Chemically functionalized Eggs capsules of Sea Snail (ess) banded dye-murex for bioremediation applications

Abstract

among materials proposed in literature to remediate the environment, biohybrid composites at the interface between material science, chemistry and biology are the most promising. In this paper, we first contemplate the use of porous capsules, released by marine murex snails after eggs hatching, as a natural matrix capable of adsorbing organic pollutants. This study starts to investigate chemical and morphological features of this envisaging, unexplored protein material. Then, the chemical topography of egg capsules has been potentiated via a surface decoration with the polyphenol gallic acid, leading to enhance the bioremediation potential of the final biohybrid material. This moiety helped to give a huge activation of the adsorption towards a specific organic pollutant: the drug Tetracycline. The bioorganic methodology begins with bioconjugation via direct targeting of the exposed Lysine residues with polyphenol moieties. The material was morphologically investigated via high-resolution X-ray micro-computed tomography (HR X-ray μ-CT), and characterized using Raman spectroscopy, Fourier Transformed Infrared-attenuated total reflectance (FTIR-ATR), micro-IR, elemental, and BET analysis, after the bioorganic decoration. For the in vitro environmental remediation test, Tetracycline was chosen as a model drug molecule, and the specific adsorption was tested concerning the mass of the investigated material, different pH conditions (considering limit values), till evaluating the recycle of the material. The functionalization efficiently sparked the properties of the starting material, leading to an increase in the biosorption of the model urban pharmaceutical pollutant Tetracycline. Compared to the natural material, the functionalized matrix showed a sorbing capacity 12.5 times higher, leading to the sorption of about 25 mmol of Tetracycline per g of sorbent. In addition, the functionalized material remained active up to 5 sorption cycles. This outcome represents an achievement made from the combination of natural materials and Nature inspired molecular moieties to act as efficient platforms for self-cleaning, leading to environmental remediation.