arXiv subjects

Senthilkumar Duraivel

Publications and source records attributed to Senthilkumar Duraivel.

4 recordsLinked to original sources

arXiv2026

Dispersion Polymerization in an Elastomeric Solvent

Polymerization-induced phase separation (PIPS) provides a powerful route to generate structured polymeric materials by coupling chemical conversion with thermodynamic demixing. PIPS in liquid-state systems underlies dispersion polymerization, serving as a cornerstone technique for microparticle production, yet is constrained by solvent compatibility and limited range of morphologies. Here, we establish an elastically mediated PIPS regime that bridges these two limits by conducting controlled polymerization within a deformable elastomeric network. This approach, termed Dispersion Polymerization in an Elastomeric Solvent (DiPolES), serves as a solid-state analogue of dispersion polymerization in which an elastomeric network simultaneously serves as solvent and physical stabilizer. Using photoiniferter-mediated polymerization of methyl methacrylate (MMA) within poly(dimethyl siloxane) (PDMS) elastomeric solvent, DiPolES enables robust fabrication of elastomeric composites containing uniform PMMA microparticles with tunable size (0.85 to 3 {\mu}m) and shape (spheroidal and ellipsoidal). The strategy is generalizable beyond the PDMS/MMA system and is applicable to diverse monomers, such as acrylonitrile and 2-vinyl pyridine, which can be extracted from the elastomeric solvent, enabling high-yield production of microparticles. Real-time imaging and compositional analysis reveal that particle formation proceeds through rapid nucleation at low monomer conversion, followed by growth accompanied by cavitation of the surrounding network. Monomer loading governs the particle size, while solvent elasticity modulates the transition from isolated uniform spheroids to heterogeneous clusters. Interestingly, applying uniaxial strain during DiPolES enables production of ellipsoidal particles without any post-processing.

cond-mat.soft↗

arXiv2024

A Functional Human Liver Tissue Model: 3D Bioprinted Co-culture Discoids

To reduce costs and delays related to developing new and effective drugs, there is a critical need for improved human liver tissue models. Here we describe an approach for 3D bioprinting functional human liver tissue models, in which we fabricate disc-shaped structures (discoids) 200 μm in thickness and 1-3 mm in diameter, embedded in a highly permeable support medium made from packed microgels. We demonstrate that the method is precise, accurate, and scalable; up to 100 tissues per hour can be manufactured with a variability and error in diameter of about 4%. Histologic and immunohistochemical evaluation of printed discs reveal self-organization, cell cohesion, and key liver marker expression. During the course of 3-4 weeks in culture, the tissues stably synthesize albumin and urea at high levels, outperforming spheroid tissue models. We find the tissues express more than 100 genes associated with molecular absorption, distribution, metabolism, and excretion (ADME) at levels within the range of human liver. The liver tissue models exhibit enzymatic formation of metabolites after exposure to multiple test compounds. Together, these results demonstrate the promise of 3D printed discoids for pharmacological and toxicological applications.

cond-mat.soft↗

arXiv2024

Unravelling the multiscale surface mechanics of soft solids

Soft solids and their surface deformations control the response of many natural and artificial systems. Yet, their underlying properties are vigorously debated, particularly for polymer networks. While molecular-scale theories predict no interfacial changes with macroscopic deformation, multiple experiments suggest otherwise. To settle this issue, we measure displacement fields near the interface of a silicone gel, in the limit of small deformations. We discover an unexpected multiscale response. The shear modulus decreases smoothly by half with 20 microns of the interface. At the same time we observe a surface excess elasticity, that depends on history and outer medium composition. These results reveal the fundamentally multiscale nature of polymeric surfaces, and call for further experimental and theoretical investigations into the basic understanding of soft solid interfaces

cond-mat.soft↗

arXiv2022

Cellular Micromasonry: Biofabrication with Single Cell Precision

In many tissues, cell type varies over single-cell length-scales, creating detailed spatial heterogeneities fundamental to physiological function. To gain understanding of this relationship between tissue function and detailed structure, and to one day engineer structurally and physiologically accurate tissues, we need the ability to assemble 3D cellular structures having the level of detail found in living tissue. Here we introduce a method of 3D cell assembly that has a level of precision finer than the single-cell scale. With this method we create numerous structures having well-defined spatial patterns, demonstrating that cell type can be varied over the scale of individual cells and showing function after their assembly. This technique provides innumerable opportunities to study cellular behavior in defined contexts including complex interactions operating during embryogenesis.

cond-mat.soft↗