can help classify samples whose FA decay data are difficult to extract making FA in the FD a realistic diagnostic tool. The D2 approach offers an advanced method for sorting biological samples with differences beyond the practical temporal resolution limit in a reliable and efficient manner based on the FRD of their time-resolved fluorescence measurements thereby achieving better diagnostic quality in a shorter time.
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5
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Bowman AJ, Kasevich MA. Resonant Electro-Optic Imaging for Microscopy at Nanosecond Resolution. ACS NANO 2021; 15:16043-16054. [PMID: 34546704 DOI: 10.1021/acsnano.1c04470] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
We demonstrate an electro-optic wide-field method to enable fluorescence lifetime microscopy (FLIM) with high throughput and single-molecule sensitivity. Resonantly driven Pockels cells are used to efficiently gate images at 39 MHz, allowing fluorescence lifetime to be captured on standard camera sensors. Lifetime imaging of single molecules is enabled in wide field with exposure times of less than 100 ms. This capability allows combination of wide-field FLIM with single-molecule super-resolution localization microscopy. Fast single-molecule dynamics such as FRET and molecular binding events are captured from wide-field images without prior spatial knowledge. A lifetime sensitivity of 1.9 times the photon shot-noise limit is achieved, and high throughput is shown by acquiring wide-field FLIM images with millisecond exposure and >108 photons per frame. Resonant electro-optic FLIM allows lifetime contrast in any wide-field microscopy method.
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Affiliation(s)
- Adam J Bowman
- Physics Department, Stanford University, 382 Via Pueblo Mall, Stanford, California 94305, United States
| | - Mark A Kasevich
- Physics Department, Stanford University, 382 Via Pueblo Mall, Stanford, California 94305, United States
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6
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Gebhardt C, Lehmann M, Reif MM, Zacharias M, Gemmecker G, Cordes T. Molecular and Spectroscopic Characterization of Green and Red Cyanine Fluorophores from the Alexa Fluor and AF Series*. Chemphyschem 2021; 22:1566-1583. [PMID: 34185946 PMCID: PMC8457111 DOI: 10.1002/cphc.202000935] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2020] [Revised: 06/01/2021] [Indexed: 12/23/2022]
Abstract
The use of fluorescence techniques has an enormous impact on various research fields including imaging, biochemical assays, DNA-sequencing and medical technologies. This has been facilitated by the development of numerous commercial dyes with optimized photophysical and chemical properties. Often, however, information about the chemical structures of dyes and the attached linkers used for bioconjugation remain a well-kept secret. This can lead to problems for research applications where knowledge of the dye structure is necessary to predict or understand (unwanted) dye-target interactions, or to establish structural models of the dye-target complex. Using a combination of optical spectroscopy, mass spectrometry, NMR spectroscopy and molecular dynamics simulations, we here investigate the molecular structures and spectroscopic properties of dyes from the Alexa Fluor (Alexa Fluor 555 and 647) and AF series (AF555, AF647, AFD647). Based on available data and published structures of the AF and Cy dyes, we propose a structure for Alexa Fluor 555 and refine that of AF555. We also resolve conflicting reports on the linker composition of Alexa Fluor 647 maleimide. We also conducted a comprehensive comparison between Alexa Fluor and AF dyes by continuous-wave absorption and emission spectroscopy, quantum yield determination, fluorescence lifetime and anisotropy spectroscopy of free and protein-attached dyes. All these data support the idea that Alexa Fluor and AF dyes have a cyanine core and are a derivative of Cy3 and Cy5. In addition, we compared Alexa Fluor 555 and Alexa Fluor 647 to their structural homologs AF555 and AF(D)647 in single-molecule FRET applications. Both pairs showed excellent performance in solution-based smFRET experiments using alternating laser excitation. Minor differences in apparent dye-protein interactions were investigated by molecular dynamics simulations. Our findings clearly demonstrate that the AF-fluorophores are an attractive alternative to Alexa- and Cy-dyes in smFRET studies or other fluorescence applications.
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Affiliation(s)
- Christian Gebhardt
- Physical and Synthetic Biology, Faculty of BiologyLudwig-Maximilians-Universität MünchenGroßhadernerstr. 2–482152Planegg-MartinsriedGermany
| | - Martin Lehmann
- Plant Molecular Biology, Faculty of BiologyLudwig-Maximilians-Universität MünchenGroßhadernerstr. 2–482152Planegg-MartinsriedGermany
| | - Maria M. Reif
- Theoretical Biophysics (T38), Physics DepartmentTechnical University of MunichCenter for Functional Protein Assemblies (CPA), Ernst-Otto-Fischer-Str. 885748GarchingGermany
| | - Martin Zacharias
- Theoretical Biophysics (T38), Physics DepartmentTechnical University of MunichCenter for Functional Protein Assemblies (CPA), Ernst-Otto-Fischer-Str. 885748GarchingGermany
| | - Gerd Gemmecker
- Bavarian NMR Center (B NMRZ), Department of ChemistryTechnical University of MunichLichtenbergstr. 485748GarchingGermany
| | - Thorben Cordes
- Physical and Synthetic Biology, Faculty of BiologyLudwig-Maximilians-Universität MünchenGroßhadernerstr. 2–482152Planegg-MartinsriedGermany
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7
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Lopes-de-Campos D, Pereira-Leite C, Fontaine P, Coutinho A, Prieto M, Sarmento B, Jakobtorweihen S, Nunes C, Reis S. Interface-Mediated Mechanism of Action-The Root of the Cytoprotective Effect of Immediate-Release Omeprazole. J Med Chem 2021; 64:5171-5184. [PMID: 33847502 DOI: 10.1021/acs.jmedchem.1c00251] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Omeprazole is usually administered under an enteric coating. However, there is a Food and Drug Administration-approved strategy that enables its release in the stomach. When locally absorbed, omeprazole shows a higher efficacy and a cytoprotective effect, whose mechanism was still unknown. Therefore, we aimed to assess the effect of the absorption route on the gastric mucosa. 2D and 3D models of dipalmitoylphosphatidylcholine (DPPC) at different pH values (5.0 and 7.4) were used to mimic different absorption conditions. Several experimental techniques, namely, fluorescence studies, X-ray scattering methodologies, and Langmuir monolayers coupled with microscopy, X-ray diffraction, and infrared spectroscopy techniques, were combined with molecular dynamics simulations. The results showed that electrostatic and hydrophobic interactions between omeprazole and DPPC rearranged the conformational state of DPPC. Omeprazole intercalates among DPPC molecules, promoting domain formation with untilted phospholipids. Hence, the local release of omeprazole enables its action as a phospholipid-like drug, which can reinforce and protect the gastric mucosa.
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Affiliation(s)
- Daniela Lopes-de-Campos
- LAQV, REQUIMTE, Departamento de Ciências Químicas, Faculdade de Farmácia, Universidade do Porto, 4050-313 Porto, Portugal
| | - Catarina Pereira-Leite
- LAQV, REQUIMTE, Departamento de Ciências Químicas, Faculdade de Farmácia, Universidade do Porto, 4050-313 Porto, Portugal
| | - Philippe Fontaine
- Synchrotron SOLEIL, L'Orme des Merisiers, Saint Aubin, BP48, 91192 Gif-sur-Yvette, France
| | - Ana Coutinho
- IBB-Institute for Bioengineering and Biosciences, Instituto Superior Técnico, Universidade de Lisboa, 1049-001 Lisboa, Portugal.,Departamento de Química e Bioquímica, Faculdade de Ciências, Universidade de Lisboa, 1749-016 Lisboa, Portugal
| | - Manuel Prieto
- IBB-Institute for Bioengineering and Biosciences, Instituto Superior Técnico, Universidade de Lisboa, 1049-001 Lisboa, Portugal
| | - Bruno Sarmento
- INEB-Instituto de Engenharia Biomédica, Universidade do Porto, 4200-135 Porto, Portugal.,i3S-Instituto de Investigação e Inovação em Saúde, Universidade do Porto, 4200-135 Porto, Portugal.,IINFACTS, Instituto de Investigação e Formação Avançada em Ciências e Tecnologias da Saúde, Instituto Universitário de Ciências da Saúde, 4585-116 Gandra, Portugal
| | - Sven Jakobtorweihen
- Institute of Thermal Separation Processes, Hamburg University of Technology, 21073 Hamburg, Germany
| | - Cláudia Nunes
- LAQV, REQUIMTE, Departamento de Ciências Químicas, Faculdade de Farmácia, Universidade do Porto, 4050-313 Porto, Portugal
| | - Salette Reis
- LAQV, REQUIMTE, Departamento de Ciências Químicas, Faculdade de Farmácia, Universidade do Porto, 4050-313 Porto, Portugal
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8
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Panigrahi SK, Mishra AK. Total Emission Time Resolved Decay: a Method for Measurement and Resolution of Broad-Band Emission. J Fluoresc 2020; 30:1085-1094. [PMID: 32632718 DOI: 10.1007/s10895-020-02581-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2020] [Accepted: 06/26/2020] [Indexed: 10/23/2022]
Abstract
This article reports a time-resolved fluorescence data acquisition technique termed as "Total Emission Time Resolved Decay" (TETRD). TETRD is recorded by using zero-order diffraction of emission grating in TCSPC instrument. TETRD decay curve has entire wavelength dependent decay information buried in it. Cut-off filters are used to avoid scattering contamination. Two existing approaches are used for analysing the interconnected TETRD data. (i) First, global analysis: for discretely decaying multiple components, TETRD dataset is analyzed using global analysis. The normalized pre-exponentials (αi) and relative amplitudes (fi) recovered from global analysis reflect the individual component emission more faithfully and resembles with steady-state spectral data as well. (ii) Second, stretched exponential fitting (StrEF): for continuous lifetime distribution systems, StrEF (I(t) = I0 exp[-(t/τ)1/h]) has been used to analyse TETRD data. The average lifetime (τ) of StrEF matches well with the average lifetime of multi-exponential fitting, the heterogeneity factor (h) of StrEF is an additional parameter, which informs about local heterogeneity in the system. It is shown that the lifetimes obtained with TETRD matches well with the lifetimes obtained using conventional time resolved emission spectra (TRES). TETRD holds advantage in rapid data acquisition and facilitates inclusion of another variable (like concentration, solvent composition, pH, excitation wavelength etc.) into experimental design. Further, with the use of an appropriate data analysis tool, the multi-component decay profiles can be resolved conveniently.
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9
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Ray S, Singh N, Kumar R, Patel K, Pandey S, Datta D, Mahato J, Panigrahi R, Navalkar A, Mehra S, Gadhe L, Chatterjee D, Sawner AS, Maiti S, Bhatia S, Gerez JA, Chowdhury A, Kumar A, Padinhateeri R, Riek R, Krishnamoorthy G, Maji SK. α-Synuclein aggregation nucleates through liquid-liquid phase separation. Nat Chem 2020; 12:705-716. [PMID: 32514159 DOI: 10.1038/s41557-020-0465-9] [Citation(s) in RCA: 369] [Impact Index Per Article: 92.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2019] [Accepted: 04/07/2020] [Indexed: 12/22/2022]
Abstract
α-Synuclein (α-Syn) aggregation and amyloid formation is directly linked with Parkinson's disease pathogenesis. However, the early events involved in this process remain unclear. Here, using the in vitro reconstitution and cellular model, we show that liquid-liquid phase separation of α-Syn precedes its aggregation. In particular, in vitro generated α-Syn liquid-like droplets eventually undergo a liquid-to-solid transition and form an amyloid hydrogel that contains oligomers and fibrillar species. Factors known to aggravate α-Syn aggregation, such as low pH, phosphomimetic substitution and familial Parkinson's disease mutations, also promote α-Syn liquid-liquid phase separation and its subsequent maturation. We further demonstrate α-Syn liquid-droplet formation in cells. These cellular α-Syn droplets eventually transform into perinuclear aggresomes, the process regulated by microtubules. This work provides detailed insights into the phase-separation behaviour of natively unstructured α-Syn and its conversion to a disease-associated aggregated state, which is highly relevant in Parkinson's disease pathogenesis.
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Affiliation(s)
- Soumik Ray
- Department of Biosciences and Bioengineering, IIT Bombay, Mumbai, India
| | - Nitu Singh
- Department of Biosciences and Bioengineering, IIT Bombay, Mumbai, India
| | - Rakesh Kumar
- Department of Biosciences and Bioengineering, IIT Bombay, Mumbai, India
| | - Komal Patel
- Department of Biosciences and Bioengineering, IIT Bombay, Mumbai, India
| | | | - Debalina Datta
- Department of Biosciences and Bioengineering, IIT Bombay, Mumbai, India
| | | | | | - Ambuja Navalkar
- Department of Biosciences and Bioengineering, IIT Bombay, Mumbai, India
| | - Surabhi Mehra
- Department of Biosciences and Bioengineering, IIT Bombay, Mumbai, India
| | - Laxmikant Gadhe
- Department of Biosciences and Bioengineering, IIT Bombay, Mumbai, India
| | | | - Ajay Singh Sawner
- Department of Biosciences and Bioengineering, IIT Bombay, Mumbai, India
| | - Siddhartha Maiti
- Department of Biosciences and Bioengineering, IIT Bombay, Mumbai, India
| | - Sandhya Bhatia
- National Center for Biological Sciences, Tata Institute of Fundamental Research, Bengaluru, India
| | - Juan Atilio Gerez
- Department of Chemistry and Applied Biosciences, ETH Zurich, Zürich, Switzerland
| | | | - Ashutosh Kumar
- Department of Biosciences and Bioengineering, IIT Bombay, Mumbai, India
| | | | - Roland Riek
- Department of Chemistry and Applied Biosciences, ETH Zurich, Zürich, Switzerland
| | | | - Samir K Maji
- Department of Biosciences and Bioengineering, IIT Bombay, Mumbai, India.
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10
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Steinmark IE, Chung PH, Ziolek RM, Cornell B, Smith P, Levitt JA, Tregidgo C, Molteni C, Yahioglu G, Lorenz CD, Suhling K. Time-Resolved Fluorescence Anisotropy of a Molecular Rotor Resolves Microscopic Viscosity Parameters in Complex Environments. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2020; 16:e1907139. [PMID: 32363742 DOI: 10.1002/smll.201907139] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/06/2019] [Revised: 02/14/2020] [Accepted: 03/06/2020] [Indexed: 06/11/2023]
Abstract
Understanding viscosity in complex environments remains a largely unanswered question despite its importance in determining reaction rates in vivo. Here, time-resolved fluorescence anisotropy imaging (TR-FAIM) is combined with fluorescent molecular rotors (FMRs) to simultaneously determine two non-equivalent viscosity-related parameters in complex heterogeneous environments. The parameters, FMR rotational correlation time and lifetime, are extracted from fluorescence anisotropy decays, which in heterogeneous environments show dip-and-rise behavior due to multiple dye populations. Decays of this kind are found both in artificially constructed adiposomes and in live cell lipid droplet organelles. Molecular dynamics simulations are used to assign each population to nano-environments within the lipid systems. The less viscous population corresponds to the state showing an average 25° tilt to the lipid membrane normal, and the more viscous population to the state showing an average 55° tilt. This combined experimental and simulation approach enables a comprehensive description of the FMR probe behavior within viscous nano-environments in complex, biological systems.
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Affiliation(s)
| | | | | | | | - Paul Smith
- Department of Physics, King's College London, UK
| | - James A Levitt
- Randall Centre for Cell & Molecular Biophysics, King's College London, UK
| | - Carolyn Tregidgo
- Department of Physics, King's College London, UK
- Genomics England, London, EC1M 6BQ, UK
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11
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El-Taboni F, Caseley E, Katsikogianni M, Swanson L, Swift T, Romero-González ME. Fluorescence Spectroscopy Analysis of the Bacteria-Mineral Interface: Adsorption of Lipopolysaccharides to Silica and Alumina. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2020; 36:1623-1632. [PMID: 31957449 PMCID: PMC7145363 DOI: 10.1021/acs.langmuir.9b02158] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
We present here a quantification of the sorption process and molecular conformation involved in the attachment of bacterial cell wall lipopolysaccharides (LPSs), extracted from Escherichia coli, to silica (SiO2) and alumina (Al2O3) particles. We propose that interfacial forces govern the physicochemical interactions of the bacterial cell wall with minerals in the natural environment, and the molecular conformation of LPS cell wall components depends on both the local charge at the point of binding and hydrogen bonding potential. This has an effect on bacterial adaptation to the host environment through adhesion, growth, function, and ability to form biofilms. Photophysical techniques were used to investigate adsorption of fluorescently labeled LPS onto mineral surfaces as model systems for bacterial attachment. Adsorption of macromolecules in dilute solutions was studied as a function of pH and ionic strength in the presence of alumina and silica via fluorescence, potentiometric, and mass spectrometry techniques. The effect of silica and alumina particles on bacterial growth as a function of pH was also investigated using spectrophotometry. The alumina and silica particles were used to mimic active sites on the surface of clay and soil particles, which serve as a point of attachment of bacteria in natural systems. It was found that LPS had a high adsorption affinity for Al2O3 while adsorbing weakly to SiO2 surfaces. Strong adsorption was observed at low pH for both minerals and varied with both pH and mineral concentration, likely in part due to conformational rearrangement of the LPS macromolecules. Bacterial growth was also enhanced in the presence of the particles at low pH values. This demonstrates that at a molecular level, bacterial cell wall components are able to adapt their conformation, depending on the solution pH, in order to maximize attachment to substrates and guarantee community survival.
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Affiliation(s)
- Fateh El-Taboni
- Department
of Chemistry, University of Benghazi, Benghazi Qar Yunis 9480, Libya
| | - Emily Caseley
- School
of Chemistry and Biosciences, University
of Bradford, Bradford BD7 1DP, U.K.
| | - Maria Katsikogianni
- School
of Chemistry and Biosciences, University
of Bradford, Bradford BD7 1DP, U.K.
| | - Linda Swanson
- Department
of Chemistry, The University of Sheffield, Sheffield S10 2TN, U.K.
| | - Thomas Swift
- School
of Chemistry and Biosciences, University
of Bradford, Bradford BD7 1DP, U.K.
- E-mail: (T.S.)
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12
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Silori Y, De AK. Controlling balance between homo-FRET and hetero-FRET within hetero-chromophoric systems by tuning nature of solvent. J Mol Liq 2020. [DOI: 10.1016/j.molliq.2019.112093] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
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13
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Buck JT, Wilson RW, Mani T. Intramolecular Long-Range Charge-Transfer Emission in Donor-Bridge-Acceptor Systems. J Phys Chem Lett 2019; 10:3080-3086. [PMID: 31117690 DOI: 10.1021/acs.jpclett.9b01269] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Charge recombination to the electronic ground state typically occurs nonradiatively. We report a rational design of donor-bridge-acceptor molecules that exhibit charge-transfer (CT) emission through conjugated bridges over distances of up to 24 Å. The emission is enhanced by intensity borrowing and extends into the near-IR region. Efficient charge recombination to the initial excited state results in recombination fluorescence. We have established the identity of CT emission by solvent dependence, sensitivity to temperature, femtosecond transient absorption spectroscopy, and unique emission polarization patterns. Large excited-state electronic couplings and small energy gaps enable the observation of intramolecular long-range CT emission over the unprecedented long distance. These results open new possibilities of using intramolecular long-range CT emission in molecular electronic and biomedical imaging probe applications.
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Affiliation(s)
- Jason T Buck
- Department of Chemistry , University of Connecticut , Storrs , Connecticut 06269-3060 , United States
| | - Reid W Wilson
- Department of Chemistry , University of Connecticut , Storrs , Connecticut 06269-3060 , United States
| | - Tomoyasu Mani
- Department of Chemistry , University of Connecticut , Storrs , Connecticut 06269-3060 , United States
- JST, PRESTO , 4-1-8 Honcho , Kawaguchi , Saitama 332-0012 , Japan
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Camacho R, Täuber D, Scheblykin IG. Fluorescence Anisotropy Reloaded-Emerging Polarization Microscopy Methods for Assessing Chromophores' Organization and Excitation Energy Transfer in Single Molecules, Particles, Films, and Beyond. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2019; 31:e1805671. [PMID: 30721532 DOI: 10.1002/adma.201805671] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/31/2018] [Revised: 11/12/2018] [Indexed: 06/09/2023]
Abstract
Fluorescence polarization is widely used to assess the orientation/rotation of molecules, and the excitation energy transfer between closely located chromophores. Emerging since the 1990s, single molecule fluorescence spectroscopy and imaging stimulate the application of light polarization for studying molecular organization and energy transfer beyond ensemble averaging. Here, traditional fluorescence polarization and linear dichroism methods used for bulk samples are compared with techniques specially developed for, or inspired by, single molecule fluorescence spectroscopy. Techniques for assessing energy transfer in anisotropic samples, where the traditional fluorescence anisotropy framework is not readily applicable, are discussed in depth. It is shown that the concept of a polarization portrait and the single funnel approximation can lay the foundation for alternative energy transfer metrics. Examples ranging from fundamental studies of photoactive materials (conjugated polymers, light-harvesting aggregates, and perovskite semiconductors) to Förster resonant energy transfer (FRET)-based biomedical imaging are presented. Furthermore, novel uses of light polarization for super-resolution optical imaging are mentioned as well as strategies for avoiding artifacts in polarization microscopy.
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Affiliation(s)
- Rafael Camacho
- Department of Chemistry, KU Leuven, Celestijnenlaan 200F, B-3001, Leuven, Belgium
| | - Daniela Täuber
- Chemical Physics and NanoLund, Lund University, P.O. Box 124, SE-22100, Lund, Sweden
- Biopolarisation, Leibniz Institute of Photonic Technology, Albert-Einstein-Str. 9, D-07745, Jena, Germany
- Institute of Solid State Physics, FSU Jena, Helmholtzweg 3, D-07743, Jena, Germany
| | - Ivan G Scheblykin
- Chemical Physics and NanoLund, Lund University, P.O. Box 124, SE-22100, Lund, Sweden
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16
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Behboudi H, Mehdipour G, Safari N, Pourmadadi M, Saei A, Omidi M, Tayebi L, Rahmandoust M. Carbon Quantum Dots in Nanobiotechnology. ADVANCED STRUCTURED MATERIALS 2019. [DOI: 10.1007/978-3-030-10834-2_6] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
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17
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Möckel C, Kubiak J, Schillinger O, Kühnemuth R, Della Corte D, Schröder GF, Willbold D, Strodel B, Seidel CAM, Neudecker P. Integrated NMR, Fluorescence, and Molecular Dynamics Benchmark Study of Protein Mechanics and Hydrodynamics. J Phys Chem B 2018; 123:1453-1480. [DOI: 10.1021/acs.jpcb.8b08903] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Affiliation(s)
- Christina Möckel
- Institut für Physikalische Biologie, Heinrich-Heine-Universität Düsseldorf, 40225 Düsseldorf, Germany
- Institute of Complex Systems (ICS-6: Structural Biochemistry), Forschungszentrum Jülich, 52425 Jülich, Germany
| | - Jakub Kubiak
- Lehrstuhl für Molekulare Physikalische Chemie, Heinrich-Heine-Universität Düsseldorf, 40225 Düsseldorf, Germany
| | - Oliver Schillinger
- Institute of Complex Systems (ICS-6: Structural Biochemistry), Forschungszentrum Jülich, 52425 Jülich, Germany
- Institut für Theoretische Chemie und Computerchemie, Heinrich-Heine-Universität Düsseldorf, 40225 Düsseldorf, Germany
| | - Ralf Kühnemuth
- Lehrstuhl für Molekulare Physikalische Chemie, Heinrich-Heine-Universität Düsseldorf, 40225 Düsseldorf, Germany
| | - Dennis Della Corte
- Institute of Complex Systems (ICS-6: Structural Biochemistry), Forschungszentrum Jülich, 52425 Jülich, Germany
| | - Gunnar F. Schröder
- Institute of Complex Systems (ICS-6: Structural Biochemistry), Forschungszentrum Jülich, 52425 Jülich, Germany
- Physics Department, Heinrich-Heine-Universität Düsseldorf, 40225 Düsseldorf, Germany
| | - Dieter Willbold
- Institut für Physikalische Biologie, Heinrich-Heine-Universität Düsseldorf, 40225 Düsseldorf, Germany
- Institute of Complex Systems (ICS-6: Structural Biochemistry), Forschungszentrum Jülich, 52425 Jülich, Germany
| | - Birgit Strodel
- Institute of Complex Systems (ICS-6: Structural Biochemistry), Forschungszentrum Jülich, 52425 Jülich, Germany
- Institut für Theoretische Chemie und Computerchemie, Heinrich-Heine-Universität Düsseldorf, 40225 Düsseldorf, Germany
| | - Claus A. M. Seidel
- Lehrstuhl für Molekulare Physikalische Chemie, Heinrich-Heine-Universität Düsseldorf, 40225 Düsseldorf, Germany
| | - Philipp Neudecker
- Institut für Physikalische Biologie, Heinrich-Heine-Universität Düsseldorf, 40225 Düsseldorf, Germany
- Institute of Complex Systems (ICS-6: Structural Biochemistry), Forschungszentrum Jülich, 52425 Jülich, Germany
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18
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Observation of the linewidth broadening of single spins in diamond nanoparticles in aqueous fluid and its relation to the rotational Brownian motion. Sci Rep 2018; 8:14773. [PMID: 30283007 PMCID: PMC6170451 DOI: 10.1038/s41598-018-33041-6] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2018] [Accepted: 09/18/2018] [Indexed: 11/08/2022] Open
Abstract
Capturing the fast rotational motion of single nanoparticles has been hindered owing to the difficulty of acquiring directional information under the optical diffraction limit. Here, we report the linewidth broadening of the electron spin resonance of single nitrogen vacancy (NV) centers that matches the rotational diffusion constant of the host nanodiamonds. When nanodiamonds are gradually detached from the substrates that they were fixed to, their optically detected spin resonance peaks are broadened by 1.8 MHz, which corresponds to the rotational diffusion constant of nanoparticles with a diameter of 11.4 nm from the Einstein–Smoluchowski relation.
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19
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Sethy R, Métivier R, Brosseau A, Kawai T, Nakashima T. Impact of Optical Purity on the Light Harvesting Property in Supramolecular Nanofibers. J Phys Chem Lett 2018; 9:4516-4521. [PMID: 30048139 DOI: 10.1021/acs.jpclett.8b02015] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Supramolecular ordering and orientation of chromophores are tremendously accomplished in photosynthetic light harvesting complexes, which are crucial for long-range transfer of collected solar energy. We herein demonstrate the importance of optical purity on the organization of chromophoric chiral molecules for efficient energy migration. Enantiomeric bichromophoric compounds, which self-assemble into nanofibers capable of chiral recognition, were mixed to form supramolecular coassemblies with variable enantiopurity. The chiral molecules self-assembled into extended fibers regardless of enantiopurity, while their morphology was dependent on the enantiomeric excess. The optical purity of assemblies also had an effect on the emission efficiency; the nanofibers with higher enantiomeric excess afforded a larger emission quantum yield. The presence of an opposite enantiomer is considered to deteriorate the chiral molecular packing suitable for directional growth of the nanofiber, efficient exciton migration, and chiral guest recognition.
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Affiliation(s)
- Ramarani Sethy
- Graduate School of Science and Technology, Division of Materials Science , Nara Institute of Science and Technology (NAIST) , Ikoma , Nara 630-0192 , Japan
| | - Rémi Métivier
- PPSM, ENS Cachan, CNRS , Université Paris-Saclay , 94235 Cachan , France
| | - Arnaud Brosseau
- PPSM, ENS Cachan, CNRS , Université Paris-Saclay , 94235 Cachan , France
| | - Tsuyoshi Kawai
- Graduate School of Science and Technology, Division of Materials Science , Nara Institute of Science and Technology (NAIST) , Ikoma , Nara 630-0192 , Japan
| | - Takuya Nakashima
- Graduate School of Science and Technology, Division of Materials Science , Nara Institute of Science and Technology (NAIST) , Ikoma , Nara 630-0192 , Japan
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20
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Pautov V, Nekrasova T. Nanosecond dynamics of polymers with complex architecture as studied by polarized luminescence. POLYMER 2018. [DOI: 10.1016/j.polymer.2018.03.051] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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21
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Affiliation(s)
- David J S Birch
- Photophysics Group, Department of Physics, University of Strathclyde, Scottish Universities Physics Alliance, Glasgow G4 0NG, Scotland, United Kingdom
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22
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Mancini O, Wellbrock T, Rolinski OJ, Kubiak-Ossowska K, Mulheran PA. Probing beta amyloid aggregation using fluorescence anisotropy: experiments and simulation. Phys Chem Chem Phys 2018; 20:4216-4225. [DOI: 10.1039/c7cp08217g] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
Simulated fluorescence anisotropy from Tyr residues distinguishes a beta amyloid monomer (black) from oligomers (coloured).
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Affiliation(s)
- Onorio Mancini
- Department of Chemical Engineering and Process Engineering
- University of Strathclyde
- Glasgow
- UK
| | | | | | | | - Paul A. Mulheran
- Department of Chemical Engineering and Process Engineering
- University of Strathclyde
- Glasgow
- UK
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23
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Novikov EG, Skakun VV, Borst JW, Visser AJWG. Maximum entropy analysis of polarized fluorescence decay of (E)GFP in aqueous solution. Methods Appl Fluoresc 2017; 6:014001. [PMID: 28858857 DOI: 10.1088/2050-6120/aa898b] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
The maximum entropy method (MEM) was used for the analysis of polarized fluorescence decays of enhanced green fluorescent protein (EGFP) in buffered water/glycerol mixtures, obtained with time-correlated single-photon counting (Visser et al 2016 Methods Appl. Fluoresc. 4 035002). To this end, we used a general-purpose software module of MEM that was earlier developed to analyze (complex) laser photolysis kinetics of ligand rebinding reactions in oxygen binding proteins. We demonstrate that the MEM software provides reliable results and is easy to use for the analysis of both total fluorescence decay and fluorescence anisotropy decay of aqueous solutions of EGFP. The rotational correlation times of EGFP in water/glycerol mixtures, obtained by MEM as maxima of the correlation-time distributions, are identical to the single correlation times determined by global analysis of parallel and perpendicular polarized decay components. The MEM software is also able to determine homo-FRET in another dimeric GFP, for which the transfer correlation time is an order of magnitude shorter than the rotational correlation time. One important advantage utilizing MEM analysis is that no initial guesses of parameters are required, since MEM is able to select the least correlated solution from the feasible set of solutions.
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Affiliation(s)
- Eugene G Novikov
- Institut Curie-Recherche (INSERM U350), Centre Universitaire, F-91405 Orsay, France. Carl Zeiss Microscopy GmbH, D-07745 Jena, Germany
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24
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Fernandes DD, Bamrah J, Kailasam S, Gomes GNW, Li Y, Wieden HJ, Gradinaru CC. Characterization of Fluorescein Arsenical Hairpin (FlAsH) as a Probe for Single-Molecule Fluorescence Spectroscopy. Sci Rep 2017; 7:13063. [PMID: 29026195 PMCID: PMC5638890 DOI: 10.1038/s41598-017-13427-8] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2017] [Accepted: 09/21/2017] [Indexed: 01/27/2023] Open
Abstract
In recent years, new labelling strategies have been developed that involve the genetic insertion of small amino-acid sequences for specific attachment of small organic fluorophores. Here, we focus on the tetracysteine FCM motif (FLNCCPGCCMEP), which binds to fluorescein arsenical hairpin (FlAsH), and the ybbR motif (TVLDSLEFIASKLA) which binds fluorophores conjugated to Coenzyme A (CoA) via a phosphoryl transfer reaction. We designed a peptide containing both motifs for orthogonal labelling with FlAsH and Alexa647 (AF647). Molecular dynamics simulations showed that both motifs remain solvent-accessible for labelling reactions. Fluorescence spectra, correlation spectroscopy and anisotropy decay were used to characterize labelling and to obtain photophysical parameters of free and peptide-bound FlAsH. The data demonstrates that FlAsH is a viable probe for single-molecule studies. Single-molecule imaging confirmed dual labeling of the peptide with FlAsH and AF647. Multiparameter single-molecule Förster Resonance Energy Transfer (smFRET) measurements were performed on freely diffusing peptides in solution. The smFRET histogram showed different peaks corresponding to different backbone and dye orientations, in agreement with the molecular dynamics simulations. The tandem of fluorophores and the labelling strategy described here are a promising alternative to bulky fusion fluorescent proteins for smFRET and single-molecule tracking studies of membrane proteins.
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Affiliation(s)
- Dennis D Fernandes
- Department of Physics, University of Toronto, Toronto, Ontario, M5S 1A7, Canada.
- Department of Chemical & Physical Sciences, University of Toronto Mississauga, Mississauga, Ontario, L5L 1C6, Canada.
| | - Jasbir Bamrah
- Department of Chemical & Physical Sciences, University of Toronto Mississauga, Mississauga, Ontario, L5L 1C6, Canada
| | - Senthilkumar Kailasam
- Alberta RNA Research & Training Institute, Department of Chemistry & Biochemistry, University of Lethbridge, Lethbridge, Alberta, T1K 3M4, Canada
| | - Gregory-Neal W Gomes
- Department of Physics, University of Toronto, Toronto, Ontario, M5S 1A7, Canada
- Department of Chemical & Physical Sciences, University of Toronto Mississauga, Mississauga, Ontario, L5L 1C6, Canada
| | - Yuchong Li
- Department of Physics, University of Toronto, Toronto, Ontario, M5S 1A7, Canada
- Department of Chemical & Physical Sciences, University of Toronto Mississauga, Mississauga, Ontario, L5L 1C6, Canada
| | - Hans-Joachim Wieden
- Alberta RNA Research & Training Institute, Department of Chemistry & Biochemistry, University of Lethbridge, Lethbridge, Alberta, T1K 3M4, Canada
| | - Claudiu C Gradinaru
- Department of Physics, University of Toronto, Toronto, Ontario, M5S 1A7, Canada.
- Department of Chemical & Physical Sciences, University of Toronto Mississauga, Mississauga, Ontario, L5L 1C6, Canada.
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25
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Rapson AC, Gee ML, Clayton AHA, Smith TA. Interactions of a lytic peptide with supported lipid bilayers investigated by time-resolved evanescent wave-induced fluorescence spectroscopy. Methods Appl Fluoresc 2016; 4:044001. [DOI: 10.1088/2050-6120/4/4/044001] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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26
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Xu WL, Zeng P, Wu B, Zheng F, Zhu F, Smith TA, Ghiggino KP, Hao XT. Effects of Processing Solvent on the Photophysics and Nanomorphology of Poly(3-butyl-thiophene) Nanowires:PCBM Blends. J Phys Chem Lett 2016; 7:1872-1879. [PMID: 27140304 DOI: 10.1021/acs.jpclett.6b00808] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
We report the effect of the processing solvent on the nanoscale morphology and photophysical dynamics of poly(3-butyl-thiophene) nanowires (P3BT-nw). P3BT-nw assembled in ortho-dichlorobenzene (ODCB) show higher crystallization and a longer conjugation length with increased exciton delocalization compared with those assembled in chlorobenzene (CB). It is proposed that this solvent effect is associated with the higher ordered structures formed from ODCB solution state. Charge-transfer dynamics and phase separation for P3BT-nw:PCBM blends were investigated by ultrafast fluorescence techniques. The more efficient fluorescence quenching observed in P3BT-nw:PCBM blend films processed from ODCB suggests that there is intimate contact between P3BT-nw and PCBM that facilitates charge transfer. The superior performance of organic photovoltaic devices based on P3BT-nw:PCBM bulk heterojunctions processed using ODCB is attributed to the higher crystallization of P3BT-nw, optimized phase separation, and more efficient charge transfer from P3BT-nw to PCBM.
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Affiliation(s)
- Wei-Long Xu
- School of Physics, State Key Laboratory of Crystal Materials, Shandong University , Jinan, Shandong 250100, China
| | - Peng Zeng
- School of Chemistry, The University of Melbourne , Parkville, Victoria 3010, Australia
| | - Bo Wu
- Department of Physics, Institute of Advanced Materials and Institute of Research and Continuing Education (Shenzhen), Hong Kong Baptist University , Hong Kong
| | - Fei Zheng
- School of Physics, State Key Laboratory of Crystal Materials, Shandong University , Jinan, Shandong 250100, China
| | - Furong Zhu
- Department of Physics, Institute of Advanced Materials and Institute of Research and Continuing Education (Shenzhen), Hong Kong Baptist University , Hong Kong
| | - Trevor A Smith
- School of Chemistry, The University of Melbourne , Parkville, Victoria 3010, Australia
| | - Kenneth P Ghiggino
- School of Chemistry, The University of Melbourne , Parkville, Victoria 3010, Australia
| | - Xiao-Tao Hao
- School of Physics, State Key Laboratory of Crystal Materials, Shandong University , Jinan, Shandong 250100, China
- School of Chemistry, The University of Melbourne , Parkville, Victoria 3010, Australia
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27
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Birch D, Mely Y, Wolfbeis O. A journal in ascendancy. Methods Appl Fluoresc 2015; 3:040203. [PMID: 29148502 DOI: 10.1088/2050-6120/3/4/040203] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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28
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Kyrychenko A. Using fluorescence for studies of biological membranes: a review. Methods Appl Fluoresc 2015; 3:042003. [DOI: 10.1088/2050-6120/3/4/042003] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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