Fullerene-Based Mimics of Biocatalysts Show Remarkable Activity and Modularity

Iridium nanoparticles supported on polyaniline nanotubes for peroxidase mimicking towards total antioxidant capacity assay of fruits and vegetables

In this study, a straightforward approach is presented for the first time to anchor Ir nanoparticles on the surface of uniform polyaniline (PANi) nanotubes (NTs), which can be used as an efficient peroxidase (POD)-like catalyst. The morphology and chemical structure of the PANi-Ir nanocomposite are characterized by scanning electron microscopy (SEM), high-resolution transmission electron microscopy (HRTEM), X-ray diffractometer (XRD), Raman and X-ray photoelectron spectroscopy (XPS) measurements. Owing to the strong interaction between Ir nanoparticles and PANi, a remarkable catalytic enhancement is achieved compared to the bare Ir black catalyst and individual PANi NTs, dominating withan electron transfer mechanism. Furthermore, an efficient colorimetric sensor for ascorbic acid (AA) is developed with a low detection limit of 1.0 μM (S/N = 3), and a total antioxidant capacity (TAC) sensing platform is also constructed for the rigorous detection and analysis of fruits and vegetables.

Rational design of an acceptor-chromophore-relay-catalyst tetrad assembly for water oxidation

We report the step-by-step synthesis of a precious metal-free acceptor-chromophore-relay-catalyst tetrad assembly that exhibits a turnover frequency (TOF) of 7.5 × 10-3 s-1 under neutral conditions. Transient absorption spectroscopic studies indicate that upon fullerenol incorporation into the investigated complexes, charge separation efficiency increases considerably.

Bioinspired Multi-Layer Biopolymer-Based Dental Implant Coating for Enhanced Osseointegration

The major drawbacks of metal-based implants are weak osseointegration and post-operational infections. These limitations restrict the long-term use of implants that may cause severe tissue damage and replacement of the implant. Recent strategies to enhance the osseointegration process require an elaborate fabrication process and suffer from post-operative complications. To address the current challenges taking inspiration from the extracellular matrix (ECM), the current study is designed to establish enhanced osseointegration with lowered risk of infection. Natural biopolymer pectin, peptide amphiphiles, and enzyme-mimicking fullerene moieties are governed to present an ECM-like environment around the implant surfaces. This multifunctional approach promotes osseointegration via inducing biomineralization and osteoblast differentiation. Application of the biopolymer-based composite to the metal surfaces significantly enhances cellular attachment, supports the mineral deposition, and upregulates osteoblast-specific gene expression. In addition to the osteoinductive properties of the constructed layers, the inherent antimicrobial properties of multilayer coating are also used to prevent infection possibility. The reported biopolymer-artificial enzyme composite demonstrates antimicrobial activity against Escherichia coli and Bacillus subtilis as a multifunctional surface coating.

Unusual Mathematical Approaches Untangle Nervous Dynamics

The massive amount of available neurodata suggests the existence of a mathematical backbone underlying neuronal oscillatory activities. For example, geometric constraints are powerful enough to define cellular distribution and drive the embryonal development of the central nervous system. We aim to elucidate whether underrated notions from geometry, topology, group theory and category theory can assess neuronal issues and provide experimentally testable hypotheses. The Monge’s theorem might contribute to our visual ability of depth perception and the brain connectome can be tackled in terms of tunnelling nanotubes. The multisynaptic ascending fibers connecting the peripheral receptors to the neocortical areas can be assessed in terms of knot theory/braid groups. Presheaves from category theory permit the tackling of nervous phase spaces in terms of the theory of infinity categories, highlighting an approach based on equivalence rather than equality. Further, the physical concepts of soft-matter polymers and nematic colloids might shed new light on neurulation in mammalian embryos. Hidden, unexpected multidisciplinary relationships can be found when mathematics copes with neural phenomena, leading to novel answers for everlasting neuroscientific questions. For instance, our framework leads to the conjecture that the development of the nervous system might be correlated with the occurrence of local thermal changes in embryo–fetal tissues.

Nanoarchitectonics of Fullerene Based Enzyme Mimics for Osteogenic Induction of Stem Cells

Enzyme mimicry is a topic of considerable interest in the development of multifunctional biomimetic materials. Mimicking enzyme activity is a major challenge in biomaterials research, and artificial analogs that simultaneously recapitulate the catalytic and metabolic activity of native enzymes are considered to be the ultimate goal of this field. This consensus may be challenged by self-assembling multifunctional nanostructures to develop close-to-fidelity enzyme mimics. Here, we present the ability of fullerene nanostructures decorated with active units to form enzyme-like materials that can mimic phosphatases in a metal-free manner. These nanostructures self-assemble into nanoclusters forming multiple random active sites that can cleave both phosphomonoesters and phosphodiesters while being more specific for the phosphomonoesters. Moreover, they are reusable and show an increase in catalytic activity over multiple cycles similar to their natural counterparts. In addition to having enzyme-like catalytic properties, these nanocatalysts imitate the biological functions of their natural analogs by inducing biomineralization and osteoinduction in preosteoblast and mesenchymal stem cells in vitro studies. This article is protected by copyright. All rights reserved.

Carbon Nanomaterials (CNMs) and Enzymes: From Nanozymes to CNM-Enzyme Conjugates and Biodegradation

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.