Fabrication of a New, Low-Cost, and Environment-Friendly Laccase-Based Biosensor by Electrospray Immobilization with Unprecedented Reuse and Storage Performances.

Mattea Carmen Castrovilli,Emanuela Tempesta,Lorenzo Avaldi,Jacopo Chiarinelli,Alessandra Del Giudice,Luciano Galantini,Maria Filomena Verrastro,Ludovica Gullo,Pietro Calandra,Nunzia Cicco,Diego Centonze,Antonella Cartoni,Paola Bolognesi,Paolo Plescia

doi:10.1021/acssuschemeng.1c07604

Abstract

The fabrication of enzyme-based biosensors has received much attention for their selectivity and sensitivity. In particular, laccase-based biosensors have attracted a lot of interest for their capacity to detect highly toxic molecules in the environment, becoming essential tools in the fields of white biotechnology and green chemistry. The manufacturing of a new, metal-free, laccase-based biosensor with unprecedented reuse and storage capabilities has been achieved in this work through the application of the electrospray deposition (ESD) methodology as the enzyme immobilization technique. Electrospray ionization (ESI) has been used for ambient soft-landing of laccase enzymes on a carbon substrate, employing sustainable chemistry. This study shows how the ESD technique can be successfully exploited for the fabrication of a new promising environment-friendly electrochemical amperometric laccase-based biosensor, with storage capability up to two months without any particular care and reuse performance up to 63 measurements on the same electrode just prepared and 20 measurements on the one-year-old electrode subjected to redeposition. The laccase-based biosensor has been tested for catechol detection in the linear range 2–100 μM, with a limit of detection of 1.7 μM, without interference from chrome, cadmium, arsenic, and zinc and without any memory effects.

Highlights

The fields of green chemistry and white biotechnology look at biocatalysts as cutting-edge technology, thanks to their ability to exploit the selectivity and low energy requirements of enzymes to create nontoxic biosensing devices
The immobilization procedure must preserve the maximum activity of the bioreceptor and improve the performance of the device in terms of storage and reuse, the latter being mandatory in order to reduce the pollution due to disposable devices
We first compared the collected data with the theoretical small-angle X-ray scattering (SAXS) profile calculated from the crystallographic structure of the laccase from Trametes versicolor available in the Protein Data Bank (PDB) entry 1GYC54. This structure, which includes a total of six glycosylation sites with three monosaccharide and three disaccharide units covalently attached to Asn residues, would predict a much smaller particle size with an Rg value of 22 Å and a maximum size of 70 Å

Summary

Introduction

The fields of green chemistry and white biotechnology look at biocatalysts as cutting-edge technology, thanks to their ability to exploit the selectivity and low energy requirements of enzymes to create nontoxic biosensing devices. In the construction of a successful performing enzymatic biosensor, many fundamental factors must be taken into consideration.[1] Among them, the choice of the correct immobilization method of the bioreceptor on the surface of the transduction system is considered a crucial one.[2,3] The immobilization procedure must preserve the maximum activity of the bioreceptor and improve the performance of the device in terms of storage and reuse, the latter being mandatory in order to reduce the pollution due to disposable devices. The immobilization procedure is capable of facilitating the recycling of enzymes, allowing a reduction in the cost of the biosensor production process by up to 50%.4. The maintenance of the catalytically active structure is a key factor to maximize the stability and reactivity of the enzyme in its immobilized state.[5−10]

Methods

Results

Conclusion