scholarly journals Emergence of uniform linearly-arranged micro-droplets entrapping DNA and living cells through water/water phase-separation

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Mayu Shono ◽  
Ritsuki Ito ◽  
Fumika Fujita ◽  
Hiroki Sakuta ◽  
Kenichi Yoshikawa
Keyword(s):  
Phase Separation ◽  
Polymer Solution ◽  
Living Cells ◽  
Biological Species ◽  
Water Phase ◽  
Dna Molecules ◽  
Glass Capillary ◽  
Mechanical Mixing ◽  
Simple Method ◽  
Binary Polymer

AbstractLiving cells maintain their lives through self-organization in an environment crowded with a rich variety of biological species. Recently, it was found that micro-droplets containing biomacromolecules, which vary widely in size, are generated accompanied by water/water phase-separation by simple mechanical mixing of an aqueous solution with binary polymers. Here, we report that cell-sized droplets of nearly the same size are generated as a linear array within a glass capillary upon the introduction of a binary polymer solution of polyethylene glycol (PEG) and dextran (DEX). Interestingly, when DNA molecules are added to the polymer solution, stable droplets entrapping DNA molecules are obtained. Similarly, living cells are entrapped spontaneously for the linearly-arranged cell-sized droplets. This simple method for generating micro-droplets entrapping DNA and also living cells is expected to stimulate further study on the self-construction of protocells and micro organoids.

scholarly journals A computational study of phase separation in polymer solutions under a double quench

2021 ◽  
Author(s):  
Ehsan Hosseini
Keyword(s):  
Phase Separation ◽  
Polymer Solution ◽  
Spinodal Decomposition ◽  
Computational Study ◽  
Stable State ◽  
Thermal Quenching ◽  
Nucleation And Growth ◽  
Two Dimensions ◽  
Numerical Work ◽  
Binary Polymer

Polymer-dispersed liquid crystals (PDLCs) are a relatively new class of materials used for many applications ranging from switchable windows to projection displays. PDLSs are formed by spinodal decomposition induced by thermal quenching or polymerization. The objective of the present study is to introduce a new mechanism of phase separation in a binary polymer solution and develop a mathematical model and computer simulation to describe the phase separation during the early and intermediate stages of nucleation and growth and spinodal decomposition induced by thermal double quenching. The growth equilibrium limits of phase separation as well as phase transition are calculated by taking into consideration the Flory-Huggins theory for the free energy of mixing. A two step quench is modeled using Cahn-Hilliard theory for asymmetric binary polymer solution which is quenched from a stable state in the one-phase region to a metastable region where nucleation and growth occurs. The solution is allowed to coarsen for different time periods before a second quench was applied to a point further inside the phase diagram. The numerical results in two dimensions replicate the experimental and numerical work that has been recently done and published.

scholarly journals A computational study of phase separation in polymer solutions under a double quench

2021 ◽  
Author(s):  
Ehsan Hosseini
Keyword(s):  
Phase Separation ◽  
Polymer Solution ◽  
Spinodal Decomposition ◽  
Computational Study ◽  
Stable State ◽  
Thermal Quenching ◽  
Nucleation And Growth ◽  
Two Dimensions ◽  
Numerical Work ◽  
Binary Polymer

Polymer-dispersed liquid crystals (PDLCs) are a relatively new class of materials used for many applications ranging from switchable windows to projection displays. PDLSs are formed by spinodal decomposition induced by thermal quenching or polymerization. The objective of the present study is to introduce a new mechanism of phase separation in a binary polymer solution and develop a mathematical model and computer simulation to describe the phase separation during the early and intermediate stages of nucleation and growth and spinodal decomposition induced by thermal double quenching. The growth equilibrium limits of phase separation as well as phase transition are calculated by taking into consideration the Flory-Huggins theory for the free energy of mixing. A two step quench is modeled using Cahn-Hilliard theory for asymmetric binary polymer solution which is quenched from a stable state in the one-phase region to a metastable region where nucleation and growth occurs. The solution is allowed to coarsen for different time periods before a second quench was applied to a point further inside the phase diagram. The numerical results in two dimensions replicate the experimental and numerical work that has been recently done and published.

Phase separation in binary polymer solution: Gelatin/Poly(ethylene glycol) system

2014 ◽  
Vol 200 ◽  
pp. 2-6 ◽  
Author(s):  
Miho Yanagisawa ◽  
Yutaro Yamashita ◽  
Sada-atsu Mukai ◽  
Masahiko Annaka ◽  
Masayuki Tokita
Keyword(s):  
Phase Separation ◽  
Ethylene Glycol ◽  
Polymer Solution ◽  
Poly Ethylene Glycol ◽  
Binary Polymer ◽  
Poly Ethylene

scholarly journals Higher-order structure of DNA determines its positioning in cell-size droplets under crowded conditions

PLoS ONE ◽  
2021 ◽  
Vol 16 (12) ◽  
pp. e0261736
Author(s):  
Takashi Nishio ◽  
Yuko Yoshikawa ◽  
Kenichi Yoshikawa
Keyword(s):  
Phase Separation ◽  
Polymer Solution ◽  
Underlying Mechanism ◽  
Living Cells ◽  
Higher Order ◽  
Chemical Mechanism ◽  
Order Structure ◽  
Aqueous Polymer ◽  
Aqueous Polymer Solution ◽  
Specific Localization

Background It is becoming clearer that living cells use water/water (w/w) phase separation to form membraneless organelles that exhibit various important biological functions. Currently, it is believed that the specific localization of biomacromolecules, including DNA, RNA and proteins in w/w microdroplets is closely related to their bio-activity. Despite the importance of this possible role of micro segregation, our understanding of the underlying physico-chemical mechanism is still unrefined. Further research to unveil the underlying mechanism of the localization of macromolecules in relation to their steric conformation in w/w microdroplets is needed. Principal findings Single-DNA observation of genome-size DNA (T4 GT7 bacteriophage DNA; 166kbp) by fluorescence microscopy revealed that DNAs are spontaneously incorporated into w/w microdroplets generated in a binary aqueous polymer solution with polyethylene glycol (PEG) and dextran (DEX). Interestingly, DNAs with elongated coil and shrunken conformations exhibit Brownian fluctuation inside the droplet. On the other hand, tightly packed compact globules, as well as assemblies of multiple condensed DNAs, tend to be located near the interface in the droplet. Conclusion and significance The specific localization of DNA molecules depending on their higher-order structure occurs in w/w microdroplet phase-separation solution under a binary aqueous polymer solution. Such an aqueous solution with polymers mimics the crowded conditions in living cells, where aqueous macromolecules exist at a level of 30–40 weight %. The specific positioning of DNA depending on its higher-order structure in w/w microdroplets is expected to provide novel insights into the mechanism and function of membraneless organelles and micro-segregated particles in living cells.

scholarly journals Phase Separation of a Model Binary Polymer Solution in an External Field†

2006 ◽  
Vol 110 (8) ◽  
pp. 3661-3665 ◽  
Author(s):  
Chris I. Addison ◽  
Pierre-Arnaud Artola ◽  
Jean-Pierre Hansen ◽  
Ard A. Louis
Keyword(s):  
Phase Separation ◽  
External Field ◽  
Polymer Solution ◽  
Binary Polymer

Phase separation and physico-chemical processes at microscopic and macroscopic levels in MWCNT laden polymer blends using a unique droplet based architecture

2017 ◽  
Vol 19 (36) ◽  
pp. 24961-24970 ◽  
Author(s):  
Binita Pathak ◽  
Goutam Prasanna Kar ◽  
Suryasarathi Bose ◽  
Saptarshi Basu
Keyword(s):  
Phase Separation ◽  
Polymer Blends ◽  
Polymer Solution ◽  
Heating Rate ◽  
Chemical Processes ◽  
Binary Polymer ◽  
Physico Chemical ◽  
Phase Separation Behavior ◽  
Contact Free ◽  
Separation Behavior

We propose a unique contact-free droplet based architecture to alter the phase separation behavior in binary polymer solution (PS/PVME in toluene) by tuning the external heating rate and concentration of added MWCNT particles.

Phase Separation Gives Rise To Nanoparticle Ring Formation

2003 ◽  
Vol 58 (7-8) ◽  
pp. 392-396
Author(s):  
L.V. Govor ◽  
J. Parisi ◽  
G. H. Bauer
Keyword(s):  
Thin Film ◽  
Phase Separation ◽  
Polymer Solution ◽  
Particle Diameter ◽  
Bottom Layer ◽  
Polymer Thin Film ◽  
Self Assembling ◽  
Binary Polymer ◽  
Ring Diameter ◽  
Ultrathin Polymer Films

We report on the formation of self-assembled rings of CoPt3 nanoparticles in ultrathin polymer films (ring diameter about 1 μm, particle diameter 6 nm). The polymer thin film was formed by wetting a polymer solution on the surface of water. The process of self-assembling turns out to result from phase separation of the binary polymer solution film used, the subsequent dewetting of the top layer, and its decomposition into droplets on the surface of the bottom layer.

Capturing Protein Droplets: Label-free Visualization and Detection of Protein Liquid-Liquid Phase Separation with an Aggregation-Induced Emission Fluorogen

2021 ◽  
Author(s):  
Yan-Mei Li ◽  
Chu-Qiao Liang ◽  
Lin Wang ◽  
Yun-Yi Luo ◽  
Qian-Qian Li
Keyword(s):  
Phase Separation ◽  
Liquid Phase ◽  
Liquid Phase Separation ◽  
New Method ◽  
Label Free ◽  
Simple Method ◽  
Aggregation Induced Emission ◽  
Liquid Liquid Phase Separation

We developed a new method for protein droplet visualization by means of a droplet probe (DroProbe) based on an aggregation-induced emission (AIE) fluorogen. A simple method for viscosity comparison of...

Sign in / Sign up

Export Citation Format

Share Document