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A microfluidic strategy has been used for the time- and labour-efficient evaluation of the relative efficiency and thermodynamic parameters of CO2 binding by three Lewis acid/base combinations, where efficiency is based on the amount of CO2 taken up per binding unit in solution. Neither tBu3P nor B(C6F5)3 were independently effective at CO2 capture, and the combination of the imidazolin-2-ylidenamino-substituted phosphine (NIiPr)3P and B(C6F5)3 was equally ineffective. Nonetheless, an archetypal frustrated Lewis pair (FLP) comprised of tBu3P and B(C6F5)3 was shown to bind CO2 more efficiently than either the FLP derived from tetramethylpiperidine (TMP) and B(C6F5)3 or the highly basic phosphine (NIiPr)3P. Moreover, the proposed microfluidic platform was used to elucidate the thermodynamic parameters for these reactions.

A microfluidic strategy has been used for the time- and labour-efficient evaluation of the relative efficiency and thermodynamic parameters of CO2 binding by three Lewis acid/base combinations, where efficiency is based on the amount of CO2 taken up per binding unit in solution. Neither tBu3P nor B(C6F5)3 were independently effective at CO2 capture, and the combination of the imidazolin-2-ylidenamino-substituted phosphine (NIiPr)3P and B(C6F5)3 was equally ineffective. Nonetheless, an archetypal frustrated Lewis pair (FLP) comprised of tBu3P and B(C6F5)3 was shown to bind CO2 more efficiently than either the FLP derived from tetramethylpiperidine (TMP) and B(C6F5)3 or the highly basic phosphine (NIiPr)3P. Moreover, the proposed microfluidic platform was used to elucidate the thermodynamic parameters for these reactions.

Patterning of colloidal particles with chemically or topographically distinct surface domains (patches) has attracted intense research interest. Surface-patterned particles act as colloidal analogues of atoms and molecules, serve as model systems in studies of phase transitions in liquid systems, behave as 'colloidal surfactants' and function as templates for the synthesis of hybrid particles. The generation of micrometre- and submicrometre-sized patchy colloids is now efficient, but surface patterning of inorganic colloidal nanoparticles with dimensions of the order of tens of nanometres is uncommon. Such nanoparticles exhibit size- and shape-dependent optical, electronic and magnetic properties, and their assemblies show new collective properties. At present, nanoparticle patterning is limited to the generation of two-patch nanoparticles, and nanoparticles with surface ripples or a 'raspberry' surface morphology. Here we demonstrate nanoparticle surface patterning, which utilizes thermodynamically driven segregation of polymer ligands from a uniform polymer brush into surface-pinned micelles following a change in solvent quality. Patch formation is reversible but can be permanently preserved using a photocrosslinking step. The methodology offers the ability to control the dimensions of patches, their spatial distribution and the number of patches per nanoparticle, in agreement with a theoretical model. The versatility of the strategy is demonstrated by patterning nanoparticles with different dimensions, shapes and compositions, tethered with various types of polymers and subjected to different external stimuli. These patchy nanocolloids have potential applications in fundamental research, the self-assembly of nanomaterials, diagnostics, sensing and colloidal stabilization.

Author(s): Min Liu [1]; Yuanjie Pang [2]; Bo Zhang [1, 3]; Phil De Luna [4]; Oleksandr Voznyy [1]; Jixian Xu [1]; Xueli Zheng [1, 5]; Cao Thang Dinh [1]; Fengjia [...]

The article focuses on multicellular cancer spheroids in vitro model that replicates many features of solid tumors in vivo. It mentions that biomimetic hydrogel scaffolds for MCS growth recapitulate the behavior of natural extracellular matrix, essential for regulating cancer cell behavior. It further review the use of different types of hydrogels for MCS growth.

An important goal of the modern soft matter science is to discover new self-assembly modalities to precisely control the placement of small particles in space. Spatial inhomogeneity of liquid crystals offers the capability to organize colloids in certain regions such as the cores of the topological defects. Here we report two self-assembly modes of nanoparticles in linear defects-disclinations in a lyotropic colloidal cholesteric liquid crystal: a continuous helicoidal thread and a periodic array of discrete beads. The beads form one-dimensional arrays with a periodicity that matches half a pitch of the cholesteric phase. The periodic assembly is governed by the anisotropic surface tension and elasticity at the interface of beads with the liquid crystal. This mode of self-assembly of nanoparticles in disclinations expands our ability to use topological defects in liquid crystals as templates for the organization of nanocolloids. [ABSTRACT FROM AUTHOR]

Microscale technologies offer the capability to generate in vitro artificial cellular microenvironments that recapitulate the spatial, biochemical, and biophysical characteristics of the native extracellular matrices and enable systematic, quantitative, and high-throughput studies of cell fate in their respective environments. We developed a microfluidic platform for the generation of two-dimensional arrays of micrometer-size cell-laden hydrogel modules (HMs) for cell encapsulation and culture. Fibroblast cells (NIH 3T3) and non-adherent T cells (EL4) encapsulated in HMs showed high viability and proliferation. The platform was used for real-time studies of the effect of spatial constraints and structural and mechanical properties of HMs on cell growth, both on the level of individual cells. Due to the large number of cellladen HMs and stochastic cell distribution, cell studies were conducted in a time- and labor efficient manner. The platform has a broad range of applications in the exploration of the role of chemical and biophysical cues on individual cells, studies of in vitro cell migration, and the examination of cell-extracellular matrix and cell-cell interactions. [ABSTRACT FROM AUTHOR]

The article discusess a study conducted for achieving precise organization of nanoparticles (NPs) in three-dimensional space. It examines morphogenesis of nanoparticle assemblies and a cholesteric liquid crystalline host formed by cellulose nanocrystals for experiencing marked changes in shape and structure as a function of concentration. It mentions increase in NP loading triggers reversible droplet transformation to gain a core-shell morphology with an isotropic core.