The design of new composite materials using extreme biomimetics is of crucial importance for bioinspired materials science. Further progress in research and application of these new materials is impossible without understanding the mechanisms of formation, as well as structural features at the molecular and nano‐level. It presents a challenge to obtain a holistic understanding of the mechanisms underlying the interaction of organic and inorganic phases under conditions of harsh chemical reactions for biopolymers. Yet, an understanding of these mechanisms can lead to the development of unusual—but functional—hybrid materials. In this work, a key way of designing centimeter‐scale macroporous 3D composites, using renewable marine biopolymer spongin and a model industrial solution that simulates the highly toxic copper‐containing waste generated in the production of printed circuit boards worldwide, is proposed. A new spongin–atacamite composite material is developed and its structure is confirmed using neutron diffraction, X‐ray diffraction, high‐resolution transmission electron microscopy/selected‐area electron diffraction, X‐ray photoelectron spectroscopy, near‐edge X‐ray absorption fine structure spectroscopy, and electron paramagnetic resonance spectroscopy. The formation mechanism for this material is also proposed. This study provides experimental evidence suggesting multifunctional applicability of the designed composite in the development of 3D constructed sensors, catalysts, and antibacterial filter systems.

Modern scaffolding strategies include two key ways: to produce requested 3D constructs from corresponding precursors using technological tools, or simply use naturally already prefabricated scaffolds if they originate from renewable sources. Marine sponges inhabit oceans since the Precambrian. These ancient multicellular organisms possess a broad variety of evolutionary approved and ready to use skeletal structures, which seem to be well applicable as 3D scaffolds in diverse fields of modern bioinspired materials science, biomimetics and regenerative medicine. In this review, most attention is paid to biosilica-, chitin-, and spongin-based scaffolds of poriferan origin with respect to their potential use.

Molluscan shells are an example of a mineral-based biocomposite material, and most studies to date have focused on understanding their biomineralization mechanisms. Meanwhile, large amounts of these shells are produced as waste globally by seafood which is used by other industries as a source of biogenic calcium carbonates. In this study, we propose a simple methodological approach for isolation of Conchixes, the organic scaffolds that resemble the size and shapes of mollusks shells, using gentle EDTA-based demineralization of the shells. Such mineral-free biological materials have been extracted from selected representatives of marine and fresh water bivalves, as well as from marine and terrestrial gastropods under study. Key pathways to practical applications of molluscan conchixes with regards to pharmacy, cosmetics, feed and feed additives, biomedicine and bioinspired materials science are also discussed.

The renewable, proteinaceous, marine biopolymer spongin is yet the focus of modern research. The preparation of a magnetic three-dimensional (3D) spongin scaffold with nano-sized Fe3O4 cores is reported here for the first time. The formation of this magnetic spongin–Fe3O4 composite was characterized by X-ray diffraction (XRD), thermogravimetric analysis (TGA), differential thermal analysis (DTA) (TGA-DTA), vibrating sample magnetometer (VSM), Fourier-transform infrared spectroscopy (FTIR), and zeta potential analyses. Field emission scanning electron microscopy (FE-SEM) confirmed the formation of well-dispersed spherical nanoparticles tightly bound to the spongin scaffold. The magnetic spongin–Fe3O4 composite showed significant removal efficiency for two cationic dyes (i.e., crystal violet (CV) and methylene blue (MB)). Adsorption experiments revealed that the prepared material is a fast, high-capacity (77 mg/g), yet selective adsorbent for MB. This behavior was attributed to the creation of strong electrostatic interactions between the spongin–Fe3O4 and MB or CV, which was reflected by adsorption mechanism evaluations. The adsorption of MB and CV was found to be a function of pH, with maximum removal performance being observed over a wide pH range (pH = 5.5–11). In this work, we combined Fe3O4 nanoparticles and spongin scaffold properties into one unique composite, named magnetic spongin scaffold, in our attempt to create a sustainable absorbent for organic wastewater treatment. The appropriative mechanism of adsorption of the cationic dyes on a magnetic 3D spongin scaffold is proposed. Removal of organic dyes and other contaminants is essential to ensure healthy water and prevent various diseases. On the other hand, in many cases, dyes are used as models to demonstrate the adsorption properties of nanostructures. Due to the good absorption properties of magnetic spongin, it can be proposed as a green and uncomplicated adsorbent for the removal of different organic contaminants and, furthermore, as a carrier in drug delivery applications.

In vivo biomimetic biomineralization using living organisms known as biomineralizers is currently a major research trend. Industrially cultivated terrestrial snails, such as the common garden snail Cornu aspersum, represent a simple model organism that is ideal for use in experiments on the regeneration of the calcified shell after the excavation of a corresponding shell fragment. The mollusk’s artificially damaged shell is regenerated via the formation of an organic regenerative membrane, which serves as a native template for in vivo biocalcification. In this study, for the first time, a special plexiglass device for non-lethal fixation of living snails, enabling real-time monitoring of their ability to regenerate their shells using digital microscopy, has been proposed and tested. As an alternative to natural biomineralization using the mollusk’s own sources, we propose chitin- and collagen-based templates, which have been shown to be effectively calcified by living snails. The results indicate that the type of organic template used for in vivo biomineralization has a substantial effect on the nature of the mineral phases.