Electrocatalytic Applications of Graphene–Metal Oxide Nanohybrid Materials

Development of state-of-the-art electrocatalysts using commercially available precursors with low cost is an essential step in the advancement of next-generation electrochemical energy storage/conversion systems. In this regard, noble metal-free and graphene-supported nanocomposites are of particular interest. Graphene-based nanocomposite is an excellent candidate as energy-device and sensor-related electrode materials, largely due to their high electrical conductivity, large specific surface area, high-speed electron/heat mobility, and reasonably good mechanical strength. Among many types of graphene-based composite materials, graphene–metal oxide nanohybrids hold great promise toward engineering efficient electrocatalysts and have attracted increasing interest in both scientific communities and industrial partners around the world. The goal of this chapter is primarily set on an overview of cutting-edge developments in graphene–metal oxide nanohybrid materials, with the recently reported results from worldwide research groups. This chapter is presented first with an introduction, followed by synthetic methods and structural characterization of nanocomposites, an emphasis on their applications in energy and sensor-related fields, and finally completed with brief conclusions and outlook

Recent advancement in the method of transdermal drug delivery system: A review

A transdermal patch is a medicated adhesive patch that is applied to the skin and used to deliver a particular amount of medication into the bloodstream through the skin. It aids in the recovery of an injured bodily part. The transdermal drug delivery system (TDDS) provides an alternative safe means of drug delivery to previous intrusive techniques. In the past, topically applied lotions and ointments were the most commonly utilised systems for dermatological issues. The fact that some of these formulations cause systemic side effects indicates that they are absorbed through the skin. All topically applied medication formulations intended to transport the active ingredient into the general circulation are included in the transdermal delivery system. To overcome the skin's formidable barrier to topical medication administration, several substances have been utilised. Because of their unique qualities, such as improved bioavailability, regulated pharmaceutical release, and improved patient compliance, TDDS have recently gained increased attention. The current review focuses on the various advancements in transdermal drug delivery, as well as the various available methods for preparing transdermal patches, characterization and assessment tools for transdermal patch preparation, patents, transdermal compound clinical trials, and drug approved and future applications of transdermal drug delivery systems. As a result, in recent years, the Transdermal Drug Delivery System has received a lot of attention

A facile molecularly imprinted polymer-based fluorometric assay for detection of histamine

Histamine is a biogenic amine naturally present in many body cells. It is also a contaminant that is mostly found in spoiled food. The consumption of foods containing high levels of histamine may lead to an allergy-like food poisoning. Analytical methods that can routinely screen histamine are thus urgently needed. In this paper, we developed a facile and cost-effective molecularly imprinted polymer (MIP)-based fluorometric assay to directly quantify histamine. Histamine-specific MIP nanoparticles (nanoMIPs) were synthesized using a modified solid-phase synthesis method. They were then immobilized in the wells of a microplate to bind the histamine in aqueous samples. After binding, o-phthaldialdehyde (OPA) was used to label the bound histamine, which converted the binding events into fluorescent signals. The obtained calibration curve of histamine showed a linear correlation ranging from 1.80 to 44.98 μM with the limit of detection of 1.80 μM. This method was successfully used to detect histamine in spiked diary milk with a recovery rate of more than 85%

Graphene-Paper Based Electrochemical Sensors

Graphene paper as a new form of graphene-supported nanomaterials has received worldwide attention since its first report in 2007. Due to their high flexibility, lightweight and good electrical conductivity, graphene papers have demonstrated the promising potential for crucial applications in electrochemical sensors and energy technologies among others. In this chapter, we present some examples to overview recent advances in the research and development of two-dimensional (2D) graphene papers as new materials for electrochemical sensors. The chapter covers the design, fabrication, functionalization and application evaluations of graphene papers. We first summarize the mainstream methods for fabrication of graphene papers/membranes, with the focus on chemical vapour deposition techniques and solution-processing assembly approaches. A large portion of this chapter is then devoted to the highlights of specific functionalization of graphene papers with polymer and nanoscale functional building blocks for electrochemical-sensing purposes. In terms of electrochemical-sensing applications, the emphasis is on enzyme-graphene and nanoparticle-graphene paper-based systems for the detection of glucose. We finally conclude this chapter with brief remarks and outlook