Flavio Pendolino

The structural change of graphene oxide in a methanol dispersion

Graphene oxide is a derivative of graphene which contains oxygen domains. Its debatable structure depends on the specific functional groups bonded to the graphene basal plane which have an impact on its reactivity. Here, we report the influence of methanol which affects the functionalization of pristine graphene differently to water.

Low-Cost Synthesis of Smart Biocompatible Graphene Oxide Reduced Species by Means of GFP

The aim of this work is focused on the engineering of biocompatible complex systems composed of an inorganic and bio part. Graphene oxide (GO) and/or graphite oxide (GtO) were taken into account as potential substrates to the linkage of the protein such as Anemonia sulcata recombinant green fluorescent protein (rAsGFP). The complex system is obtained through a reduction process between GO/GtO and rAsGFP archiving an environmentally friendly biosynthesis. Spectroscopic measurements support the formation of reduced species. In particular, photoluminescence shows a change in the activity of the protein when a bond is formed, highlighted by a loss of the maximum emission signal of rAsGFP and a redshift of the maximum absorption peak of the GO/GtO species. Moreover, the hemolysis assay reveals a lower value in the presence of less oxidized graphene species providing evidence for a biocompatible material. This singular aspect can be approached as a promising method for circulating pharmaceutical preparations via intravenous administration in the field of drug delivery.

Graphene Oxide in Environmental Remediation Process

Since the water crisis is facing, purification methods and removal technology are the object of discussion. Carbon-based materials are largely employed as filters and in particular graphene oxide is considered for its exceptional physical chemical properties as a good candidate for the fabrication of innovative devices.

A case of chemical scalp burns after hair highlights: experimental evidence of oxidative injuries

Abstract Hair highlights are quite common procedures carried out in hair salons by using a mixture of a lightening powder containing persulfates with a suspension containing hydrogen peroxide: a representative case of chemical scalp burns is described as a consequence of this treatment. The aim of the paper is to demonstrate the strict relationship between the scalp damage and the commercial products used in a case of hair highlighting. The results of some chemical analyses have been reported, showing, in particular, that the chemical reactivity of the mixture changes in the time, thus strongly suggesting that the procedure for the application of the mixture is critical for the occurrence of possible accidents. The presence in the powder of chemical compounds bearing aliphatic chains as surfactants explains the appearance of dramatic symptoms after days due to a slow dissolution of the oxidant compounds in the stratum corneum of skin with no effect in reducing injury of palliative treatments. Safety suggestions and recommendations for producers and workers are also included.

Synthesis, Characterization and Models of Graphene Oxide

The chapter gives an overview of the most important synthetic methods to produce graphene oxide via wet chemistry. Brodie-Staudenmaier-Hummers and free-water based approaches are reported and where it is considered the influence of synthesis on the graphene oxide structure. Physical chemical and morphological characterisations are described in the second part of the chapter. In the last section, details of theoretical calculation and modelling of graphene oxide structures are presented.

Remediation Process by Graphene Oxide

In this chapter the remediation of water by means of graphene oxide is reported. The advantage of the use of this material is based on the amphiphilic character of graphene oxide which allows to remove inorganic and organic molecules at nanoscale range. In a remediation process, graphene oxide can be implemented as free-standing, functionalized or composite material, as well as, in solid or liquid phase. Lamellar or foam arrangement and graphene oxide dispersion are differently used to produce membrane or 3D structures to efficiently remove a broad range of natural and synthetic molecules/ions with high sensitivity. Thus, graphene oxide opens an unconventional scenario for nanopurification of industrial wastewater which are contaminated with hazardous molecules. This subject is a relatively new topic and we are witnessing its development as a feasible nano-adsorbent/removal material. The most updated progress in this field is reported and categorized.

Regulation and Environmental Aspects of Graphene Oxide

Applications of smart nanomaterials are expected to impact many aspects of life and promoting a substantial and advanced change in technologies. However, recently the toxicity of these very promising materials and their environmental impact has been questioned. Graphene oxide is not yet regulated by a specific normative, thus the parent definition for nanomaterials is adapted. This chapter presents the normative and regulations on the nanomaterials with particular attention for the EU area. Because of a legislative framework is not yet presented or incomplete, guidelines and definitions support normative in view of auxiliary results from scientific progress on smart nanomaterials. In addition, a provisorily ISO technical document is approaching to define and standardize the producers to work with a nano-object. As graphene oxide is a novel nanomaterial, environmental aspects, connected to its employment, are now limited and further scientific understanding is needed to establish the eventual health and ecosystem risks.