Ever since the discovery of graphene, its potential has been predicted for a number of applications in various fields such as electronics, sensors, environmental decontamination techniques, separations and biomedicine to name a few. Among various such fields, the research in graphene-based nanocomposites membranes is still in its infancy as there is not a significant research published in this field so far. However, interestingly this field is registering an exponentially upward trend recently. This review article provides a brief description of polymer nanocomposite membranes with graphene as one of the most indispensable components in the membranes. In this article, we describe in a systematic and comprehensive manner the most recent research published so far in the nanocomposite membranes with graphene and the most commonly used polymers namely the polysulfone and the cellulose derivatives. This article also describes the main applications of these polymeric membranes in the fuel cells and in water purification processes containing the current literature data as well as the authors' own research.

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Green bio-based polymeric membranes are rapidly emerging as materials of choice for a number of biomedical applications such as in the osseointegration processes. In this work, we report our preliminary studies on the covalent immobilization of sericin on to green cellulose membranes for potential applications in the osseointegration field. Initially, the surface of the cellulose acetate membrane was immobilized with the amino-propyl-triethoxysilane (APTS) functional group, while the protein was immobilized through glutaraldehyde that was used as a linker between amino-propyl-triethoxysilane and sericin. The functionalized membranes were thoroughly characterized by different characterization techniques such as infrared spectroscopy (FT-IR); Raman spectroscopy, x-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM) and thermogravimetric analysis (TGA/DTG). All these techniques confirmed the successful functionalization and uniform immobilization of the protein onto the membrane surface. Subsequently, the performance of the membranes was characterized both in terms of flows and retention of bovine serum albumin and haemoglobin in the case of immobilized protein membranes. The retention was found to be more than 90% after 90 minutes of process. Since in these membranes cases, their speed of degradation is essential in the physiological pH conditions, so the degradation was also studied over a period of three months and the degradation mechanism is also explained. Furthermore, the membrane functionalized with sericin has proven to hold great promise for application in bone regeneration.

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Magnesium (Mg)-based alloys have become an important category of materials that is attracting more and more attention due to their high potential use as orthopedic temporary implants. These alloys are a viable alternative to nondegradable metals implants in orthopedics. In this paper, a detailed overview covering alloy development and manufacturing techniques is described. Further, important attributes for Mg-based alloys involved in orthopedic implants fabrication, physiological and toxicological effects of each alloying element, mechanical properties, osteogenesis, and angiogenesis of Mg are presented. A section detailing the main biocompatible Mg-based alloys, with examples of mechanical properties, degradation behavior, and cytotoxicity tests related to in vitro experiments, is also provided. Special attention is given to animal testing, and the clinical translation is also reviewed, focusing on the main clinical cases that were conducted under human use approval.