RESUMEN
The structural biopolymer spongin in the form of a 3D scaffold resembles in shape and size numerous species of industrially useful marine keratosan demosponges. Due to the large-scale aquaculture of these sponges worldwide, it represents a unique renewable source of biological material, which has already been successfully applied in biomedicine and bioinspired materials science. In the present study, spongin from the demosponge Hippospongia communis was used as a microporous template for the development of a new 3D composite containing goethite [α-FeO(OH)]. For this purpose, an extreme biomimetic technique using iron powder, crystalline iodine, and fibrous spongin was applied under laboratory conditions for the first time. The product was characterized using SEM and digital light microscopy, infrared and Raman spectroscopy, XRD, thermogravimetry (TG/DTG), and confocal micro X-ray fluorescence spectroscopy (CMXRF). A potential application of the obtained goethite-spongin composite in the electrochemical sensing of dopamine (DA) in human urine samples was investigated, with satisfactory recoveries (96% to 116%) being obtained.
RESUMEN
Marine sponges of the subclass Keratosa originated on our planet about 900 million years ago and represent evolutionarily ancient and hierarchically structured biological materials. One of them, proteinaceous spongin, is responsible for the formation of 3D structured fibrous skeletons and remains enigmatic with complex chemistry. The objective of this study was to investigate the interaction of spongin with iron ions in a marine environment due to biocorrosion, leading to the occurrence of lepidocrocite. For this purpose, a biomimetic approach for the development of a new lepidocrocite-containing 3D spongin scaffold under laboratory conditions at 24 °C using artificial seawater and iron is described for the first time. This method helps to obtain a new composite as "Iron-Spongin", which was characterized by infrared spectroscopy and thermogravimetry. Furthermore, sophisticated techniques such as X-ray fluorescence, microscope technique, and X-Ray diffraction were used to determine the structure. This research proposed a corresponding mechanism of lepidocrocite formation, which may be connected with the spongin amino acids functional groups. Moreover, the potential application of the biocomposite as an electrochemical dopamine sensor is proposed. The conducted research not only shows the mechanism or sensor properties of "Iron-spongin" but also opens the door to other applications of these multifunctional materials.
