Building block and rapid synthesis of catecholamines-inorganic nanoflowers with their peroxidase-mimicking and antimicrobial activities

Cagla Celik,Nilay Ildiz,Ismail Ocsoy

doi:10.1038/s41598-020-59699-5

Abstract

Protein incorporated flower-shaped hybrid nanostructures have received highly considerable attention due to their greatly enhanced catalytic activities and stabilities. Up to date, proteins, enzymes (mostly considered as proteins), and amino acids (as the building blocks of peptides and proteins) have been used as organic components of the hybrid nanoflowers. Herein, we present a rational strategy to rapidly form catecholamines (dopamine, epinephrine and norepinephrine)-copper ion (Cu2+) incorporated nanoflowers (cNFs) mostly in 3 hours and show their peroxidase-mimic catalytic, dye degradation and antimicrobial activities through Fenton-like reaction mechanism. We systematically studied effects of experimental parameters including catecholamine concentrations, reaction time and reaction pH values, on formation of the cNFs. We also explained that norepinephrine nanoflower (neNF) with its porous structure, high surface area, polar surface property behaves as an efficient Fenton agent by exhibiting highly much catalytic activities compared to dopamine nanoflower (dNF) and epinephrine nanoflower (epNF). We claim that the NFs formed using nonprotein molecules can be used in designing new generation nanobiocatalytics, antimicrobial agents, nanobiosensors and pharmaceutical products.

Highlights

Protein incorporated flower-shaped hybrid nanostructures have received highly considerable attention due to their greatly enhanced catalytic activities and stabilities
Among the catecholamines nanoflowers, dopamine and norepinephrine nanoflowers were almost formed in 3 hrs incubation owing to their structural similarities, but epinephrine nanoflower was obtained in 24 hrs
We demonstrated that dopamine nanoflower (dNF) as a model catecholamine was not form at pH 5 and below and at pH 10 and above due to positive and negative repulsions, respectively

Summary

Introduction

Protein incorporated flower-shaped hybrid nanostructures have received highly considerable attention due to their greatly enhanced catalytic activities and stabilities. We present a rational strategy to rapidly form catecholamines (dopamine, epinephrine and norepinephrine)-copper ion (Cu2+) incorporated nanoflowers (cNFs) mostly in 3 hours and show their peroxidase-mimic catalytic, dye degradation and antimicrobial activities through Fenton-like reaction mechanism. It is worthy to mention that while limited mobility of enzymes in immobilized form may increase their stabilities, it adversely affects catalytic activities of enzymes owing to their unfavourable conformation and serious mass transfer limitations occurred between enzymes and substrates[10,11,12] To address these disadvantages of modified or immobilized enzymes, fabrication of hybrid organic–inorganic nanoflowers (NFs) with greatly enhanced catalytic activities and stabilities were discovered by Zare and co-workers[13,14]. E. coli ATCC 35218 (Gram negative) and S. aureus ATCC 25923 (Gram positive) used as bacterial strains, and C. albicans ATCC 10231 used as fungi were obtained from Erciyes University Pharmaceutical Microbiology Laboratory collection

Methods

Results

Conclusion