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We report a simple method for producing polymeric microparticles with controlled three-dimensional (3D) shapes from two-dimensional (2D) micromolds via mold geometry-mediated tunable mold swelling and capillarity. Specifically, the photocurable solution confined in the mold with diverse geometries is spatially deformed by the addition of the wetting fluid, which triggers the mold swelling and capillarity; this allows the production of highly uniform microparticles with complex shape via photopolymerization. The results show that the swelling-induced mold deflection is varied depending on the mold geometry with different side lengths, allowing a tunable deformation of the photocurable solution and forming non-spherical particles with a convex top. The capillarity of the wetting fluid is also determined by the mold geometry with different corner angles, leading to the directional movement of the photocurable solution via Laplace pressure-driven flow and facilitating the production of spherical particles with or without shape imprinting. Furthermore, we demonstrate a capability to further enhance the mold swelling by varying mold composition, expanding their controllability in 3D shape, and enabling simultaneous production of spherical and non-spherical particles using a single mold., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2021 Elsevier Inc. All rights reserved.)

A unique, tailor-made, zwitterionic, dual thermoresponsive and fluorescent microgel probe was synthesized via Reversible Addition Fragmentation chain-Transfer (RAFT) polymerization. Microgels were prepared via oil in water (o/w) emulsion polymerization where poly(carboxybetaine) (PCB) acted as a macro-RAFT reagent as well as an emulsifier. The presence of poly(N-vinylcaprolactam) (PNVCL) in the microgel system imparts the thermoresponsiveness to the system and the presence of a rhodamine derivative as fluorophore makes it responsive to pH change of the system by showing a fluorescence emission at 580 nm (reddish orange color). The dual thermoresponsiveness [i.e. the presence of upper critical solution temperature (UCST @ 12 °C) as well as lower critical solution temperature (LCST @ 33 °C)] of the microgels was studied via UV-visible spectroscopy (UV-vis) and temperature responsive dynamic light scattering (DLS) analyses. Presence of the PCB in the corona-crosslinked microgel, played a vital role in the formation of self-assembled structure as well as in protein immobilization (antifouling activity). Antifouling property was studied using UV-vis spectroscopy where bovine serum albumin (BSA) was taken as a model protein. The presence of the pH-responsive fluorescence, thermoresponsiveness as well as antifouling properties makes this zwitterionic microgel system a potential a potential candidate for medical diagnostics and for drug delivery vehicles., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier Inc. All rights reserved.)

Hypothesis: Quantitative characterization of surface wettability through contact angle (CA) measurement using the sessile droplet (SD) or captive bubble (CB) methods is often limited by the intrinsic wetting properties of the substrate. Situations may arise when an extreme surface wettability may preclude using one of the two methods for predicting the behaviors of droplets or bubbles on the surface. This warrants a relationship between the dynamic CAs measured via the SD and CB methods. While the two dynamic CAs (e.g., the advancing CA of SD and receding CA of CB) add up to 180° on a smooth surface, the simple geometric supplementary principle may not apply for rough surfaces., Experiments: We perform a systematic wettability characterization of solid substrates with varying degrees of roughness using the sessile-droplet and captive-bubble methods, and interpret the experimental observations using a theoretical model., Findings: The dynamic contact angles measured by the sessile-droplet and captive-bubble methods deviate from the supplementary principle as the surface roughness is increased. We present a theoretical explanation for this disparity and predict the values of the contact angles using prevalent thermodynamic models of wetting and contact-angle hysteresis on rough substrates. The theoretical prediction is in good agreement with the experimental observations., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier Inc. All rights reserved.)

N,N,N',N'-tetraoctyl diglycolamide abbreviated as TODGA, is one of the most promising extractant for actinide partitioning from high level nuclear waste. It forms reverse micelles in non polar solvents on equilibration with aqueous HNO(3) solutions. This reverse micellar system undergoes phase separation into dilute and concentrated reverse micellar solutions at high aqueous acid concentration. Small angle neutron scattering (SANS) studies reported in the literature explained this phenomenon based on gas-liquid type phase transition in the framework of Baxter adhesive hard sphere theory in the presence of a strong inter-micellar attractive interaction. The present investigation attempts to throw further light on this system by carrying out systematic dynamic light scattering (DLS) and viscometry studies, and their modeling on the TODGA reverse micellar solutions in the dodecane medium. The variation of the diffusion coefficient with the micellar volume fraction observed from the DLS studies is suggestive of the presence of an attractive interaction between the TODGA reverse micelles, which weakens at the high micellar volume fraction due to the increased dominance of the excluded volume effect. It is suggested that this weakened interaction is responsible for the absence of phase separation in this system at high TODGA concentration. The results thus highlight the importance of the presence of an attractive interaction between the TODGA micelles in determining the observed phase separation in the TODGA reverse micellar systems. The modeling of the DLS and viscosity data, however, suggest that the characteristic stickiness parameter of this system could be smaller than the critical value required for inducing a gas-liquid type phase transition., (Copyright © 2010 Elsevier Inc. All rights reserved.)