The creation of carbon materials with controlled micro-architecture and 3D morphology from sustainable and biodegradable natural sources, especially at large scales, is a significant trend in modern materials science. Spongin, a renewable, fibrous biomaterial originating from industrially cultivated marine sponges, is already confirmed as a successful candidate for carbonization up to 1200 degrees C. This study shows for the first time that centimeter-sized 3D micro-fibrous spongin scaffolds can be carbonized at temperatures up to 2200 degrees C without loss of structural integrity or sponge-like form. Other biomaterials, even those initially having a 3D structural organization, crumble into powder when carbonized at such temperatures. The results of analytical studies obtained using XPS, Raman, NEXAFS, XRD, 13C solid state NMR spectroscopy and HRTEM clearly confirm the formation of turbostratic layered graphite with a surface containing diverse carbon nanophases including graphene, C60 nanocrystallites, and unique rhombohedral graphite with monoclinic C2/m space group symmetry. Examples of potential applications of the prepared graphite constructs are described, along with a discussion of the possibility of high-temperature production of exceptionally stable 3D carbon materials based on spongin.

This experimental review discusses evolutionarily approved, naturally pre-designed skeletal architectures of marine keratosan sponges in the form of 3D scaffolds, which have garnered increasing interest in the fields of structural and functional biomimetics as well as in tissue engineering. It has been demonstrated that these renewable, ready-to-use natural scaffolds can undergo further modifications through specialized treatments such as metallization and carbonization, enabling the creation of functional biomaterials while maintaining the species-specific hierarchical 3D structure. The study presented remarkable findings, including the demonstration of the unique shape-memory behavior of these scaffolds even after two months of exposure to high mechanical pressure at temperatures exceeding 100 °C. Additionally, the cytocompatibility and biological performance of natural and carbonized (1200 °C) spongin scaffolds, derived from selected bath sponges, were comparatively investigated with respect to growth and proliferation of human MG-63 osteoblastic cells. Understanding whether carbonization universally enhances osteogenic capabilities or selectively amplifies the inherent architectural advantages remains to be critical for the rational design of sponge-derived scaffolds in bone and structural tissue engineering applications.

The structural biocomposite spongin, which forms three-dimensional (3D) microporous skeletons in keratosan demosponges, known as the first multicellular organisms, belongs to sustainable biological materials. This study reports the first chromium tanning of spongin scaffolds isolated from two species of industrially used commercial sponges (Hippospongia communis and Spongia tampa) under extreme biomimetic conditions. Carbonization of the studied spongin samples followed by chromium plating led to the formation of complex multiphase structures never reported before. We use digital, and scanning electron microscopy, as well as XRD, FT-IR, XPS, thermogravimetric analysis and HR-TEM, for identification and characterization of the created 3D spongin-chromium composites. A mechanism for the interaction of chromium with the functional groups of spongin has also been proposed. Our data provide insights into the highly specific chemical and structural arrangements resulting from the Cr-tanning of diverse forms of spongin-based composite materials with perspectives of their practical applications including the hydrogen evolution reaction.

Extreme biomimetics represents a novel multidisciplinary direction within classical biomimetics and bioinspired materials science that draws inspiration from extremophiles and extreme natural habitats to create unusual approaches for the design of next-generation materials, including composites never reported or predicted before. This review is divided into several sections covering achievements and fundamental challenges in the following fields: sources of inspiration—organisms and locations; biological materials for extreme biomimetics based on examples of biosilica, cellulose, chitin, and structural proteins (collagen, byssus, silk, keratin). Additionally, conchixes of molluscan shell origin, fish scales, and spongin as a skeletal biocomposite of industrial sponge origin are represented and discussed from the viewpoint of extreme biomimetics. Finally, scientifically based but daring experimental decisions in modern extreme biomimetics, taking the examples of extreme carbonization of naturally pre-structured biomaterials, galvanobiomimetics, in-flame biomimetics, pyro-biomimetics, and ultra-high pressure mimetics are represented for the first time as current trends with challenging goals.

Spongin is a fundamental biopolymer that has played a crucial role in the skeletogenesis of keratosan sponges for over 800 million years. This biomaterial had so far remained chemically unidentified and believed to be an enigmatic type of halogenated collagen-keratin-based bioelastomer. Here we show collagen I and III as the main structural components of spongin. Proteomics, 13C solid state NMR and Raman spectroscopy confirm the identity of collagenous domains in spongin with collagen from mammals. Using an HPLC-MS analysis, we found halogenated di- and tri-tyrosines as crosslinking agents in spongin. Using molecular dynamics modeling, we solvated the crystal structures of collagen mimetic peptides for type I and type III collagens in four different systems, including selected brominated crosslinks. The results underscore the complex interplay between the collagen structures and crosslinks, raising intriguing questions about the molecular mechanisms underlying collagen chemistry within spongin as an ancient biocomposite.

This study presents a novel approach to fabricating magnetic sponge-like composites by melting various types of steel onto three-dimensional (3D) carbonized spongin scaffolds under extreme biomimetic conditions. Spongin, a renewable marine biopolymer with high thermal stability, was carbonized at 1200 °C to form a turbostratic graphite matrix capable of withstanding the high-temperature steel melting process (1450-1600 °C). The interaction between molten steel vapors and the carbonized scaffolds resulted in the formation of nanostructured iron oxide (primarily hematite) coatings, which impart magnetic properties to the resulting composites. Detailed characterization using SEM-EDX, HRTEM, FT-IR, and XRD confirmed the homogeneous distribution of iron oxides on and within the carbonized fibrous matrix. Electrochemical measurements further demonstrated the electrocatalytic potential of the composite, particularly the sample modified with stainless steel 316L-for the hydrogen evolution reaction (HER), offering promising perspectives for green hydrogen production. This work highlights the potential of extreme biomimetics to create functional, scalable, and sustainable materials for applications in catalysis, environmental remediation, and energy technologies.

The location of sponges (Porifera) at the base of the tree of origin of all multicellular organisms on our planet determines constant scientific interest in their study as model organisms. Sponge skeletons are biocomposite-containing 3D structures formed by minerals (silica, calcium carbonates) and organic phases with a clearly defined nanostructural organization. Nanofibrillar fundamental biopolymers such as chitin, spongin, collagens and actin take part in the formation of the unique bioarchitecture of poriferan skeletons. In this chapter, we discuss the current state of the work related to sponges' bioinspired materials science and biomimetics, taking inspiration from structural biology and unique biomineralogical scenarios discovered in these ancient-in-origin organisms.

As early arthropods, trilobites are widely thought to have had chitinous exoskeletons, because the aminopolysaccharide chitin (C8H13O5N)n is a ubiquitous structural organic component of arthropod cuticle. However, despite the abundance of trilobites in the lower Paleozoic fossil record, chitin has never been detected in these fossils. Here we report detection of chitin in an Olenellus trilobite from the Pyramid Shale Member of the Carrara Formation (514.5-506.5 Ma) at Emigrant Pass, California, USA. By analyzing trilobite cuticle with calcofluor white (CFW) fluorescent staining, Fourier transform infrared (FTIR) spectroscopy, and electrospray-ionization mass spectroscopy (ESI-MS), we found spectral peaks indicative of d-glucosamine, the monomer of chitin. This result contrasts with many previous analyses that produced a negative detection of chitin in a variety of fossils and is consistent with literature published in recent decades reporting positive chitin detections in fossils using modern analytical techniques. Our result appears to demonstrate that chitin might be able to survive in arthropod cuticle longer than previously confirmed, despite conditions of low-grade metamorphism. Because chitin is widely found as a major structural component of many eukaryotes, including a large portion of limestone-building marine invertebrates, the decay timescale of this molecule is fundamentally important for characterizing global biogeochemical cycling of carbon and nitrogen. The array of techniques now available for detecting this extremely common biopolymer may allow new insights into both the structure and function of many fossilized organisms, as well as improved determination of the taphonomic factors governing decay rates of common organic compounds.

This study investigated the photodegradation process of Rhodamine B (RhB) and acetaminophen (ACE) using a novel N-S-codoped carbon microporous and three-dimensional (3D) architecture (NSC) derived from a spongin scaffold of poriferan origin. For the first time NSC-CuWO4 was synthesized by converting a ready to use 3D microfibrous spongin scaffold through co-precipitation and in-situ pyrolysis. Subsequently, silver nanoparticles (Ag NPs) were incorporated to create the NSC-CuWO4@Ag hybrid material. The 3D architectural morphology and N-S-codoping of the material provided advantages in terms of high charge-separation efficiency, charge transfer, mass transfer, and optical absorption during the photoreaction. Under visible-light irradiation, NSC-CuWO4@Ag hybrid nanomaterial demonstrated excellent photocatalytic efficiency, degrading over 91 % of ACE and 97 % of RhB within 30 minutes. The photochemical tests revealed that electrons generated by irradiated CuWO4@Ag material transferred to the NSC microporous structure, facilitating the reduction of O-2 and the production of H2O2 in an aqueous environment. This process significantly boosted the photocatalytic activity of CuWO4. The MTT assay indicated that NSC-CuWO4@Ag nanoparticles (NPs) showed the highest cell viability. This is attributed to the silver NPs, which enhance biocompatibility and reduce the cytotoxic effects associated with carbonized spongin-derived NSC. This hybrid nanocomposite demonstrates excellent biocompatibility, making it a promising candidate for biomedical applications that require minimal cellular toxicity.

Demosponges (phylum Porifera) are among the first multicellular organisms on the planet and represent a unique archive of biosilica-based skeletal structures with species-specific microstructures called spicules. With more than 80 morphotypes, this class of sponges is recognized as a unique source of amorphous silica with superficial ornamentation patterned by organic phases. In this study, we investigated spicules of selected representatives of the family Geodiidae (order Tetractinellida), to identify F-actin-containing axial filaments within these 3D skeletal microconstructs defined as oxyspherasters and sterrasters. Their desilicification using 10% HF leads to isolation of multifilamentous, radially oriented organic matrices, which resemble the shape and size of the original spicules. Our data show that highly specific indicators of F-actin such as iFluorTM 594-Phalloidin, iFluorTM 488-Phalloidin, as well as iFluorTM 350-Phalloidin unambiguously confirm its localization within demineralized oxyspherasters and sterrasters of 11 diverse demosponges species belonging to the subfamily Geodiinae (genera Geodia, Rhabdastrella) and the subfamily Erylinae (genera Caminella, Caminus, Erylus, Pachymatisma). Well-defined periodicity in Geodia cydonium sterrasters actin filaments has been observed using atomic force microscopy (AFM) for the first time. The findings of F-actin as a possible pattern driver in spicules of geodiids brings additional light to our knowledge of spiculogenesis in this group. However, no specific actin structures were found between the geodiid subfamilies or genera thereby suggesting a common actin process, present already at the emergence of the family (~170 million years ago).

This study examines the effect of incorporating single-walled carbon nanotubes (SWCNTs) and multi-walled carbon nanotubes (MWCNTs) into carbon fiber reinforced polymers (CFRPs) based on Elium (R) thermoplastic acrylic resin and investigates the relationship between the studied properties. SWCNTs exhibited better dispersion in the matrix, which leads to better electrical conductivity (2.72 +/- 0.34 S/m) and impact resistance (154 +/- 14.6 kJ/m2) compared to MWCNTs. Microstructural analysis revealed a defect-free architecture of the SWCNT-modified laminates, while the MWCNT laminates showed small voids and agglomerates. The increased dispersion and interconnectivity of the SWCNTs contribute to an EMI shielding efficiency of 24.6 dB, a 30% improvement over the unmodified samples. These findings highlight the potential of SWCNTs to improve the multifunctional properties of thermoplastic CFRPs, including mechanical strength, electrical performance and EMI shielding capability, making them highly suitable for advanced aerospace, electronics and power applications. Moreover, the recyclability and lightweight nature of the Elium (R) resin matrix make these composites environmentally friendly and an alternative to traditional materials in a variety of industrial contexts.

The emergence of SARS-CoV 2 caused the COVID-19 pandemic, resulting in numerous global infections and deaths. In particular, people with metabolic diseases display an increased risk of severe COVID 19 and a fatal outcome. Treatment options for severe cases are limited, and the appearance of new virus variants complicates the development of novel therapies. To better manage viral infections like COVID 19, new therapeutic approaches are needed. Marine sponges offer a natural and renewable source of unique bioactive agents. These sponges produce secondary metabolites with various effects, including anti-viral, anti-inflammatory, and anti-tumorigenic properties. In the current study, we investigated the effect of five different marine sponge-derived secondary metabolites (four bromotyrosines and one sesquiterpenoid hydroquinone). Two of these, Avarol and Acetyl-dibromoverongiaquinol reduced the expression of ACE2, the main receptor for SARS-CoV 2, and the alternative receptor NRP1. Moreover, these substances derived from sponges demonstrated the ability to diminish the virus titer in SARS-CoV 2-infected cells, especially concerning the Omicron lineage. However, the reduction was not substantial enough to expect a significant impact on infected humans. Consequently, the investigated sponge-derived secondary metabolites are not likely to be effective to treat COVID 19 as a stand-alone therapy.

The study represents new bioanalytical characterization of mainly organic components of the poorly investigated extracellular polymeric substances (EPS) of the enigmatic diatom Didymosphenia geminata, an invasive, worldwide expanding species endangering diverse ecosystems. This microalga attaches its siliceous cells to rocky substrates using fibrous stalks, which are made of an EPS-based matrix stabilized by crystalline calcite. The EPS were analyzed using selected methods, including microscopic, spectroscopic, and spectrometric techniques. We identified diverse types of biomolecules. The presence of lipids, condensed aromatics, and heteroaromatic compounds in the EPS has been confirmed using high-resolution mass spectrometry (HR-MS). Additionally, both sulfur-containing functionalities and carboxylic acids were determined too using infrared (IR) spectroscopy and nuclear magnetic resonance (NMR) spectroscopy. For the first time, lignin compounds have been detected as one of the components of the EPS of the D. geminata diatom, using HR-MS and fluorescence microscopy (FM) in combination with specific staining techniques. By increasing the understanding of the chemistry and structural features of the stalks, we aim to develop potential applications and methods for removing these stalks from affected regions in the future, or, alternatively, to use them as a large-scale source of sustainable biocomposite material.

Supercapacitors (SCs) are emerging as promising energy storage technology, thanks to their high-power density, rapid charging/discharging capabilities, and extended cycle life. The quest for enhanced performance, particularly in terms of energy density, has driven extensive exploration into innovative electrode materials to bolster performance. This study focuses on recent advancements in CoMoO4 (CMO) with engineered architectures serving as electrodes for high-performance SCs. A distinct advantage lies in the ability of Co and Mo ions to exist in a range of oxidation states, promising increased energy density, enhanced cycling stability, and prolonged discharge time for SCs. These advancements encompass α, β, and hydrated (H)-CMO with adjusted electronic structures and adopting unique morphologies. Despite the longstanding study of CMO architectures, their inherent low conductivity and volume fluctuations during operation hinder further SC applications. To overcome these challenges, the integration of various materials has been explored. Concurrently, incorporating conductive materials (polymers, metal elements, amorphous carbon, graphene, carbon nanotubes, etc.) and introducing metals, heteroatoms, and defects into the electrode matrix (oxygen vacancies, heterojunctions) have proven effective in enhancing electrochemical performance. This review aims to provide recommendations for optimizing the performance of CMO-based SC electrode materials by manipulating the conductivity and reactivity of CMO. As a guiding principle, optimizing crystallite size, morphology, and synthesis and deposition strategies is crucial for the sustainable development of CMO-based nano-architecture designs for thick and flexible electrodes in prospective practical electronic storage devices.