Photoencapsulation of chondrocytes in poly(ethylene oxide)-based semi-interpenetrating networks

Abstract

A photopolymerizing hydrogel system provides an efficient method to encapsulate cells. The present work describes the in vitro analysis of bovine and ovine chondrocytes encapsulated in a poly(ethylene oxide)-dimethacrylate and poly(ethylene glycol) semi-interpenetrating network using a photopolymerization process. One day after encapsulation, (3-[4,5-dimethylthiazol-2-y1]-2, 5-diphenyl-2H-tetrazolium bromide) (MTT) and light microscopy showed chondrocyte survival and a dispersed cell population composed of ovoid and elongated cells. Biochemical analysis demonstrated proteoglycan and collagen contents that increased over 2 weeks of static incubation. Cell content of the gels initially decreased and stabilized. Biomechanical analysis demonstrated the presence of a functional extracellular matrix with equilibrium moduli, dynamic stiffness, and streaming potentials that increased with time. These findings suggest the feasibility of photoencapsulation for tissue engineering and drug delivery purposes.

Two‐Photon Polymerization of Biocompatible Photopolymers for Microstructured 3D Biointerfaces

“…The degradation of PEGDA was not determined, but literature values indicate a slow degradation rate. [90] Scaffold Microfabrication Using 2PP…”

“…PEGDA is widely used in biomaterials and serves as a standard because of its good availability and biological inertness. [90] Although the cubic lattice is suitable for producing large volume scaffolds in a relatively short processing time, it is not optimal from the secundam-naturam paradigm: straight edges, acute angles, sharp turns and inhomogeneous curvature distribution along the scaffold surface are contra-naturam and should be prevented in biomorphic cell supports. A biomorphic geometry that mimics the secundam-naturam substrate and that is continuous through all space is the Schwarz primitive (P) minimal surface.…”

Organic Nanoparticles: Adapting Emerging Techniques from the Electronics Industry for the Generation of Shape‐Specific, Functionalized Carriers for Applications in Nanomedicine

“…This was accomplished by pooling a solution of PEG-diacrylate:2,2-dimethoxy-2-phenyl-acetophenone (99.7:0.3, w/w) on the rubber casting of the TiN-modified silicon-patterned substrate. The replicated structures composed were shown to be biocompatible and non-adhesive to protein and cells [65,66]. Moreover, by slightly altering the method these authors showed that they could fabricate a high aspect ratio (b 5) microarray of microcups composed of the same biocompatible material [67].…”

Single-cell-bioreactors as end of miniaturization approaches in biotechnology: progresses with characterised bioreactors and a glance into the future

“…More sophisticated methods incorporate self-degradation of the matrices for later retransplantation of the in vitro expanded cells based upon a polyglycolic acid non-woven mesh with fibrin gel matrix assistance [1]. Photochemical matrix formation approaches have also been assessed for purposes of chondrocyte immobilisation, although significant cell losses have been observed using these techniques [17].…”