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

Abstract

Living 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.

Periodic Alignment of Binary Droplets via a Microphase Separation of a Tripolymer Solution under Tubular Confinement

“…This pattern, emerging from the phase separation of two types of hydrophilic polymers in water within a capillary, organizes itself. 31,32 In this present study, we demonstrate that a periodic alignment of binary microdroplets, each surrounded by a different polymer solution, arises from the phase separation of an aqueous tripolymer solution in a capillary. Recently, in the studies concerning coacervate formation, generation of various specific spatial patterns with polydispersity have been reported.…”

“…Conversely, our recent findings reveal the spontaneous alignment of uniformly sized microdroplets within a quasi-one-dimensional confinement (quasi-1D). This pattern, emerging from the phase separation of two types of hydrophilic polymers in water within a capillary, organizes itself. , In this present study, we demonstrate that a periodic alignment of binary microdroplets, each surrounded by a different polymer solution, arises from the phase separation of an aqueous tripolymer solution in a capillary. Recently, in the studies concerning coacervate formation, generation of various specific spatial patterns with polydispersity have been reported. ,− It is particularly notable that the periodic pattern formation of our study occurs in a thermodynamically closed system, which is in contrast to the pattern formation observed in thermodynamically open systems, such as the reaction-diffusion system responsible for Turing patterns. − In essence, the spatial periodic pattern in our system is kinetically stable, persisting without the need for a continuous input of energy or materials, distinguishing it from the dynamics of patterning in reaction-diffusion systems.…”

The screening, identification, design and clinical application of tumor-specific neoantigens for TCR-T cells

“…Activated T cells were detected and analyzed by a microfluidic system, and the TCR was cloned. The technique is based on T-cell functional analysis, which reduces nonspecific findings [ 250 , 251 ]. However, the number of T cells in each analysis was limited, and the system complexity was high.…”

Spontaneous Formation of Uniform Cell‐Sized Microgels through Water/Water Phase Separation

“…To solve these issues, we have previously reported that ATPS of confined polymer blends can be utilized for the size control of w/w droplets. [ 31 ] The phase separation of PEG/DEX solution inside a glass capillary produces cell‐sized droplets with approximately uniform size through spinodal decomposition [ 32 ] within the confinement of quasi‐1D. We used this ATPS method to produce uniform cell‐sized microgels.…”