Amino acid-based, sustainable organic nanozyme for allergic biomolecule detection

The newly emerged organic nanozymes overcome the chronic issues associated with inorganic nanozymes due to their sustainable properties. However, several limitations have been identified from recently developed agricultural-centered, organic compound-based nanozymes, including a narrow variety of constituent materials and a relatively larger physical diameter due to the monotonous fabrication strategy hurdling its diverse application. To mitigate these limitations, a novel organic compound-based nanozyme with smaller physical dimensions and a wide range of materials is desired. Herein, the amino acid-based, sustainable organic nanozyme (OA nanozyme) is introduced, which exhibits peroxidase-like catalytic activity. A modified fabrication process based on single chelation/polymer entanglement was developed for fast (up to 3 hours) nanozyme fabrication resulting in a smaller physical diameter with homogenous morphology (within 100nm, D90), and a designated surface charge (negatively charged in neutral pH). This OA nanozyme exhibits decent kinetic profiles (Km = 0.009 mM, H2O2), and has been successfully used for detecting allergic biomolecules using surface charge interaction and achieved a limit of detection (LOD) of 21.37 pgmL-1, for histamine with higher selectivity, capable of sensing molecule within 3 minutes. It is envisioned that this amino acid-based organic nanozyme will be utilized for further sustainable applications.