Nitrogen-doped magnetic carbon nanoparticles as catalyst supports for efficient recovery and recycling

Palladium nanoparticles were deposited with high dispersion and stability on nitrogen-doped magnetic carbon nanoparticles by a simple impregnation method, and their catalytic performance was investigated for Heck, Suzuki, and Sonogashira coupling reactions.This work was supported by the Brain Korea 21 program of the Korean Ministry of Education, and the Hyperstructured Organic Materials Research Center is supported by the Korea Science and Engineering Foundation

Network-Level Structural Abnormalities of Cerebral Cortex in Type 1 Diabetes Mellitus

Type 1 diabetes mellitus (T1DM) usually begins in childhood and adolescence and causes lifelong damage to several major organs including the brain. Despite increasing evidence of T1DM-induced structural deficits in cortical regions implicated in higher cognitive and emotional functions, little is known whether and how the structural connectivity between these regions is altered in the T1DM brain. Using inter-regional covariance of cortical thickness measurements from high-resolution T1-weighted magnetic resonance data, we examined the topological organizations of cortical structural networks in 81 T1DM patients and 38 healthy subjects. We found a relative absence of hierarchically high-level hubs in the prefrontal lobe of T1DM patients, which suggests ineffective top-down control of the prefrontal cortex in T1DM. Furthermore, inter-network connections between the strategic/executive control system and systems subserving other cortical functions including language and mnemonic/emotional processing were also less integrated in T1DM patients than in healthy individuals. The current results provide structural evidence for T1DM-related dysfunctional cortical organization, which specifically underlie the top-down cognitive control of language, memory, and emotion. © 2013 Lyoo et al

Human dopamine receptor nanovesicles for gate-potential modulators in high-performance field-effect transistor biosensors

The development of molecular detection that allows rapid responses with high sensitivity and selectivity remains challenging. Herein, we demonstrate the strategy of novel bio-nanotechnology to successfully fabricate high-performance dopamine (DA) biosensor using DA Receptor-containing uniform-particle-shaped Nanovesicles-immobilized Carboxylated poly(3,4-ethylenedioxythiophene) (CPEDOT) NTs (DRNCNs). DA molecules are commonly associated with serious diseases, such as Parkinson's and Alzheimer's diseases. For the first time, nanovesicles containing a human DA receptor D1 (hDRD1) were successfully constructed from HEK-293 cells, stably expressing hDRD1. The nanovesicles containing hDRD1 as gate-potential modulator on the conducting polymer (CP) nanomaterial transistors provided high-performance responses to DA molecule owing to their uniform, monodispersive morphologies and outstanding discrimination ability. Specifically, the DRNCNs were integrated into a liquid-ion gated field-effect transistor (FET) system via immobilization and attachment processes, leading to high sensitivity and excellent selectivity toward DA in liquid state. Unprecedentedly, the minimum detectable level (MDL) from the field-induced DA responses was as low as 10 pM in real- time, which is 10 times more sensitive than that of previously reported CP based-DA biosensors. Moreover, the FET-type DRNCN biosensor had a rapid response time (<1 s) and showed excellent selectivity in human serum

Transcranial direct current stimulation for online gamers: A prospective single-arm feasibility study

Aim: Excessive use of online games can have negative influences on mental health and daily functioning. Although the effects of transcranial direct current stimulation (tDCS) have been investigated for the treatment of addiction, it has not been evaluated for excessive online game use. This study aimed to investigate the feasibility and tolerability of tDCS over the dorsolateral prefrontal cortex (DLPFC) in online gamers. Methods: A total of 15 online gamers received 12 active tDCS sessions over the DLPFC (anodal left/cathodal right, 2 mA for 30 min, 3 times per week for 4 weeks). Before and after tDCS sessions, all participants underwent 18F-fluoro-2-deoxyglucose positron emission tomography scans and completed the Internet Addiction Test (IAT), Brief Self Control Scale (BSCS), and Beck Depression Inventory-II (BDI-II). Results: After tDCS sessions, weekly hours spent on games (p = .02) and scores of IAT (p < .001) and BDI-II (p = .01) were decreased, whereas BSCS score was increased (p = .01). Increases in self-control were associated with decreases in both addiction severity (p = .002) and time spent on games (p = .02). Moreover, abnormal right-greater-than-left asymmetry of regional cerebral glucose metabolism in the DLPFC was partially alleviated (p = .04). Conclusions: Our preliminary results suggest that tDCS may be useful for reducing online game use by improving interhemispheric balance of glucose metabolism in the DLPFC and enhancing self-control. Larger sham-controlled studies with longer follow-up period are warranted to validate the efficacy of tDCS in gamers

Current Trends in Sensors Based on Conducting Polymer Nanomaterials

nanomaterial

Polymer Nanomaterials in Biomedicine

Polymer nanomaterials have emerged as a promising class of materials within the field of biomedicine, owing to their unique physical, chemical, and biological properties [...

Conducting Polypyrrole Nanoparticles: Fabrication and Application

대표적인 전도성 고분자 중의 하나인 polypyrrole은 용이한 제조방법, 높은 전도도, 뛰어난 안정성 등과 같은 여러 가지 장점들 때문에 학문적/실용적 관점에서 상당한 연구가 진행되어 왔다. 최근에는 나노기술의 발전과 함께, polypyrrole로 구성된 구형 나노입자, 코어-셀 나노입자, 나노캡슐, 나노튜브, 나노복합재료 등의 서로 다른 형태를 지닌 나노재료들이 다양한 합성 방법들에 의해 제조될 수 있었다. 또한 이와 같은 나노재료들은 화학/바이오 센서, 슈퍼커패 시터, 액츄에이터, 탄소 전구체 등의 응용분야에 폭넓게 활용되어 왔다. 앞으로 관련 분야의 꾸준한 발전을 위해서 나 노입자의 크기 및 형태 조절, 체계적 물성 고찰과 같은 기초 연구들이 대량 생산, 응용장치 설계 및 제작과 같은 실용 화 연구들과 병행해서 지속적으로 수행되어야 할 것이다

Recent Advances in Nanostructured Conducting Polymers: from Synthesis to Practical Applications

Conducting polymers (CPs) have been widely studied to realize advanced technologies in various areas such as chemical and biosensors, catalysts, photovoltaic cells, batteries, supercapacitors, and others. In particular, hybridization of CPs with inorganic species has allowed the production of promising functional materials with improved performance in various applications. Consequently, many important studies on CPs have been carried out over the last decade, and numerous researchers remain attracted to CPs from a technological perspective. In this review, we provide a theoretical classification of fabrication techniques and a brief summary of the most recent developments in synthesis methods. We evaluate the efficacy and benefits of these methods for the preparation of pure CP nanomaterials and nanohybrids, presenting the newest trends from around the world with 205 references, most of which are from the last three years. Furthermore, we also evaluate the effects of various factors on the structures and properties of CP nanomaterials, citing a large variety of publications

A Field-Effect-Transistor Sensor Based on Polypyrrole Nanotubes Coupled with Heparin for Thrombin Detection

Carboxylated polypyrrole (CPPy) nanotubes were fabricated by the chemical copolymerization of pyrrole and pyrrole-3-carboxylic acid (P3CA) using cylindrical micelle templates. Importantly, the chemical functionality of CPPy nanotubes was determined by the input amount of P3CA and their redox property was also retained without degradation. A field-effect-transistor (FET) sensor platform was constructed using liquid-ion gating. CPPy nanotubes were anchored on an amine-functionalized Au interdigitated microelectrode substrate to achieve high quality contact at the polymer=metal interface. Subsequently, heparin was covalently conjugated with the CPPy nanotubes via a diamino linker. The FET sensor based on heparin-conjugated CPPy nanotubes showed specific and fast response upon exposure to thrombin protein.This work was supported by the Center for Advanced Materials Processing under the 21C Frontier Programs of the Ministry of Commerce, Industry and Energy

Nanostructured Electrode Materials for Electrochemical Capacitor Applications

The advent of novel organic and inorganic nanomaterials in recent years, particularly nanostructured carbons, conducting polymers, and metal oxides, has enabled the fabrication of various energy devices with enhanced performance. In this paper, we review in detail different nanomaterials used in the fabrication of electrochemical capacitor electrodes and also give a brief overview of electric double-layer capacitors, pseudocapacitors, and hybrid capacitors. From a materials point of view, the latest trends in electrochemical capacitor research are also discussed through extensive analysis of the literature and by highlighting notable research examples (published mostly since 2013). Finally, a perspective on next-generation capacitor technology is also given, including the challenges that lie ahead