Article
Chemistry, Physical
Weiqing Yang, Zhihong Wei, Yan Nie, Yuxi Tian
Summary: Since its first optical detection in 1989, single-molecule spectroscopy has rapidly developed and been widely applied. However, the low photon emission efficiency of majority of matter limits the applications of photoluminescence-based optical methods. Efforts have been made to directly image nonfluorescent matter using different methods based on light-matter absorption or scattering. In this review, we discuss five popular methods, including dark-field microscopy (DFM), surface plasmon resonance microscopy (SPRM), surface enhanced Raman microscopy (SERM), interferometric scattering microscopy (iSCAT), and photothermal microscopy (PTM), for imaging nonfluorescent particles/molecules. We summarize the principles, applications, advantages, and disadvantages of each method and discuss further development and applications.
JOURNAL OF PHYSICAL CHEMISTRY LETTERS
(2022)
Article
Physics, Applied
Milan Vala, David Palounek, Hadrien M. L. Robert, Marek Piliarik
Summary: This study quantifies the scattering anisotropy of single unlabeled microtubules with high precision using polarization-sensitive microscopy. The research explains the structural origin of microtubule anisotropy and monitors the impact of tau protein binding on microtubules.
JOURNAL OF PHYSICS D-APPLIED PHYSICS
(2021)
Article
Chemistry, Analytical
Di Jiang, Xiaona Zhao, Yi-Nan Liu, Hai-Bo Chen, Wen-Li Lv, Chen Qian, Xian-Wei Liu
Summary: The study introduces a label-free optical imaging technology that can detect molecule binding kinetics by tracking charge-sensitive variations in the oscillation amplitude with sub-nanometer precision, allowing for the measurement of small molecules and metal ions binding to the surface as well as protein-protein binding kinetics. This capability offers a promising platform for screening small-molecule drugs, probing conformational changes in proteins, and detecting environmental pollutants.
ANALYTICAL CHEMISTRY
(2021)
Article
Physics, Applied
Ching-Ya Cheng, Yi-Hung Liao, Chia-Lung Hsieh
Summary: iSCAT microscopy is a powerful tool for single nanoparticle tracking with high resolution, utilizing metallic nanoparticles to distinguish signals from backgrounds. Reduction of localization errors and minimizing cell background influence are essential for accurate interpretation of single-particle diffusion data.
JOURNAL OF PHYSICS D-APPLIED PHYSICS
(2021)
Article
Multidisciplinary Sciences
Tobias F. Bartsch, Camila M. Villasante, Felicitas E. Hengel, Ahmed Toure, Daniel M. Firester, Aaron Oswald, A. J. Hudspeth
Summary: In high-speed single-molecule experiments, tethering proteins with force probes can avoid nonspecific interactions, but dissipate rapidly exerted forces through long linkers; due to the high frequency of mammalian hearing, short tethers are required for single-molecule experiments.
SCIENTIFIC REPORTS
(2021)
Article
Chemistry, Analytical
Xinyu Zhou, Rui Wang, Zijian Wan, Pengfei Zhang, Shaopeng Wang
Summary: In this study, we demonstrate multiplexed protein detection and parallel protein interaction analysis through evanescent scattering microscopy (ESM). ESM allows label-free digital single-molecule counting for binding kinetics measurement, improving counting efficiency and accuracy. We show that digital single-molecule counting can differentiate proteins with different molecular weights, enabling real-time monitoring of protein binding processes in solution. Additionally, we show that this strategy can analyze the kinetics of two different protein interaction processes simultaneously, both on surfaces and in solution. This work may provide a way to investigate complex protein interactions, such as the competition between biomarker-antibody binding in biofluids and biomarker-protein binding on cellular membranes.
ANALYTICAL CHEMISTRY
(2023)
Article
Biochemical Research Methods
M. Hannah Choi, Liu Hong, Leonardo P. Chamorro, Boyd Edwards, Aaron T. Timperman
Summary: The ability to measure the charge and size of single particles is crucial for understanding particle adhesion and interaction with the environment. The new technique called TrACE combines particle tracking velocimetry (PTV) and AC electrophoresis to accurately measure the charge and size of particles. This technique shows promise in studying the physical properties of cells and has potential applications in various fields.
Article
Biochemistry & Molecular Biology
Bei Liu, Orrin J. Stone, Michael Pablo, J. Cody Herron, Ana T. Nogueira, Onur Dagliyan, Jonathan B. Grimm, Luke D. Lavis, Timothy C. Elston, Klaus M. Hahn
Summary: The approach utilizes binder/tag to study the conformation of individual proteins during single particle tracking in living cells, allowing for the tracking of protein trajectory and conformation, and providing highly specific biosensors.
Article
Chemistry, Analytical
Xinyu Zhou, Rui Wang, Zijian Wan, Pengfei Zhang, Shaopeng Wang
Summary: Multiplexed protein detection and parallel protein interaction analysis are achieved using evanescent scattering microscopy (ESM), enabling label-free digital single-molecule counting with high temporal resolution. This strategy allows for real-time tracking of protein binding processes and simultaneous analysis of multiple protein interactions.
ANALYTICAL CHEMISTRY
(2023)
Article
Biology
Thomas G. W. Graham, John Joseph Ferrie, Gina M. Dailey, Robert Tjian, Xavier Darzacq
Summary: Single-molecule imaging is a powerful tool for studying biochemical processes in live cells, but tracking single molecules and detecting their interactions simultaneously remains challenging. This study describes a novel property of rhodamine dyes, proximity-assisted photoactivation (PAPA), which allows the detection of protein-protein interactions in live cells using two different labeled protein complexes in proximity.
Article
Biology
Nadia M. Huisjes, Thomas M. Retzer, Matthias J. Scherr, Rohit Agarwal, Lional Rajappa, Barbara Safaric, Anita Minnen, Karl E. Duderstadt
Summary: The rapid development of new imaging approaches has led to the generation of larger and more complex datasets, allowing us to uncover the time evolution of individual cells and biomolecules. However, there are currently few standards for processing these information-rich datasets, which poses challenges for wider dissemination. In this study, we introduce Mars, an open-source platform that stores and processes image-derived properties of biomolecules. Mars provides a flexible solution for reproducible analysis of image-derived properties and facilitates the discovery and quantitative classification of new biological phenomena.
Article
Biochemistry & Molecular Biology
Boris I. Godoy, Nicholas A. Vickers, Sean B. Andersson
Summary: Single Particle Tracking (SPT) is a powerful method for studying biomolecular dynamics in living cells, revealing trajectories of individual particles and motion model parameters. However, existing algorithms assume constant parameters, while this study proposes an estimation algorithm to determine time-varying parameters in systems that switch between different linear models of motion.
Review
Chemistry, Analytical
Lin Wei, Zhongju Ye, Chen Zhang, Hua Liu, Jie Yuan, Lehui Xiao
Summary: The goal of developing sensing methods for biomolecular assay is to provide new tools for discerning trace molecules in complex biological environments with high sensitivity and specificity. Single-molecule detection allows for resolution of small differences between ostensibly identical samples that cannot be achieved with ensemble measurements. Efforts have been made on exploiting single-molecule detection methods for early disease diagnosis. In this review, recent achievements in single-molecule detection with optical microscopy are summarized, including statistical single-molecule counting with total internal reflection fluorescence (TIRF), spectrum-resolved single-molecule/particle imaging for multiplex assay, and label-free scattering detection in an interference mode for virus or protein counting. The mechanisms, advantages, challenges, and prospects of adopting optical microscopy for single-molecule detection are discussed.
TRAC-TRENDS IN ANALYTICAL CHEMISTRY
(2023)
Article
Chemistry, Physical
Michael J. Boyle, Yale E. Goldman, Russell J. Composto
Summary: Interferometric scattering microscopy (iSCAT) is a label-free optical microscopy technique used for imaging individual nano-objects. A mask R-CNN algorithm is developed to improve particle detection in iSCAT experiments by differentiating between background and particle signals. The inclusion of representative experimental backgrounds in the training dataset improves the performance of the mask R-CNN and reduces false positives.
JOURNAL OF PHYSICAL CHEMISTRY B
(2023)
Article
Engineering, Mechanical
Hywel Davies, Midhat Talibi, Andrea Ducci, Nishant Parsania, Ramanarayanan Balachandran
Summary: This paper proposes an effective Lagrangian Planar Interferometric Tracking (PIT) processor to track the size and path of multiple droplets. It analyzes the sources of errors in droplet measurement and assesses their impact on the final results. The feasibility of the method is validated through experiments and comparison with model predictions.
EXPERIMENTS IN FLUIDS
(2022)
Article
Physics, Multidisciplinary
Martin Silhavik, Prabhat Kumar, Zahid Ali Zafar, Martin Misek, Martin Cicala, Marek Piliarik, Jiri Cervenka
Summary: Graphene aerogel exhibits anomalous superelastic behavior and can withstand high compressive and tensile strains. A quantitative origami model is developed to describe its stress-strain behavior.
COMMUNICATIONS PHYSICS
(2022)
Article
Biochemistry & Molecular Biology
Rim Baccouch, Estelle Rascol, Kaja Stoklosa, Isabel D. Alves
Summary: GPCRs are membrane proteins that sense extracellular signals and activate intracellular signaling pathways. Their structure and function are influenced by the surrounding lipid environment and membrane properties. Lipids can act as important cofactors and play a role in GPCR activity.
BIOPHYSICAL CHEMISTRY
(2022)
Article
Multidisciplinary Sciences
Estelle Rascol, Anouk Dufourquet, Rim Baccouch, Pierre Soule, Isabel D. Alves
Summary: A novel experimental procedure using microscale thermophoresis (MST) directly from cell membrane fragments was developed to determine ligand binding affinities to membrane proteins. The procedure overcame the challenge of purification and successfully determined the concentration and binding affinity of the dopamine D2 receptor.
SCIENTIFIC REPORTS
(2022)
Review
Biochemistry & Molecular Biology
Rim Baccouch, Yarong Shi, Emilie Vernay, Marion Mathelie-Guinlet, Nada Taib-Maamar, Sandrine Villette, Cecile Feuillie, Estelle Rascol, Philippe Nuss, Sophie Lecomte, Michael Molinari, Galya Staneva, Isabel D. Alves
Summary: The lipid composition and balance in cellular membranes can be influenced by various factors, including aging, pathologies, and diets. In individuals with psychiatric disorders, such as schizophrenia, the cell membranes have been found to be deficient in polyunsaturated fatty acids (PUFAs), which could impact the interaction of medications and the activation of receptors embedded in the lipid membrane. Understanding how changes in PUFA levels affect membrane properties is crucial.
BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES
(2023)
Article
Polymer Science
Esra Aydinlioglu, Mona Abdelghani, Gaelle Le Fer, Jan C. M. van Hest, Olivier Sandre, Sebastien Lecommandoux
Summary: Two pairs of oppositely charged PEO-b-poly(amino acid) copolymers were synthesized and self-assembled into stable polyion complexes (PICsomes) with high potential as biocompatible nanocarriers for RNA interference. These PICsomes exhibited good stability even in high salinity media due to hydrophobic interactions between the phenylalanine residues. They successfully loaded small interfering RNA (siRNA) and showed minimal cell cytotoxicity while demonstrating superior gene silencing efficacy compared to free siRNA and a standard lipofectamine-siRNA complex.
MACROMOLECULAR CHEMISTRY AND PHYSICS
(2023)
Article
Biochemistry & Molecular Biology
Marie-Lise Jobin, Veronique De Smedt-Peyrusse, Fabien Ducrocq, Rim Baccouch, Asma Oummadi, Maria Hauge Pedersen, Brian Medel-Lacruz, Maria-Florencia Angelo, Sandrine Villette, Pierre Van Delft, Laetitia Fouillen, Sebastien Mongrand, Jana Selent, Tarson Tolentino-Cortez, Gabriel Barreda-Gomez, Stephane Gregoire, Elodie Masson, Thierry Durroux, Jonathan A. Javitch, Ramon Guixa-Gonzalez, Isabel D. Alves, Pierre Trifilieff
Summary: Increasing evidence suggests a connection between lipid metabolism and mental health, particularly in relation to polyunsaturated fatty acids (PUFAs). Recent findings show that PUFA levels in the brain are linked to dopamine transmission, a key system involved in psychiatric symptoms. However, the underlying mechanisms of this relationship are still unclear.
MOLECULAR PSYCHIATRY
(2023)
Article
Chemistry, Multidisciplinary
Clemence Schvartzman, Hang Zhao, Emmanuel Ibarboure, Vusala Ibrahimova, Elisabeth Garanger, Sebastien Lecommandoux
Summary: In response to osmotic stress, cells release excess water to avoid bursting and death. By encapsulating functional elastin-like polypeptide (ELP) biomacromolecular conjugates into lipid vesicles using a microfluidic system, researchers mimic the formation of membraneless organelles induced by water expulsion. The local concentration increase and decrease in cloud point temperature (T-cp) of ELP bioconjugates due to hypertonic shock lead to the formation of coacervates, which mimic cellular stress-induced organelle assemblies. This dynamic response to osmotic stress can increase the local concentration and accelerate the enzymatic reaction.
ADVANCED MATERIALS
(2023)
Article
Pharmacology & Pharmacy
Anouk Martin, Pierre Lalanne, Amelie Weber-Vax, Angela Mutschler, Sebastien Lecommandoux
Summary: The self-assembly of PEG-b-PTMC copolymers into vesicles, also known as polymersomes, was evaluated using microfluidic systems. Two microfluidic chips with different flow regimes were used to investigate the impact of process conditions on vesicle formation. A solvent exchange approach was developed to allow direct use of the polymersomes in biological evaluation. The size of the polymersomes was influenced by the total flow rate and copolymer concentration, but not by the organic/aqueous solvent ratio.
INTERNATIONAL JOURNAL OF PHARMACEUTICS
(2023)
Article
Biochemistry & Molecular Biology
Chloe Grazon, Elisabeth Garanger, Pierre Lalanne, Emmanuel Ibarboure, James E. Galagan, Mark W. Grinstaff, Sebastien Lecommandoux
Summary: Polymeric micelles based on natural diblocks, such as elastin-like polypeptide (ELP) and oligonucleotide (ON), have advantageous properties in terms of molecular recognition, biocompatibility, and biodegradability. This study reports a straightforward synthesis of ON-b-ELP diblock bioconjugates through copper-catalyzed azide-alkyne cycloaddition. The resulting micelles self-assemble above their critical micelle temperature (CMT) to form stable structures, and they retain their stability and temperature sensitivity when binding with proteins.
Article
Polymer Science
Pedro Salas-Ambrosio, Antoine Tronnet, Mostafa Badreldin, Sifan Ji, Sebastien Lecommandoux, Simon Harrisson, Pierre Verhaeghe, Colin Bonduelle
Summary: This report provides a comprehensive study on the contribution of the N-alkyl group to the synthesis of NNCA and its reactivity in polymerization reactions. We found that electron-donating groups can enhance the kinetic rates of polymerization reactions.
Article
Materials Science, Biomaterials
Manon Leveque, Ye Xiao, Laura Durand, Louise Masse, Elisabeth Garanger, Sebastien Lecommandoux
Summary: This study focuses on the design and synthesis of bioactive and thermo-responsive bioconjugates, which can self-assemble into nanoparticles with different properties. By conducting a comprehensive physico-chemical study, the researchers identified the factors influencing the properties of these nanoparticles and proposed a versatile and simple design for creating bioactive nanoparticles.
BIOMATERIALS SCIENCE
(2022)
Article
Chemistry, Multidisciplinary
Chloe Grazon, Margaret Chern, Patrick Lally, R. C. Baer, Andy Fan, Sebastien Lecommandoux, Catherine Klapperich, Allison M. Dennis, James E. Galagan, Mark W. Grinstaff
Summary: This study systematically compared the effects of organic and inorganic dyes in biosensors, as well as the impact of the position of FRET donors or acceptors on biomolecular components on sensor performance. By examining different biosensor configurations through experimental and computational approaches, researchers identified key molecular parameters influencing sensor performance and provided design guidelines for future intermolecular biosensors based on FRET.
Article
Chemistry, Physical
Meriem Er-Rafik, Khalid Ferji, Jerome Combet, Olivier Sandre, Sebastien Lecommandoux, Marc Schmutz, Jean-Francois Le Meins, Carlos M. Marques
Summary: Recently, there has been increasing concern about the health risks associated with nanotechnologies, as it has been discovered that nanoparticles can reach the interior of cells and potentially disrupt cell membranes. This study reveals that small nanoparticles can tear lipid membranes, providing insight into the mechanisms by which nanoparticles can compromise membrane integrity.
