Influence of binary microgel phase behavior on the assembly of multi-functional raspberry-structured microgel heteroaggregates

Abstract

We investigate the influence of microgel composition on phase behavior of binary microgel dispersions using poly(N-isopropylacrylamide) microgels cross-linked with 5 mol-% and 1 mol-% N,N′-methylenebis(acrylamide), or poly(N-isopropylmethacrylamide) microgels cross-linked with 5 mol-% N,N′-methylenebis(acrylamide). We then explore the dispersion phase behavior in the context of microgel deposition at a planar interface. These results are then compared to the observed assembly of microgels at curved interfaces, in the form of raspberry-like patchy particles (RLPPs) consisting of a polystyrene core surrounded by a (two-component) microgel shell. Results suggest that microgel composition has a large influence on the ability of binary dispersions to coat planar and curved interfaces. In particular, we demonstrate that binary dispersions of microgels containing higher cross-linker content exhibit decreased packing densities that are very pronounced at a curved interface. To enhance packing density we also explore the use of a two-step coating process to fabricate RLPPs with enhanced control over topography. Development of these complex vehicles is potentially beneficial in the modulation of biological systems where spatial and temporal presentation of molecules can have a large influence on cellular behavior.

From binary AB to ternary ABC supraparticles

“…On the other hand, the ex situ approaches make use of the controlled assembly of inorganic and polymeric nanoparticles that are both preformed and it has been shown in the literature that raspberry-like supraparticles can be obtained from binary mixtures of oppositely charged colloids by using two different components. [22][23][24][25] Almost 40 years ago Vincent et al laid the ground for this field of adsorption of oppositely charged small particles onto larger particles by utilizing colloidal self-assembly of individual nanoparticles at different electrolyte concentrations via electrostatic interactions. 26,27 Ever since then electrostatic interactions between small and larger nanoparticles have been exploited to create binary supraparticles from inorganic and organic nanoparticles.…”

Porous Self-Assemblies Mediated by Dumbbell Particles as Cross-Linking Agents

“…Self-assembly of colloidal particles that are anisotropically decorated with patches is increasingly becoming a useful approach for manufacturing advanced materials with applications in several fields, − including photonics, − catalysis, − and tissue engineering. , The anisotropic placement of patches on the surfaces of particles provides selective and directional interactions that can be tuned, resulting in self-assembled materials with different morphological properties. − Conventionally, these patches were mainly composed of small biochemical entities, , including complementary DNA strands − and hydrophobic molecules, − which typically have a negligible volume when compared to the size of the colloidal particles.…”

Injectable microfluidic hydrogel microspheres based on chitosan and poly(ethylene glycol) diacrylate (PEGDA) as chondrocyte carriers

“…Furthermore, developing injectable hydrogel scaffolds that can mimic the microenvironment of cartilage for enhancing chondrocyte aggregation and proliferation remains challenging. [16][17][18][19] Contrastively, utilizing cell-laden micrometer-scale hydrogel microspheres as biobricks has been paid more and more attention, [20][21][22][23][24] which showed numerous attractive advantages compared with the conventional 3D bulk hydrogel scaffolds. In addition, such hydrogel microspheres as cell carriers were able to self-assemble into 3D scaffolds based on the bottom-to-up approach.…”