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Novel two-dimensional Ti 3 C 2 MXene nanosheets were successfully prepared by etching Al from Ti 3 AlC 2 in LiF/HCl system. In order to further improve the dispersing property and electrical conductivity of Ti 3 C 2 nanosheets, Ti 3 C 2 /graphene oxide (Ti 3 C 2 -GO) nanocomposites were synthesized and applied for the fabrication of inkjet-printed hydrogen peroxide (H 2 O 2 ) sensor. The results of electrochemical characterization show that the prepared sensor maintains the biological activity of hemoglobin (Hb) and can be applied to the practical detection. The printed sensors display a dynamic range from 2 μM to 1 mM and a detection limit of 1.95 μM with a high sensitivity and excellent selectivity for H 2 O 2 determination. Therefore, the printable Ti 3 C 2 -GO nanocomposites are an excellent sensing platform for electrochemical determination.

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Nerve system diseases like Parkinson's disease, Huntington's disease, Alzheimer's disease, etc. seriously affect thousands of patients' lives every year, making them suffer from pains and inconvenience. Recently, biointerfaces between neural cells/tissues and polymer based biomaterials attracted worldwide attention due to the ability of polymer based biomaterials to serve as nerve conduits, drug carriers and neurites guidance platform in neuroregeneration. The role that bio-interface played and the way it interacted with neural tissues and cells have been thoroughly investigated by the researchers. In this paper we mainly focus on reviewing the bio-interface between nerve tissues/cells and advanced functional biocompatible polymers, such as conducting polymers and advanced carbon composite materials. These advanced polymers can provide combined interfacial stimulations including interfacial external neurotrophic factors (NTFs) delivery, electrical stimulation, surface guidance and molecules decoration to lesion cells and tissues to promote neuroregeneration in vitro and in vivo, and have contributed greatly to nerve diseases therapy. At the end of this review, the criteria of polymer based biomaterials utilized in neuroregeneration are summarized and the perspectives for future development of bio-interfaces are also discussed. Nerve system diseases like Parkinson's disease, Huntington's disease and Alzheimer's disease etc. seriously affect thousands of patients' lives every year, making the patients suffer from pains and inconvenience brought about by these diseases. Recently, bio-interface between neural cells/tissues and polymer based biomaterials attracted worldwide attention due to the ability of polymer based biomaterials to serve as nerve conduits, drug carrier and neurites guidance platform in neuroregeneration. The role that bio-interface played and the way it interacted with neural tissues and cells have been thoroughly investigated by the researchers.In this paper we mainly focus on reviewing bio-interface between nerve tissues/cells and advanced functional biocompatible polymers, such as conducting polymers and advanced carbon composites materials.. These advanced polymers can provide combined interfacial stimulations including interfacial NTFs delivery, electrical stimulation, surface guidance and molecules decoration to lesion cells and tissues to promote neuroregeneration in vitro and in vivo, and have contributed greatly to nerve diseases therapy. At the end of this review, the criteria of polymer based biomaterials utilized in neuroregeneration are summarized and the perspectives for future development of bio-interfaces are also discussed.

A label-free sensing platform is developed based on switching the structure of aptamer for highly sensitive and selective fluorescence detection of ochratoxin A (OTA). OTA induces the structure of aptamer, transforms into G-quadruplex and produces strong fluorescence in the presence of zinc(II)-protoporphyrin IX probe due to the specific bind to G-quadruplex. The simple method exhibits high sensitivity towards OTA with a detection limit of 0.03 nM and excellent selectivity over other mycotoxins. In addition, the successful detection of OTA in real samples represents a promising application in food safety.

This work describes the fabrication of high‐performance all‐solid‐state supercapacitors based on covalently‐anchored reduced graphene oxide (RGO)@polyaniline (PANI) composites via an inkjet printing method. Morphological and chemical characterization data show that PANI nanoparticles are immobilized on graphene oxide (GO) nanosheets via covalent bonds. Sandwich‐structured and interdigitated supercapacitors are fabricated by printing the as‐prepared GO@PANI composites on flexible substrates, followed by a chemical reduction. The devices display high volumetric capacitances (258.5 F cm−3 at 1 mV s−1 for sandwich‐structured ones and 554 F cm−3 at 1 mV s−1 for interdigitated ones) and excellent cycling retention (2000 cycles >90%). Moreover, at the bending state, there are no significant changes on the device capacitances, indicating their great flexibility. The high‐performance devices can be further designed to produce special geometries and patterns. The work may provide a novel strategy to fabricate RGO@PANI composite‐based supercapacitors, which allows the end users to precisely deposit active materials according to their designs, for miniature and wearable electronics.

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This work describes the fabrication of hierarchical 3D Nafion enhanced carbon aerogels (NECAGs) for sensing applications via a fast freeze drying method. Graphene oxide, multiwalled carbon nanotubes and Nafion were mixed and extruded into liquid nitrogen followed by the removal of ice crystals by freeze drying. The addition of Nafion enhanced the mechanical strength of NECAGs and effective control of the cellular morphology and pore size was achieved. The resultant NECAGs demonstrated high strength, low density, and high specific surface area and can achieve a modulus of 20 kPa, an electrical conductivity of 140 S m(-1), and a specific capacity of 136.8 F g(-1) after reduction. Therefore, NECAG monoliths performed well as a gas sensor and as a biosensor with high sensitivity and selectivity. The remarkable sensitivity of 8.52 × 10(3)μA mM(-1) cm(-2) was obtained in dopamine (DA) detection, which is two orders of magnitude better than the literature reported values using graphene aerogel electrodes made from a porous Ni template. These outstanding properties make the NECAG a promising electrode candidate for a wide range of applications. Further in-depth investigations are being undertaken to probe the structure-property relationship of NECAG monoliths prepared under various conditions.