Dynamic and flexible nucleic acid models can provide current and future scientists with physical intuition for the structure of DNA and the ways that DNA and its synthetic mimics can be used to build self-assembling structures and advanced nanomachines. As more research labs and classrooms dive into the field of structural nucleic acid nanotechnology, students and researchers need access to interactive, dynamic, handheld models. Here, we present a 3D-printable kit for the construction of DNA and peptide nucleic acid (PNA). We have engineered a previous modular DNA kit to reduce costs while improving ease of assembly, flexibility, and robustness. We have also expanded the scope of available snap-together models by creating the first 3D-printable models of γPNA, an emerging material for nuclease- and protease-resistance nanotechnology. Building on previous research, representative nucleic acid duplexes were split into logical monomer segments, and atomic coordinates were used to create solid models for 3D printing. We used a human factors approach to customize 3 types of articulated snap-together connectors that allow for physically relevant motion characteristic of each interface in the model. Modules are easy to connect and separate manually but stay together when the model is manipulated. To greatly reduce cost, we bundled these segments for printing, and we created a miniaturized version that uses less than half the printing material to build. Our novel 3D-printed articulated snap-together models capture the flexibility and robustness of DNA and γPNA nanostructures. Resulting handheld helical models replicate the geometries in published structures and can now flex to form crossovers and allow biologically relevant zipping and unzipping to allow complex demonstrations of nanomachines undergoing strand displacement reactions. Finally, the same tools used to create these models can be readily applied to other types of backbones and nucleobases for endless research and education possibilities.
3D printing has become one of the primary fabrication strategies used in biomedical research. Recent efforts have focused on the 3D printing of hydrogels to create structures that better replicate the mechanical properties of biological tissues. These pose a unique challenge, as soft materials are difficult to pattern in three dimensions with high fidelity. Currently, a small number of biologically derived polymers that form hydrogels are frequently reused for 3D printing applications. Thus, there exists a need for novel hydrogels with desirable biological properties that can be used as 3D printable inks. In this work, the printability of multidomain peptides (MDPs), a class of self‐assembling peptides that form a nanofibrous hydrogel at low concentrations, is established. MDPs with different charge functionalities are optimized as distinct inks and are used to create complex 3D structures, including multi‐MDP prints. Additionally, printed MDP constructs are used to demonstrate charge‐dependent differences in cellular behavior in vitro. This work presents the first time that self‐assembling peptides have been used to print layered structures with overhangs and internal porosity. Overall, MDPs are a promising new class of 3D printable inks that are uniquely peptide‐based and rely solely on supramolecular mechanisms for assembly.
more » « less- NSF-PAR ID:
- 10393045
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Advanced Materials
- Volume:
- 35
- Issue:
- 11
- ISSN:
- 0935-9648
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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