The Physical Theory of Single-Molecule Measurements in Dilute Liquids and Live Cells

What is it about?

What do the approaches of Single-Molecule Localization Microscopy/Nanoscopy/ Spectroscopy and Laser Scanning Microscopy or Single-Molecule Image Analysis as well as (temporally unlimited) Single-Molecule Tracking in liquids or live cells without immobilization on artificial or biological surfaces or without significant hydrodynamic flow tell us about a single molecule? The answer is: NOTHING !! Regarding the sections/cited papers on "Single-molecule localization imaging", single-molecule localization-based super-resolution microscopy, single-molecule localization microscopy, and "Perspectives" of the Review Article "Advanced imaging and labelling methods to decipher brain cell organization and function" by Daniel Choquet, Matthieu Sainlos & Jean-Baptiste Sibarita, Nature Reviews Neuroscience (2021), Published: 12 March 2021, here is the physical theory on it: Have a deeper look at the Theory of Single-Molecule Detection of one and the same molecule (the individual molecule) in dilute liquids and single live cells without significant hydrodynamic flow or immobilization on artificial or biological surfaces/membranes: The Single-Molecule Time Resolution in microsopy/nanoscopy (super-resolution microscopy)/ spectroscopy: https://pubmed.ncbi.nlm.nih.gov/23369193/ https://pubmed.ncbi.nlm.nih.gov/25543662/ and https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3195905/ Tom Laue, Emeritus Professor UNH, Durham, New Hampshire, United States, wrote: I agree with you. My posts (see below) are merely a way to get students and non-biophysicists to understand what occurs during an interaction. I will be getting into the ergodic hypothesis later in this series where it will be clear that 'single molecule' behavior shouldn't be extrapolated to all molecule behavior. Forwarded Mar 8 at 3:51 PM POST: Fun facts: Molecular interactions So you have diffused to ~1 nanometer from a another protein. Your encounter has begun, and in roughly a nanosecond you will either touch the surface of the other protein, or be repelled by it. What happens in this nanosecond will occupy several posts... at the pace this is going, the pandemic will be waning when you do or do not touch. At 1 nm, you will experience the charge-charge interaction with, B, the name we'll assign to the other protein (you, of course being superior, are A). The interaction takes the form of a potential energy, U. The strength of U = QA*QB/Dr, where, QA is your net charge, QB is the net charge on B, r is the distance to the surface of B and D is the dielectric constant of the solvent (~80 for water at room temperature). Now this is a rough approximation for several reasons, each of which we need to consider. We will spend some time with each over the next few posts. We'll start with using the surface-to-surface distance... a glaringly poor choice from a physicists point of view.

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Photo by Terry Vlisidis on Unsplash

Photo by Terry Vlisidis on Unsplash

Why is it important?

Why is this theory so attractive? There is direct and simple connection with measurements. This connection is based on the diffusion times of molecules. In fact, all conditions are only properties of the stochastic nature of diffusion times of single molecules. In the original paper where the equations and the concentration dependence of this modern theory of single-molecule detection at the level of the individual molecule, i.e., one and the same molecule, was formulated for the very first time, the derivations of the equations, remarks and explanations were given to justify the experimental conditions (criteria 1 to 3, the single-molecule time resolution Tm is the criterion 4 (Tm is the meaningful time for measuring just one and the same molecule in dilute liquids and live cells without immobilization on artificial surfaces or biological membranes as well as without significant hydrodynamic flow). In this theory, diffusion times are directly linked to selfsame molecule likelihood estimators as a consequence of the stochastic analysis of the thermodynamic system considered. The language of stochastic thermodynamics is the main advantage of the theory of single-molecule detection at the level of the individual molecule. The deductive reasoning does not require any data. This is the effectiveness of the formulas with which I precisely describe the real conditions, some of which are far beyond what can be observed with current technologies. In other words, the theory and its natural laws have practical uses and consequences. The advantages of the physical Theory are evident: The 'SINGLE-MOLECULE DEMON' (single-molecule ratchet) in IMAGING/MICROSCOPY/SUPER-RESOLUTION MICROSCOPY (NANOSCOPY) and SPECTROSCOPY of Dilute Liquids and Live Cells that is The 'SINGLE-MOLECULE DEMON' (single-molecule ratchet) in Single-Molecule Localization Microscopy/Nanoscopy (Super-Resolution Microscopy)/Spectroscopy and Single-Molecule Laser Scanning Microscopy or Single-Molecule Image Analysis in liquids or live cells without immobilization on artificial or biological surfaces or without significant hydrodynamic flow •https://www.growkudos.com/publications/10.2174%252F138920111795470949/reader Zeno. The thermodynamic Single-Molecule DEMON: How to avoid him in the measurements of dilute liquids and live cells without immobilization or flow: https://ajtm.journals.publicknowledgeproject.org/index.php/ajtm/article/view/1408

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