Functionalized graphene-based materials for cementitious applications.

Graphene-based materials (GBM) are promising cementitious composite additives that can significantly improve the mechanical characteristics and durability of concrete due to their unique properties, such as high surface area and aspect ratio and excellent tensile strength, to name a few. To display their full potential, GBM have to be homogeneously dispersed into the aqueous environment of cement-based matrices. The present study addresses the issue of limited dispersibility in the aqueous media of GBM through the chemical functionalization of mono- and few-layer graphene structures with hydrophilic aryl sulfonate groups and shows that a series of mortar samples containing modified GBM exhibit increased flexural and compressive strength by up to 17% and 30%, respectively, compared to mortar references without additives.

Experimental Paradigm for the Assessment of the Non-pharmacological Mechanism of Action in Medical Device Classification: The Example of Glycerine as Laxative.

The evolution of medical devices has led to the introduction of medical devices that include "substances" and which, due to their presentation and sites of application may resemble medicinal products. The difference between substance-based medical devices and medicinal products lies in the proper definition of the principal mechanism of action. The major problem at the moment is the lack of a proper procedure for the demonstration of a mechanism that is "not pharmacological, immunological or metabolic." We aimed to design an experimental set up to demonstrate the difference between the mechanism of action of two substances used commonly for the treatment of constipation, lubiprostone (example of medicinal product) and glycerine (example of medical device). By implementing cellular models and molecular analyses we demonstrate the difference in their mechanism of action. This set up can be considered an example on the possibility to define a paradigm for the case by case study of the mechanism of action of substances and combination of substances in medical devices.

Insights into the definition of terms in European medical device regulation.

INTRODUCTION: Medical devices comprise apparatus/instruments, software, and materials with therapeutic activities obtained by principal mechanisms of action different from pharmacological, immunological and metabolic, which are proper of medicinal products. In this context the key for the distinction between medicinal products and devices lies in the correct interpretation of these terms, which, although defined in a guideline, are still not univocally interpreted. Areas covered: This article discusses the definitions of pharmacological and non-pharmacological mechanisms of action, such as the chemical and physical means. The aim is to give insights on the correct definition these terms in order to contribute to build the desired synergy between scientific and regulatory fields and promote a correct interpretation of the European regulatory framework as well as sustainable health and innovation. Expert commentary: We propose a series of definitions and a method to interpret those definitions within possible decision tree paradigm. Specifically, we propose to define the difference between the terms 'action' of a medical device compared to the 'mechanism of action' of such device. In any decisional procedure the correct interpretation of these and other correlated terms is needed to correctly assess whether a substance is a medicinal product or a medical device.