Dentistry waste Treatment through enzymatic fuel cells

Abstract

Objective. Although waste is traditionally assessed as a polluting thing which need to be reduced or lessened, its management is a necessity wherever human beings live. Every year, global energy request increases. While oil products actually fulfil the great part of the energy demand, the growing difficulty in meeting it and, as a consequence, all the pollution and global warming problems are driving scientific research to an alternative and renewable energy. Waste contain a significant energy amount; if we could employ them and convert them into a reusable form, we might provide either to supply clean energy and to resolve the waste global problem. This issue is felt in a dental surgery too, because it concerns dangerous and infectious-risk waste disposal. The possibility of the employment of pieces of waste and consequently of their inside energy converting can represent a turning point in the clear energy field, gaining an enormous benefit for the environment and significantly lowering waste management costs. In recent years, Enzymatic Biofuel Cells (EFC), with substantial and green advantages have become a promising power source being distinguishable among the alternative energy conversion systems. Nowadays, since fossil fuel depletion and global climate change have started to threaten our existence and future, extensive research has been devoted on finding alternative energy resources and developing more efficient and environmentally friendly processes for energy storage and conversion.
Material and methods. Material employed (purchased by Sigma-Aldrich) were: Glucose oxidase (GOx), Nafion perfluorinated resin solution at 5% in a mixture of lower aliphatic alcohols and water, Polyethylene oxide. Stock solutions of D (+) glucose were prepared in a 0.1 M phosphate buffer solution and stored at 4 °C for at least 24 h before use. Carbon cloth electrode ELAT HT 140 E-W with a platinum loading of 5 gm-2 was purchased by E-Tek. Electrospun Nafion fibers were obtained as follows. Scanning electron microscopy was used to characterize the electrode morphologies.
Results. The current work focuses on enzymatic biological fuel cells (EFC), which are designed to convert the chemical energy of the fuel into electricity in a sustainable manner. The aim of our study is to develop enzymatic fuel cells using the infectious-risk special waste, such as blood and saliva, as fuels. Considering that blood contains glucose, the EFC devices development can be developed through the preparation of a glucose-oxidized (GOx) based bioanode, immobilized on an electrode surface.
Conclusion. During our research we developed an Enzimatic Fuel Cell prototype and we evaluated its ability to harvest energy from the blood and the saliva inside the risk-infectious medical waste and to employ it in order one day to help the energy requirements of a consulting room. This device is based on GOx as biocatalyst and either Nafion or low cost membranes based on polyaromatic polymers were used as polymer electrolytes. Moreover, we also have explored the performance of single chamber configuration, which directly eliminates the use of membranes, to assess the applicability of EFCs for dentistry waste management.