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An ultra-sensitive electrochemical immunosensor for detecting carcinoembryonic antigen was prepared. Graphene oxide-gold was used as the substrate modifier of the sandwich immunosensor. The high conductivity of graphene oxide effectively enhanced the electron transfer rate. The large specific surface area of graphene and the biocompatibility of gold nanoparticles increased the number of primary antibodies. The bovine serum albumin coated silver – platinum composite was used as a secondary antibody tag to prepare signal probes. The excellent biocompatibility of bovine serum albumin increased the number of secondary antibody connections. Silver nanoparticles increased the speed of electron transfer, and platinum further enhanced electrochemical sensing capabilities by catalyzing hydrogen peroxide. The immunosensor showed good performance for detecting carcinoembryonic antigen. Under the optimal conditions, the dynamic response range for carcinoembryonic antigen was from 0.005 ng·mL−1 to 100 ng·mL−1 with a detection limit of 0.76 pg·mL−1. The immunosensor also shown high selectivity, suitable stability, and good reproducibility, which provides new capabilities for clinical carcinoembryonic antigen detection. [ABSTRACT FROM AUTHOR]

In this work, we report for the first time a simple approach to fabricate 3D reduced graphene oxide/boron nitride (rGO/BN) sponges with no additional chemical cross-linkers. Encouragingly, such sponge possesses higher compressibility and better recoverability in both air and organic solvents as compared to the bare rGO sponge. The as-prepared rGO/BN sponge also exhibits excellent water resistance and high oil absorption capability, achieving up to 170 times its own weight toward a wide range of environmental contaminants. Especially, the absorbed oil can be easily removed by the absorption–squeezing process which is cost effective and environmental friendly for oil collection. Most importantly, the underlying reasons for the remarkable mechanical properties, excellent oil absorption capabilities have been analysed and revealed in depth. These exceptional characteristics together with the ease of scalable synthesis make the as-prepared 3D rGO/BN sponge show many promising applications ranging from tissue engineering, sensors, catalysis, energy storage and conversion to environmental remediation. [ABSTRACT FROM AUTHOR]

Reduced graphene oxide (rGO)/boron nitride (BN) composite films were successfully fabricated by facile vacuum filtration and subsequent thermal treatment. Their morphology, structure and electrochemical performance were systematically characterized by field emission scanning electron microscopy, transmission electron microscopy, X-ray photoelectron spectroscopy, Raman spectroscopy, cyclic voltammetry, galvanostatic charge/discharge and electrochemical impedance spectroscopy. Importantly, the as-prepared rGO/BN composite film with a 2 wt.% BN content as binder-free anode material for lithium ion batteries (LIBs) exhibited a high reversible capacity of 278 mAh·g −1 at a high current density of 100 mA·g −1 , high rate capability, and high capacity retention over the first 200 cycles. The enhanced electrochemical performances of rGO/BN composite film are attributed to the unique structure and the synergistic effects between layered BN and graphene, which favored electrolyte penetration and buffered the volume expansion during the lithiation and delithiation process. In addition, this work not only provides a versatile strategy for fabrication of other graphene-based films, but also shows the potential promise of rGO/BN composite film for other energy storage devices. [ABSTRACT FROM AUTHOR]

• Reduce graphene oxide/MoS2 @ polyaniline have a novel structure nanosheet arrays arranged. • We explored the optimal amount of aniline added. It has an excellent and film thickness and conductivity to improve the sensitivity of detection. • Under the optimal conditions, the prepared immunosensor exhibits acceptable reproducibility, selectivity and excellent stability. A three-dimensional array of reduced graphene oxide/MoS 2 @ polyaniline-layered nanosheets (denoted as rGO/MoS 2 @ PANI) has a novel structure of intercalated MoS 2 /PANI nanosheets arrays arranged on rGO that can be used as carcinoembryonic antigen (CEA) electrochemical immunosensors (detectors). In this graded nanosheet, the PANI was embedded in the MoS 2 interlayer. The MoS 2 /PANI nanosheets themselves limit volumetric changes when arranged as MoS 2 /PANI nanosheet arrays on rGO nanosheets to provide tight and sufficient heterogeneity. PANI locates on the interface itself and contains a large amount of –NH 2 that can bind many antibodies. Simultaneously, we investigated the optimal amount of aniline to add. We found that these arrays had excellent film thickness and conductivity for improving CEA detection sensitivity. The tested immunosensor achieved sensitive and specific detection of CEA, with a detection limit of 0.3 pg mL−1. Under the optimal conditions, the prepared immunosensor exhibited acceptable reproducibility and selectivity and excellent stability. Satisfactory results of human serum samples indicated the potential application of the immunosensor for clinical monitoring of tumor markers. [ABSTRACT FROM AUTHOR]