Carbon nanomaterials include diverse structures and morphologies, such as fullerenes, nano-onions, nanodots, nanodiamonds, nanohorns, nanotubes, and graphene-based materials. They have attracted great interest in medicine for their high innovative potential, owing to their unique electronic and mechanical properties. In this review, we describe the most recent advancements in their inclusion in hydrogels to yield smart systems that can respond to a variety of stimuli. In particular, we focus on graphene and carbon nanotubes, for applications that span from sensing and wearable electronics to drug delivery and tissue engineering.
Ceria (CeO2) nanostructures are well-known in catalysis for energy and environmental preservation and remediation. Recently, they have also been gaining momentum for biological applications in virtue of their unique redox properties that make them antioxidant or pro-oxidant, depending on the experimental conditions and ceria nanomorphology. In particular, interest has grown in the use of biotemplates to exert control over ceria morphology and reactivity. However, only a handful of reports exist on the use of specific biomolecules to template ceria nucleation and growth into defined nanostructures. This review focusses on the latest advancements in the area of biomolecular templates for ceria nanostructures and existing opportunities for their (bio)applications.
Carbon nanomaterials (CNMs) and enzymes differ significantly in terms of their physico-chemical properties—their handling and characterization require very different specialized skills. Therefore, their combination is not trivial. Numerous studies exist at the interface between these two components—especially in the area of sensing—but also involving biofuel cells, biocatalysis, and even biomedical applications including innovative therapeutic approaches and theranostics. Finally, enzymes that are capable of biodegrading CNMs have been identified, and they may play an important role in controlling the environmental fate of these structures after their use. CNMs’ widespread use has created more and more opportunities for their entry into the environment, and thus it becomes increasingly important to understand how to biodegrade them. In this concise review, we will cover the progress made in the last five years on this exciting topic, focusing on the applications, and concluding with future perspectives on research combining carbon nanomaterials and enzymes.
Self-assembling peptides and carbon nanomaterials have attracted great interest for their respective potential to bring innovation in the biomedical field. Combination of these two types of building blocks is not trivial in light of their very different physico-chemical properties, yet great progress has been made over the years at the interface between these two research areas. This concise review will analyze the latest developments at the forefront of research that combines self-assembling peptides with carbon nanostructures for biological use. Applications span from tissue regeneration, to biosensing and imaging, and bioelectronics.
13 March 2023 in Angewandte Chemie International Edition
A double‐walled tetrahedral metal‐organic cage assembled in solution from silver(I), 2‐formyl‐1,8‐naphthyridine, halide, and a threefold‐symmetric triamine. The AgI4X clusters at its vertices each bring together six naphthyridine‐imine moieties, leading to a structure in which eight tritopic ligands bridge four clusters in an (AgI4X)4L8 arrangement. Four ligands form an inner set of tetrahedron walls that are surrounded by the outer four. The cage has significant interior volume, and was observed to bind anionic guests. The structure also possesses external binding clefts, located at the edges of the cage, which bound small aromatic guests. Halide ions bound to the silver clusters were observed to exchange in a well‐defined hierarchy, allowing modulation of the cavity volume. The principles uncovered here may allow for increasingly more sophisticated cages with silver‐cluster vertex architectures, with post‐assembly tuning of the interior cavity volume enabling targeted binding behavior.
Dipeptides are convenient building blocks for supramolecular gel biomaterials that can be produced on a large scale at low cost and do not persist in the environment. In the case of unprotected sequences, hydrophobicity is a key requirement to enable gelation, with Phe–Phe standing out for its self-assembling ability. Conversely, more hydrophilic sequences such as homochiral dipeptides Phe–Val and Val–Phe neither fibrillate nor gel aqueous buffers and their crystal structures reveal amphipathic layers. In this work, we test emerging rules for the design of self-assembling dipeptides using heterochiral Phe–Val and Val–Phe. Each dipeptide is characterized by 1H- and 13C-NMR, LC-MS, circular dichroism, infrared and Raman spectroscopies, rheology, electron microscopy, and single-crystal X-ray diffraction. In particular, D-Phe–L-Val is the first heterochiral dipeptide to self-assemble into supramolecular water-channels whose cavity is defined by four peptide molecules arranged head-to-tail. This minimalistic sequence is devoid of amyloid character as probed by thioflavin T fluorescence and it displays excellent biocompatibility in vitro. The dataset provided, through comparison with the literature, significantly advances the definition of molecular design rules for minimalistic unprotected dipeptides that self-assemble into water-channels and biocompatible gels, to assist with the future development of supramolecular biomaterials with fine control over nanomorphological features for a variety of applications.