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Abstract Short oligomeric peptides typically do not exhibit the entanglements required for the formation of nanofibers via electrospinning. In this study, the synthesis of nanofibers composed of tyrosine‐based dipeptides via electrospinning, has been demonstrated. The morphology, mechanical stiffness, biocompatibility, and stability under physiological conditions of such biodegradable nanofibers were characterized. The electrospun peptide nanofibers have diameters less than 100 nm and high mechanical stiffness. Raman and infrared signatures of the peptide nanofibers indicate that the electrostatic forces and solvents used in the electrospinning process lead to secondary structures different from self‐assembled nanostructures composed of similar peptides. Crosslinking of the dipeptide nanofibers using 1,6‐diisohexanecyanate (HMDI) improved the physiological stability, and initial biocompatibility testing with human and rat neural cell lines indicate no cytotoxicity. Such electrospun peptides open up a realm of biomaterials design with specific biochemical compositions for potential biomedical applications such as tissue repair, drug delivery, and coatings for implants.
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Peptide-based assembled nanostructures that can direct cellular responses
Abstract Natural originated materials have been well-studied over the past several decades owing to their higher biocompatibility compared to the traditional polymers. Peptides, consisting of amino acids, are among the most popular programmable building blocks, which is becoming a growing interest in nanobiotechnology. Structures assembled using those biomimetic peptides allow the exploration of chemical sequences beyond those been routinely used in biology. In this review, we discussed the most recent experimental discoveries on the peptide-based assembled nanostructures and their potential application at the cellular level such as drug delivery. In particular, we explored the fundamental principles of peptide self-assembly and the most recent development in improving their interactions with biological systems. We believe that as the fundamental knowledge of the peptide assemblies evolves, the more sophisticated and versatile nanostructures can be built, with promising biomedical applications.
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- Award ID(s):
- 2023668
- PAR ID:
- 10432146
- Date Published:
- Journal Name:
- Biomedical Materials
- Volume:
- 17
- Issue:
- 6
- ISSN:
- 1748-6041
- Page Range / eLocation ID:
- 062002
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Abstract The conduction efficiency of ions in excitable tissues and of charged species in organic conjugated materials both benefit from having ordered domains and anisotropic pathways. In this study, a photocurrent‐generating cardiac biointerface is presented, particularly for investigating the sensitivity of cardiomyocytes to geometrically comply to biomacromolecular cues differentially assembled on a conductive nanogrooved substrate. Through a polymeric surface‐templated approach, photoconductive substrates with symmetric peptide‐quaterthiophene (4T)‐peptide units assembled as 1D nanostructures on nanoimprinted polyalkylthiophene (P3HT) surface are developed. The 4T‐based peptides studied here can form 1D nanostructures on prepatterned polyalkylthiophene substrates, as directed by hydrogen bonding, aromatic interactions between 4T and P3HT, and physical confinement on the nanogrooves. It is observed that smaller 4T‐peptide units that can achieve a higher degree of assembly order within the polymeric templates serve as a more efficient driver of cardiac cytoskeletal anisotropy than merely presenting aligned ‐RGD bioadhesive epitopes on a nanotopographic surface. These results unravel some insights on how cardiomyocytes perceive submicrometer dimensionality, local molecular order, and characteristics of surface cues in their immediate environment. Overall, the work offers a cardiac patterning platform that presents the possibility of a gene modification‐free cardiac photostimulation approach while controlling the conduction directionality of the biotic and abiotic components.more » « less
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Abstract Self‐assembled peptide materials have emerged as promising bioinspired tools for applications that include regenerative medicine, drug delivery, antimicrobial and vaccine development, optics, and catalysis. Peptide self‐assembly mediated by noncovalent hydrogen bonding, coulombic, hydrophobic, and aromatic interactions gives rise to a variety of supramolecular structures that reflect on the nature of the constituent peptides. The emergent properties of these supramolecular peptide materials often depend on the multivalent presentation of functional appendages on the self‐assembled scaffold. For example, the multivalent display of cell‐signaling motifs on self‐assembled peptide nanofibrils provides materials that are excellent extracellular matrix mimetics for tissue engineering applications. This review includes a discussion of chemical strategies that address the challenge of appending functional signal motifs in a multivalent display on self‐assembled peptide and protein materials. In addition, recent examples of supramolecular peptide materials that rely on the multivalent display of chemical signals for the desired applications are presented. Collectively, this discussion illustrates the potential of self‐assembled peptides as sustainable materials to address challenges in contemporary materials science and provides principles for the design of next‐generation agents for a variety of applications.more » « less
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1088/1748-605X/ac92b5
