scholarly journals Scalable Fabrication of 3D Structured Microparticles Using Induced Phase Separation

2021 ◽  
Author(s):  
Sohyung Lee ◽  
Joe de Rutte ◽  
Robert Dimatteo ◽  
Doyeon Koo ◽  
Dino Di Carlo
Keyword(s):  
Phase Separation ◽  
Phase System ◽  
Cell Secretion ◽  
Two Phase ◽  
Hollow Shell ◽  
Hydrogel Microparticles ◽  
Trade Offs ◽  
Shell Particles ◽  
Scalable Production ◽  
Formation Phase

Microparticles with defined shapes and spatial chemical modification can enable new opportunities to interface with cells and tissues at the cellular scale. However, conventional methods to fabricate shaped microparticles have trade-offs between the throughput of manufacture and precision of particle shape and chemical functionalization. Here, we achieved scalable production of hydrogel microparticles at rates of greater than 40 million/hour with localized surface chemistry using a parallelized step emulsification device and temperature-induced phase-separation. The approach harnesses a polymerizable polyethylene glycol (PEG) and gelatin aqueous-two phase system (ATPS) which conditionally phase separates within microfluidically-generated droplets. Following droplet formation, phase separation is induced and phase separated droplets are subsequently crosslinked to form uniform crescent and hollow shell particles with gelatin functionalization on the boundary of the cavity. The gelatin localization enabled deterministic cell loading in nanoliter-sized crescent-shaped particles, which we refer to as nanovials, with cavity dimensions tuned to the size of cells. Loading on nanovials also imparted improved cell viability during analysis and sorting using standard fluorescence activated cell sorters, presumably by protecting cells from shear stress. This localization effect was further exploited to selectively functionalize capture antibodies to nanovial cavities enabling single-cell secretion assays with reduced cross-talk in a simplified format.

Transmission Electron Microscopy (TEM) Observations of Phase-Separations of Gamma-Prime Precipitates in Ni-Al-Fe and Ni-Si-Fe Ternary Alloys

2007 ◽  
Vol 26-28 ◽  
pp. 1311-1314 ◽  
Author(s):  
M. Senga ◽  
H. Kumagai ◽  
Tomokazu Moritani ◽  
Minoru Doi
Keyword(s):  
Phase Separation ◽  
Volume Fraction ◽  
Heating Temperature ◽  
Ternary Alloys ◽  
Phase System ◽  
Precipitate Phase ◽  
Two Phase ◽  
Gamma Prime ◽  
Transmission Electron ◽  
The Difference

In Ni-13.0at%Si-3.1at%Fe alloy, when γ/γ’ two-phase microstructure formed at 1123 K is isothermally heated at 923 K which is lower than the temperature where the initial γ/γ’ microstructure forms, the phase-separation of γ/γ’ precipitate phase occurs and γ particles newly appear in each cuboidal γ’ precipitate. While in Ni-10.2at%Al-10.8at%Fe alloy, when γ/γ’ two-phase microstructure formed at 1023 K is isothermally heated at 1123 K which is higher than the temperature where the initial γ/γ’ microstructure forms, the phase-separation of γ’ precipitate phase takes place and γ particles newly appear in each cuboidal γ’ precipitate. Such appearance of new γ particles in γ’ precipitates can be explained by the difference in the volume fraction of γ phase that should exist in the γ/γ’ two-phase system depending on the heating temperature.

Upflow Anaerobic Sludge Digestion in a Phase Separation System

1993 ◽  
Vol 28 (7) ◽  
pp. 133-138 ◽  
Author(s):  
Hsin-Yi Lin ◽  
Chaio-Fuei Ouyang
Keyword(s):  
Phase Separation ◽  
Gas Production ◽  
Anaerobic Sludge ◽  
Phase System ◽  
Volatile Acid ◽  
Two Phase ◽  
Cell Biomass ◽  
Sludge Digestion ◽  
Methane Production Rate ◽  
The One

This paper aims to expand the knowledge about methods for improving the rate of solids hydrolysis, volatile acid formation and methane gas production. It studies the effects of phase separation and operational modes on the performance of the process. Two systems were investigated. The two-phase system consisted of a CSTR acid-phase digester and an upflow methane-phase digester, the one-phase system comprised of an upflow anaerobic digester. In order to provide optimal contact conditions and recycle liberated indigenous enzymes or cell biomass fractions, continuous recycling of the effluent sludges to the sludge bed of the reactor was used. In general, the nonbiodegradable portion of the substrates contained in the mixed sludges was found to be about 45% on the basis of TVS. The TVS reduction of the two-phase system was 53%, this is higher than in the one-phase system. Methane production rate and methane content were 0.351 l/g TVS added and 66.6%, respectively.

scholarly journals Integrated Clarification and Purification of Monoclonal Antibodies by Membrane Based Separation of Aqueous Two-Phase Systems

Antibodies ◽  
2019 ◽  
Vol 8 (3) ◽  
pp. 40 ◽  
Author(s):  
Thomas Kruse ◽  
Axel Schmidt ◽  
Markus Kampmann ◽  
Jochen Strube
Keyword(s):  
Monoclonal Antibodies ◽  
Phase Separation ◽  
Chinese Hamster ◽  
Contact Angles ◽  
Cell Protein ◽  
Phase System ◽  
Separation Performance ◽  
Downstream Process ◽  
Two Phase ◽  
Cultivation Broth

Therapeutic monoclonal antibodies (mAb) are used for the treatment of numerous serious diseases, which have led to an increasing demand over the last decades. Increased cell density and mAb titer of the cultivation broth lead to great challenges for the subsequent clarification and capture operations in the downstream process. As an alternative approach to the conventional downstream process, a selective mAb extraction via an aqueous two-phase system (ATPS) directly from the cultivation broth of a mAb producing industrial relevant chinese hamster ovary (CHO) cell line was investigated. An efficient purification of the mAb was accomplished by the ATPS composition. The phase separation was realized by a newly developed membrane based phase separator. Moreover, a complete cell removal was integrated into this process by the used membrane. A selectivity between both phases was achieved by membrane modification. Yields up to 93% in the light phase and removal of process related impurities were obtained after aqueous two-phase extraction (ATPE). Phase separation performance as well as contact angles on the membrane were characterized for different ATPS. ATPE directly from the cultivation broth in combination with the new membrane based phase separation led to a mAb yield of 78% with a simultaneous reduction of deoxyribonucleic acid (DNA) and host cell protein (HCP) load.

Phase-Separation of B2 Precipitates in an Fe-Ni-Al Alloy

2010 ◽  
Vol 638-642 ◽  
pp. 2274-2278 ◽  
Author(s):  
Yasuhiro Kuno ◽  
Yasuo Nakane ◽  
Takao Kozakai ◽  
Minoru Doi ◽  
Junji Yamanaka ◽  
...  
Keyword(s):  
Free Energy ◽  
Phase Separation ◽  
Volume Fraction ◽  
Heating Temperature ◽  
Phase System ◽  
Al Alloy ◽  
Two Phase ◽  
Chemical Free Energy ◽  
The Difference ◽  
The Individual

When Fe-10.3mol%Ni-14.3mol%Al alloy is heated at 1173 K for 8.64104 s, a number of B2 precipitates are dispersed in the A2 matrix. When the two-phase microstructure of A2+B2 is aged at 973 K, the phase-separation of B2 precipitate particles takes place to form a new A2 phase in each B2 particle. In the course of further ageing at 973 K, the new A2 phase grows but decreases in number, and finally only one A2 particle is left in the individual B2 particles. The appearance of new A2 phase in each B2 precipitate is due to the difference in the volume fraction of A2 phase that should exist in A2+B2 two-phase system depending on the heating temperature: i.e., the phase-separation of B2 precipitates starts with the aid of chemical free energy.

scholarly journals More than just oil droplets in water: surface tension and viscosity of protein condensates quantified by micropipette aspiration

2021 ◽  
Author(s):  
Huan Wang ◽  
Fleurie M Kelley ◽  
Dragomir Milovanovic ◽  
Benjamin S Schuster ◽  
Zheng Shi
Keyword(s):  
Surface Tension ◽  
Phase Separation ◽  
Liquid Phase ◽  
Material Properties ◽  
Water Surface ◽  
Phase System ◽  
Surface Wetting ◽  
Two Phase ◽  
Quantitative Studies ◽  
Liquid Liquid Phase Separation

The material properties of biomolecular condensates play pivotal roles in many biological and pathological processes. Despite the rapid increase in the number of biomolecules identified that undergo liquid-liquid phase separation (LLPS), quantitative studies of the resulting condensates have been severely lagging behind. Here, we develop a micropipette-based technique, which uniquely allows quantifications of both the surface tension and viscosity of biomolecular condensates, independent of labeling and surface wetting effects. We demonstrate the accuracy and versatility of this technique by measuring condensates of LAF-1 RGG domains and a polymer-based aqueous two-phase system (ATPS). We anticipate this technique will be widely applicable to biomolecular condensates and will resolve several limitations regarding current approaches.

Phase Diagram of Aqueous Two-Phase System (ATPS) Composed of Polyethylene Glycol (PEG) and Gelatin

2012 ◽  
Vol 554-556 ◽  
pp. 286-294 ◽  
Author(s):  
Chao Ma ◽  
Xiao Dong Chen ◽  
Yin Qiu Kong ◽  
Li Ming Che
Keyword(s):  
Phase Diagram ◽  
Aqueous Solution ◽  
Phase Separation ◽  
Polyethylene Glycol ◽  
Solid Content ◽  
Phase System ◽  
Dense Phase ◽  
Two Phase ◽  
Aqueous Two Phase System ◽  
First Time

Phase diagram of aqueous two-phase system (ATPS) composed of polyethylene glycol (PEG) and gelatin is of paramount importance for the application of such system in microencapsulation of bioactive compounds. Phase separation of PEG/gelatin aqueous solution was investigated in the present work and the phase diagram of resultant ATPS was reported for the first time. The results show that phase separation will happen if the solid content of PEG/gelatin aqueous solution is higher than a critical value, resulting in an ATPS. The resultant ATPS consists of a low-density phase enriched in PEG and a dense phase enriched in gelatin. The phase compositions of the resultant ATPS were determined accurately using the method developed. The phase diagrams obtained show that higher solid content is required for the phase separation of PEG10,000/gelatin aqueous solution when compared with that of PEG20,000/gelatin one. And PEG is found to be more hydrophilic when compared with gelatin.

scholarly journals Segregation Behavior of Polysaccharide–Polysaccharide Mixtures—A Feasibility Study

Gels ◽  
2019 ◽  
Vol 5 (2) ◽  
pp. 26
Author(s):  
Benjamin Zeeb ◽  
Theresa Jost ◽  
David Julian McClements ◽  
Jochen Weiss
Keyword(s):  
Phase Separation ◽  
Flow Behavior ◽  
Phase Segregation ◽  
Calcium Sensitivity ◽  
Phase System ◽  
Two Phase ◽  
Lower Phase ◽  
Product Formulation ◽  
Internal Structures ◽  
Phase Separation Behavior

The segregative phase separation behavior of biopolymer mixtures composed entirely of polysaccharides was investigated. First, the electrical, optical, and rheological properties of alginate, modified beet pectin, and unmodified beet pectin solutions were characterized to determine their electrical charge, molecular weight, solubility, and flow behavior. Second, suitable conditions for inducing phase segregation in biopolymer mixtures were established by measuring biopolymer concentrations and segregation times. Third, alginate–beet pectin mixtures were blended at pH 7 to promote segregation and the partitioning of the biopolymers between the upper and lower phases was determined using UV–visible spectrophotometry, colorimetry, and calcium sensitivity measurements. The results revealed that phase separation depended on the overall biopolymer concentration and the degree of biopolymer hydrophobicity. A two-phase system could be formed when modified beet pectins (DE 68%) were used but not when unmodified ones (DE 53%) were used. Our measurements demonstrated that the phase separated systems consisted of a pectin-rich lower phase and an alginate-rich upper phase. These results suggest that novel structures may be formed by utilization of polysaccharide–polysaccharide phase separation. By controlling the product formulation and processing conditions it may therefore be possible to fabricate biopolymer particles with specific dimensions, shapes, and internal structures.

scholarly journals A stepwise mechanism for aqueous two-phase system formation in concentrated antibody solutions

2019 ◽  
Vol 116 (32) ◽  
pp. 15784-15791 ◽  
Author(s):  
Bradley A. Rogers ◽  
Kelvin B. Rembert ◽  
Matthew F. Poyton ◽  
Halil I. Okur ◽  
Amanda R. Kale ◽  
...  
Keyword(s):  
Activation Energy ◽  
Phase Separation ◽  
Temperature Gradient ◽  
Apparent Activation Energy ◽  
Droplet Growth ◽  
Phase System ◽  
Two Phase ◽  
Aqueous Two Phase System ◽  
Kinetics Of ◽  
Spinodal Region

Aqueous two-phase system (ATPS) formation is the macroscopic completion of liquid–liquid phase separation (LLPS), a process by which aqueous solutions demix into 2 distinct phases. We report the temperature-dependent kinetics of ATPS formation for solutions containing a monoclonal antibody and polyethylene glycol. Measurements are made by capturing dark-field images of protein-rich droplet suspensions as a function of time along a linear temperature gradient. The rate constants for ATPS formation fall into 3 kinetically distinct categories that are directly visualized along the temperature gradient. In the metastable region, just below the phase separation temperature, Tph, ATPS formation is slow and has a large negative apparent activation energy. By contrast, ATPS formation proceeds more rapidly in the spinodal region, below the metastable temperature, Tmeta, and a small positive apparent activation energy is observed. These region-specific apparent activation energies suggest that ATPS formation involves 2 steps with opposite temperature dependencies. Droplet growth is the first step, which accelerates with decreasing temperature as the solution becomes increasingly supersaturated. The second step, however, involves droplet coalescence and is proportional to temperature. It becomes the rate-limiting step in the spinodal region. At even colder temperatures, below a gelation temperature, Tgel, the proteins assemble into a kinetically trapped gel state that arrests ATPS formation. The kinetics of ATPS formation near Tgel is associated with a remarkably fragile solid-like gel structure, which can form below either the metastable or the spinodal region of the phase diagram.

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