Conductive hydrogels are attractive to mimic electrophysiological environments of biological tissues and toward therapeutic applications. Injectable and conductive hydrogels are of particular interest for applications in 3D printing or for direct injection into tissues; however, current approaches to add conductivity to hydrogels are insufficient, leading to poor gelation, brittle properties, or insufficient conductivity. Here, an approach is developed using the jamming of microgels to form injectable granular hydrogels, where i) hydrogel microparticles (i.e., microgels) are formed with water‐in‐oil emulsions on microfluidics, ii) microgels are modified via an in situ metal reduction process, and iii) the microgels are jammed into a solid, permitting easy extrusion from a syringe. Due to the presence of metal nanoparticles at the jammed interface with high surface area in this unique design, the granular hydrogels have greater conductivity than non‐particle (i.e., bulk) hydrogels treated similarly or granular hydrogels either without metal nanoparticles or containing encapsulated nanoparticles. The conductivity of the granular hydrogels is easily modified through mixing conductive and non‐conductive microgels during fabrication and they can be applied to the 3D printing of lattices and to bridge muscle defects. The versatility of this conductive granular hydrogel will permit numerous applications where conductive materials are needed.
Herein, we describe a 3D printable hydrogel that is capable of removing toxic metal pollutants from aqueous solution. To achieve this, shear‐thinning hydrogels were prepared by blending chitosan with diacrylated Pluronic F‐127 which allows for UV curing after printing. Several hydrogel compositions were tested for their ability to absorb common metal pollutants such as lead, copper, cadmium and mercury, as well as for their printability. These hydrogels displayed excellent metal adsorption with some examples capable of up to 95% metal removal within 30 min. We show that 3D printed hydrogel structures that would be difficult to fabricate by conventional manufacturing methods can adsorb metal ions significantly faster than solid objects, owing to their higher accessible surface areas. © 2019 Society of Chemical Industry
more » « less- Award ID(s):
- 1654405
- NSF-PAR ID:
- 10461694
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Polymer International
- Volume:
- 68
- Issue:
- 5
- ISSN:
- 0959-8103
- Page Range / eLocation ID:
- p. 964-971
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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