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The Ebola virus transmits a highly contagious, frequently fatal human disease for which there is no specific antiviral treatment. Therefore, rapid, accurate, and early diagnosis of Ebola virus disease (EVD) is critical to public health containment efforts, particularly in developing countries where resources are few and EVD is endemic. We have developed a reduced graphene oxide-based field-effect transistor method for real-time detection of the Ebola virus antigen. This method uses the attractive semiconductor characteristics of graphene-based material, and instantaneously yields highly sensitive and specific detection of Ebola glycoprotein. The feasibility of this method for clinical application in point-of-care technology is evaluated using Ebola glycoprotein suspended in diluted PBS buffer, human serum, and plasma. These results demonstrate the successful fabrication of a promising field-effect transistor biosensor for EVD diagnosis.

Lung transplantation in Taiwan began in 1991, but the experience was limited and diverse in the early years. We examined the cumulative institutional experience of the largest lung transplant cohort in Taiwan. Methods: A retrospective review of lung transplantations performed at a single institution from December 1995 through August 2016 was conducted. For comparative purposes, the cohort was divided into halves, with an early group (undergoing lung transplantation in the first decade) vs a late group (undergoing lung transplantation in the second decade). Standardized donor selection, organ procurement, and preservation protocols for brain-dead donors were applied. The outcomes measured were 30-day mortality and actuarial survival using the Kaplan–Meier method. Results: The cohort included 50 recipients in the early group and 42 recipients in the late group. Compared with the early group, recipients in the late group were significantly older (38.8 ± 11.6 vs 44.8 ± 13.4 years, p = 0.024) and more of them required mechanical ventilation before transplant (26.0% vs 66.7%, p

Gastric cancer is the fourth most common type of cancer globally and accounts for the second highest cancer-associated mortality rate in the world. Current treatment strategies for gastric cancer include surgery, radiotherapy, chemotherapy and targeted therapy. Intraperitoneal (IP) chemotherapy may increase the IP concentrations of chemotherapy drugs and reduce the systemic toxicity. At present, IP chemotherapy is used to treat patients with advanced gastric cancer, which has a high rate of peritoneal recurrence. The present study evaluated the feasibility of using docetaxel, cisplatin and fluorouracil (DCF) in an IP and intravenous (IV) dual chemotherapy regimen for the treatment of advanced gastric cancer. The treatment-associated adverse reactions and preliminary efficacy were reported. The first dose level utilized the full dose of DCF: Docetaxel, day one, 45 mg/m2 (IP) and day eight, 30 mg/m2 (IV); cisplatin (DDP), day one, 75 mg/m2 (IP); and fluorouracil (FU), days one to five, 750 mg/m2 (continuous IV). A total of six patients were treated at this level and two patients withdrew due to serious adverse reactions. Taking into account that the the tolerated doses used in combination regimens for Eastern populations are lower than that of the corresponding doses for Western populations, the dosages of the three drugs were all reduced by 20% in the application of the second dose level: Docetaxel, day one, 30 mg/m2 (IP) and day eight, 30 mg/m2 (IV); DDP, day two, 60 mg/m2 (IP); and FU, days one to five, 600 mg/m2 (continuous IV). A total of 26 patients were treated at this level. The main adverse reaction was bone marrow suppression, with grade III/IV neutropenia, leukopenia and febrile neutropenia accounting for 61.5, 53.8 and 19.2% of reactions, respectively, and grade III/IV anemia and thrombocytopenia accounting for 19.2 and 15.4% of reactions, respectively. Gastrointestinal adverse reactions primarily consisted of abdominal pain, with grade III/IV abdominal pain accounting for 30.8% of reactions. Only 7.7% of the patients withdrew from the treatment. The median time to progression (TTP) was five months [95% confidence interval (CI), 1.0-9.0 months], and the median overall survival (OS) was nine months (95% CI, 7.4-10.6 months). It was concluded that the DCF regimen with reduced dosage should be applied. IP and IV dual chemotherapy for the treatment of unresectable advanced gastric cancer is tolerated and demonstrated a good initial efficacy. Strategies for mitigating and reducing the adverse gastrointestinal reactions, particularly abdominal pain, may be the focus of future studies.

Scanning positive column of atmospheric-pressure glow discharge (AGD) plasma is proposed as an eco-friendly and cost-effective strategy toward the instantaneous (∼2 s) reduction of graphene oxide (GO) paper, further leading to a reduced graphene oxide (rGO) paper with unimpeded liquid permeation for high performance supercapacitors. Unlike previous finding that AGD plasma has no effect on GO, a well-designed AGD plasma containing scanning positive column region is demonstrated to be capable of converting GO paper to rGO paper. With the synergy of energetic electrons (electron density 1.03 × 1016 cm–3) and surface touch heating (translational temperature ∼800 K), restoration of graphene’s excellent electrical properties is realized, evidenced by a substantially (5 orders of magnitude) improved electrical conductivity. Moreover, the ultrafast reduction of oxygen functionalities results in the creation of exposed open channels and the expansion of graphene layers, leading to a rGO paper supercapacitor electr...

One of the most challenging issues in developing supercapacitor technology is the rational design and synthesis of active electrode materials, at the nanoscale, with favorable morphologies, reasonable porous structure, and excellent conductivity. By transforming a two-dimensional (2D) graphene sheet into a crumpled ball shape, a novel three-dimensional (3D) graphene structure with a large surface area and aggregation-resistant properties has been proposed as an active material in supercapacitors to address the issues associated with the restacking of 2D graphene sheets. To further improve the mass transport/electron transfer and address the issue of limited contact spots between the crumpled graphene balls (CGBs) or between the CGBs and the current collector, we report here a unique hierarchical nanohybrid with porous carbon nanotube (CNT)-networks decorated CGBs (p-CNTn/CGBs), which not only greatly improves the affinity for bridging the active material and the current collector but also maintains favorable features for supercapacitor applications, such as a large surface area, 3D hierarchical nanostructure, excellent electrical conductivity, and outstanding aggregation-resistance. The performance established on the p-CNTn/CGBs far exceeded the bare CGB and reduced graphene oxide (RGO) counterparts in terms of specific capacitance and rate capabilities.

An ultrasonic nebulizer-based spray method was developed to fabricate microshpere hybrids of crumpled graphene (CG) loading cobalt oxide (CoO). The as-prepared CoO/CG microsphere hybrids were used for constructing an enzymeless sensor for glucose detection in alkaline solution. The as-developed enzymeless glucose sensor exhibited rapid response (less than 3 s), high sensitivity (669.78 µA mM−1 cm−2), wide detection range (0.83 µM–8.61 mM), good reproducibility and stability, and low detection limit (0.46 µM) (S/N=3). Moreover, the detection of glucose in human blood serum samples with the as-developed sensor agreed well with the results obtained from commercial glucose meters.

We report a high-performance bi-functional electrocatalyst composed of 3D crumpled graphene (CG)–cobalt oxide nanohybrids. This is the first report on using CG coupled with nanocrystals as both oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) catalysts. The nitrogen-doped CG–CoO hybrid exhibits excellent catalytic activity and durability, making it a high-performance non-precious metal-based bi-functional catalyst for both ORR and OER.

Tetracycline antibiotics (TCs) are broad-spectrum antibiotics widely used in the prevention and treatment of human and poultry diseases, which can be frequently detected in natural water, soils and sediments. In this study, tetracycline was used as a model pollutant to investigate the performance and mechanism of ferrous sulfide in the removal of aqueous tetracycline antibiotics. Fe(II) species on the surface were proved to be crucial active sites of adsorption and reduction. S(-II) species couldn’t degrade tetracycline directly, but it promoted the circle of Fe(III)/Fe(II) as the other electron donor. Dissolve oxygen and pH of solution were crucial factors in transformation of mineral surface. Combined with the SEM, XPS and XRD analysis of the minerals before and after the reaction, it was found that the generated hydroxides were good to improve the mass transfer because the appearance of Fe(III) species reduced the electrostatic repulsion by changing pHzpc of the mineral surface. As a strong oxidant, The addition of Cr(VI) promoted the degradation of tetracycline under acidic conditions, but inhibited the degradation under medium alkaline conditions. The LC-MS analysis shown the degradation pathway of tetracycline is a process of gradually removing the electron-withdrawing group. Comparing to the higher mass-to-charge ratio of intermediate products from oxidative degradation, the removal of tetracycline was inferred to be reduction because the mass-to-charge ratio of the intermediate only decreased gradually in this study. The degradation pathway was to gradually remove the electron-withdrawing group according to the electrophilic ability.

Although aptamer has been demonstrated as an important probe for antibiotic determination, the selective sensing of different antibiotics is still a challenge due to their structure similarities and wide folding degrees of aptamer. Herein, a field-effect transistor using MoS2 nanosheet as the channel and an aptamer DNA (APT) with its configuration shaped by a complementary strand DNA (CS) is employed for kanamycin (KAN) determination. This probe structure contributes to an enhanced selectivity and reliability with reduced device-to-device variations. This MoS2/APT/CS sensor shows time-dependent performance in antibiotic sensing. Prolonged detection time (20 s–300 s) leads to an enhanced sensitivity (1.85–4.43 M-1) and a lower limit of detection (1.06–0.66 nM), while a shorter detection time leads to a broader linear working range. A new sensing mechanism relying on charge release from probe is proposed, which is based on the “replacement reaction” between KAN and APT-CS. This sensor exhibits an extremely high selectivity (selectivity coefficient of 12.8) to kanamycin over other antibiotics including streptomycin, tobramycin, amoxicillin, ciprofloxacin and chloramphenicol. This work demonstrates the merits of probe engineering in label-free antibiotic detection with FET sensor, which presents significant promises in sensitive and selective chemical and biological sensing.

Phosphate, due to its somatotrophic effect on organisms, can cause severe eutrophication with excessive content in water. Conventional methods for phosphate detection, which are based on complicated instruments, are time-consuming. Here we report a luminescent lanthanide functionalized coordination polymer (Eu@BUC-14) by doping Eu3+ cations to BUC-14 nanocrystals. This Eu3+ functionalized hybrid (Eu@BUC-14) presents excellent luminescence features of Eu3+ ion that originated from efficient energy transfer from the ligand. The detection results show that Eu@BUC-14 is a highly efficient luminescent probe for phosphate detection in aqueous solutions, exhibiting high sensitivity with a low detection limit of 0.88 μM and a short response time of within 5 min. More significantly, Eu@BUC-14 has a high specificity for PO43− over fifteen other pollutant anions and eleven metal cations. The sensing mechanism is proposed via an in-depth analysis of the interaction between PO43− and Eu3+. Simultaneously, it displays high adsorption ability toward PO43− (57.9 mg P/g), making it an outstanding multifunctional material. And the adsorption process plays an important role in preconcentration of PO43− which can lead to a quick fluorescent response with high quenching efficiency. The practicality of Eu@BUC-14 was also validated by sensing PO43− in real environment water samples.

Background: Bronchoscopic lung mapping is a multispot dye-marking technique, which should be performed under real-time fluoroscopic guidance and post-mapping computed tomographic reconstruction. This study aimed to investigate the feasibility of lung mapping followed by post-mapping computed tomography (CT) and additional needle localization in a cone bean CT (CBCT) room. Methods: Between February 1, 2018 and August 31, 2018, 11 consecutive patients presenting with 14 lung lesions underwent bronchoscopic lung mapping in a CBCT room followed by thoracoscopic surgery. The efficacy and safety of the procedure were assessed through a retrospective chart review. Results: The median size of the pulmonary lesions was 8.1 mm [interquartile range (IQR), 7.2–10.8 mm] with a median depth-to-size ratio (D-S) ratio of 2.43 (IQR, 1.56–2.79). Additional needle localizations were performed in 4 patients, of which 3 and 1 patients underwent dual localization with dye and microcoil and localization with dye only, respectively. The median total localization time was 28 min (IQR, 18–69 min), and the median radiation exposure was 345.0 mGy (IQR, 161.8–486.6 mGy). A total of 8 wedge resections, 5 segmentectomies, and 1 lobectomy were performed. The final pathological diagnoses were as follows: primary lung cancer (n=6), lung metastases (n=4), and benign lung lesions (n=4). No adverse events were observed, and the median length of postoperative stay was 4 days (IQR, 3–5 days). Conclusions: Bronchoscopic lung mapping followed by post-mapping CT and additional needle localization can be performed together in a single examination room equipped with a C-arm CBCT, and the results of localization are contributory to the surgery.

The influence of the partial substitution of Mo for Cr on phase composition and hydrogen storage characteristics of non-stoichiometric Laves phase TiCrB0.9-based alloys is investigated by X-ray diffraction (XRD), pressure composition isotherm (PCT), and scanning electron microscopy (SEM) characterizations. XRD tests reveal that the phase composition of the alloys gradually changes from single TiB1.07CrB1.93 Laves phase to the co-existence of Laves phase and Mo-based BCC phase with increasing substitution of Mo for Cr. The phase composition eventually transforms into a single Mo-based BCC phase when the amount of the substitution surpasses a certain level. PCT tests reveal that the maximum hydrogen storage capacity increases with increasing Mo content. The hydrogenation-induced phase changes are also greatly influenced by the substitution of Mo for Cr. SEM tests of the hydrided alloys show that the increasing Mo content enhances hydrogenation-induced pulverization. Finally, hydrogenation-induced phase changes during the course of activation are also investigated.

Graphene coupled with nanocrystals (NCs) represents a new type of hybrid nanostructure that has attracted wide attention in energy and sensing applications. The interaction between graphene and NCs provides the hybrids with additional properties, offering rich opportunities to tune the material structure and properties. This Perspective highlights some recent progress in the research on graphene–NC hybrid structures with a focus on their energy storage/conversion and sensing applications. The structural characteristics of graphene–NC hybrids and the advantages of coupling NCs with graphene are demonstrated and discussed. Recent studies have shown the great potential of graphene–NC hybrids to improve the performance of energy storage/conversion devices (e.g., Li ion batteries, supercapacitors, fuel cells, and solar cells) and sensing devices (e.g., chemical sensors, biosensors, and water sensors). Further understanding and development of graphene–NC hybrids could therefore help address the demand for new e...

A facile and reliable method has been developed to synthesize nanohybrids of anatase TiO2 nanoparticles-decorating carbon nanotubes (CNTs@TiO2). The nanohybrid displays a unique feature of having CNTs encapsulated inside and anatase TiO2 nanoparticles coating on the CNT surface. Comprehensive characterizations suggest that CNTs@TiO2 nanohybrids exhibit unique properties of CNTs and TiO2 nanoparticles with one-dimensional structure, excellent electrical conductivity, high surface area, and good biocompatibility. The electrochemical properties of CNTs@TiO2 nanohybrids were systematically investigated, it was revealed that the CNTs@TiO2 nanohybrids showed great promise as anode materials of microbial fuel cells (MFCs). Compared with pure TiO2 nanoparticles and CNTs alone, CNTs@TiO2 nanohybrids exhibited a much higher output current, power density, and Coulombic efficiency when used as anode materials of MFCs. The as-developed synthetic route opens up a new avenue for designing CNTs-based nanohybrid materials for various applications benefiting from the synergetic effect among constituents.

This work describes a promising strategy for large-scale fabrication of silicon (Si) nanotubes. The process began with preparation of silica nanotubes using rod-like NiN2H4 as a template and the resulting silica nanotubes were then converted to Si nanotubes by a thermal reduction process assisted with magnesium powder. The electrochemical properties of Si nanotubes were investigated as anode of lithium-ion batteries. It was demonstrated that the as-developed Si nanotubes showed significantly improved rate capability and long-term cycling performance compared with commercial silicon meshes. Keywords: Silicon nanotubes, Lithium-ion batteries, Anode

Background Endotracheal intubation and chest tube drainage are considered mandatory for thoracoscopic pulmonary resection. The management of peripheral lung nodules by tubeless uniportal thoracoscopic surgical repair has not been reported previously. Methods From October 2015 through January 2016, 30 consecutive patients with peripheral lung nodules underwent uniportal thoracoscopic wedge resection without endotracheal intubation and chest tube drainage (tubeless group). The clinical outcomes were compared with the outcomes in 30 consecutive patients with peripheral lung nodules who underwent uniportal thoracoscopic wedge resection with chest tube drainage from April through October 2015 (chest tube group). Results The demographic, anesthetic, and operative characteristics of the patients were comparable in both groups. No major adverse events occurred after operation. A small residual pneumothorax was noted in 12 (40.0%) patients at 6 hours and day 1 and in 2 (6.6%) patients on day 14 in the tubeless group. No patient required reintervention or readmission to the hospital. Patients in the tubeless group had lower pain scale scores on postoperative day 1 (mean, 1.0 vs 1.5, p = 0.012) and shorter postoperative hospital stays (mean, 3.1 days vs 4.4 days, p = 0.011) than did those in the chest tube group. Conclusions Tubeless uniportal thoracoscopic wedge resection is feasible and safe and may be a less invasive alternative for treating selected patients with peripheral lung nodules.

Background: The Da Vinci robotic system has been used to enhance the surgeon’s visualization and agility in lung cancer surgery, and thus facilitate refined dissection, knot tying and suturing. However, only a few case reports exist on performing a sleeve lobectomy with a robotic-assisted thoracoscopic surgery (RATS) technique. Here we describe our early experience performing RATS sleeve lobectomies. To our knowledge, this is the first study reporting a series of RATS sleeve lobectomies. Methods: The six consecutive NSCLC patients who underwent a RATS sleeve lobectomy between November 2013 and July 2015 at the National Taiwan University Hospital were enrolled in this study. The lobectomies were all performed by the same surgeon using a three-arm robotic system with an additional utility incision made for assistance and specimen retrieval. Results: Five patients were diagnosed with squamous cell carcinoma, while the sixth was diagnosed with a carcinoid tumor. The mean operation time was 436.7 [255–745] minutes. The mean postoperative intensive care unit (ICU) stay and hospital stay were 3.7 [1–11] and 11.3 [3–26] days, respectively. Two (33.3%; 2/6) morbidities were noted, including one pneumonia and one anastomosis stricture. There were no cases of mortality or of conversion to thoracotomy. Conclusions: Our experience performing a RATS sleeve lobectomy in the six patients demonstrated the feasibility of RATS in complex lung cancer surgeries. The three-dimensional vision and articulated joint instruments made robotic-assisted bronchial anastomosis easier under the endoscopic setting. Our experience suggests that RATS offers specific advantages with regard to accuracy and safety when performing sleeve lobectomies.

We report significant enhancement of CuO nanowire (NW) sensing performance at room temperature through the surface functionalization with SnO(2) nanocrystals (NCs). The sensitivity enhancement can be as high as ∼300% for detecting 1% NH(3) diluted in air. The improved sensitivity could be attributed to the electronic interaction between p-type CuO NWs and n-type SnO(2) NCs due to the formation of nanosized p-n junctions, which are highly sensitive to the surrounding gaseous environment and could effectively manipulate local charge carrier concentration. Our results suggest that the NC-NW structure is an attractive candidate for practical sensing applications, in view of its outstanding room-temperature sensitivity, excellent dynamic properties (rapid response and quick recovery), and flexibility in modulating the sensing performance (e.g., by adjusting the coverage of SnO(2) NCs on CuO NWs and doping of SnO(2) NCs).

Hybrid nanomaterials composed of carbon nanotubes (CNTs) and graphene could potentially display outstanding properties that are superior to either CNTs or graphene alone. However, the inherent CNT–graphene loose junctions present in the CNT–graphene composites synthesized by existing methods significantly hinder the realization of the full potential held by CNT–graphene hybrids. In this letter, we report on a brand-new, three-dimensional (3D) carbon nanostructure comprising few-layer graphene (FLG) sheets inherently connected with CNTs through sp2 carbons, resembling plant leaves (FLGs) growing on stems (CNTs). The resulting hybrid nanostructures were characterized using scanning electron microscopy, transmission electron microscopy (TEM), Raman spectroscopy, and X-ray photoelectron spectroscopy. The evolution of FLG sheets on CNTs was tracked by high-resolution TEM. Distinct from a random mixture of CNTs and graphene sheets (CNT+G) suffering from poor CNT–graphene contacts, our CNT–FLG structure has intr...

We report the fabrication of a highly sensitive field-effect transistor (FET) biosensor using thermally-reduced graphene oxide (TRGO) sheets functionalized with gold nanoparticle (NP)-antibody conjugates. Probe antibody was labeled on the surface of TRGO sheets through Au NPs and electrical detection of protein binding (Immunoglobulin G/IgG and anti-Immunoglobulin G/anti-IgG) was accomplished by FET and direct current (dc) measurements. The protein binding events induced significant changes in the resistance of the TRGO sheet, which is referred to as the sensor response. The dependence of the sensor response on the TRGO base resistance in the sensor and the antibody areal density on the TRGO sheet was systematically studied, from which a correlation of the sensor response with sensor parameters was found: the sensor response was more significant with larger TRGO base resistance and higher antibody areal density. The detection limit of the novel biosensor was around the 0.2 ng/mL level, which is among the best of reported carbon nanomaterial-based protein sensors and can be further optimized by tuning the sensor structure. Open image in new window

Synthesis of carbon nanowalls (CNWs) at atmospheric pressure is realized by using a negative normal glow discharge, which differs from prior low-pressure plasma-enhanced chemical vapor deposition methods for CNW growth and holds great potential for mass-production of CNWs. The glow discharge is characterized for electrical and optical properties. The resulting CNW structures are analyzed using transmission electron microscopy, scanning electron microscopy, and Raman spectroscopy. The CNW growth process is examined for effects of discharge regime, discharge duration (growth time), hydroxyl radicals (water vapor), and local current density. Possible CNW growth mechanism and critical process parameters to the CNW growth and evolution are identified. OH radicals play an essential role in the initial nucleation process, but excess OH radicals accelerate the oxidation of CNWs. For a fixed growth time, there exists an optimum feed gas relative humidity and an optimum current density (∼40% and ∼9.17 A/m2, respectively, in the current work) for the growth of large and less defective CNWs with a high degree of crystallinity. Results obtained in this study can be used to tailor final properties of the as-grown CNWs for various applications.

With the growing evidence of clinical benefit of minimally invasive esophagectomy (MIE) combined video-assisted thoracoscopic surgery (VATS) and laparoscopy procedures, we describe how these procedures can be performed with single-incision both in the abdominal and thoracic phases. Clinical observation of the midterm results has demonstrated its feasibility and benefit of relieving postoperative pain. However, the long-term impact on the survival of the patients requires to be evaluated in the future.

Lung abscess is a type of infectious pulmonary disease, which occurs because of infection and destruction of the pulmonary parenchyma with central necrosis, eventually leading to cavity formation. The characteristic finding of chest roentgenogram is an air-fluid level in the cavitary lesion. In the era without antibiotics, putrid lung abscess was a crushing condition. In the early decades of the 20 th century, Neuhof proposed open drainage procedure for infection control of lung abscess, which effectively decreased the mortality rate of lung abscess from 75% to 2.5%. Around 1946, due to the advent of antibiotic, treatment of acute lung abscess with systemic antibiotics showed satisfied outcome. Thereafter, patients received medical treatment with systemic antibiotics rather than surgical management. Medical therapy with systemic antibiotics had become the principal treatment of lung abscess since then. Currently primary management of lung abscess mainly involves proper systemic antibiotics, intensive care, and, if indicated, percutaneous tube thoracostomy drainage. Surgical management for lung abscess became a more challenging task, since indication, timing, and the proper procedure for lung abscess are not well established. Undoubtedly, surgical intervention, including pulmonary resection or decortication procedure, tends to be restricted to those refractories to intensive medical treatment, complicated by life-threatening hemoptysis, pyopneumothorax, or pleural empyema. The primary goal of surgical management is adequate control of the septic focus.

Novel nanomaterials, such as nanowires and carbon nanotubes (CNTs), have attracted considerable attention in electrical detection of chemical and biological species for clinical diagnosis and practical pharmaceutical applications during the past decade. [ 1–3 ] Electrical detection of biomolecules using nanomaterials can often achieve high sensitivity because nanomaterials are extremely sensitive to electronic perturbations in the surrounding environment. By using CNTs and CNT-based fi eldeffect transistors (FETs), biosensors have been demonstrated for the detection of protein binding [ 4–7 ] and DNA hybridization events. [ 8 , 9 ] The detection limit of reported CNT protein sensors is normally at 0.1–10 nM level, [ 2 , 5 , 10 ] and an improved detection limit could reach 1 ng/ml through cleaving the protein using an enzyme. [ 7 ] Although CNT devices are promising candidates for biosensors with high sensitivity, the variation in the device characteristics is an obstacle to the device reliability and the device sensitivity is still limited by surface area and electrical properties of CNTs. Graphene, a single layer of carbon atoms in a two-dimensional honeycomb lattice, has potential applications in the electrical detection of biological species due to their unique physical properties. [ 11–13 ] Intrinsic graphene is a zero-gap semiconductor that has remarkably high electron mobility ( ∼ 15 000 cm 2 ⋅ V − 1 ⋅ s − 1 ) at room temperature, [ 12 ] which is even higher than that of CNTs. [ 14 ] Although graphene has been explored for various applications, [ 15–26 ] there are only limited reports on graphenebased biosensors until recently. [ 27–33 ] For instance, large-sized graphene fi lm FETs were fabricated for the electrical detection of DNA hybridization; [ 27 ] graphene oxide (GO) was used in single-bacterium and label-free DNA sensors. [ 29 ] In addition, electrolyte-gated graphene FETs for electrical detection of pH and protein adsorption were reported. [ 30 ] Despite the sparse demonstration of graphene for biosensing applications, graphene-based FETs have not been reported for detection of protein binding (antibody to antigen) events. Because the carrier

Organic semiconductors (OSCs) have been extensively studied as sensing channel materials in field-effect transistors due to their unique charge transport properties. Stimulation caused by its environmental conditions can readily change the charge-carrier density and mobility of OSCs. Organic field-effect transistors (OFETs) can act as both signal transducers and signal amplifiers, which greatly simplifies the device structure. Over the past decades, various sensors based on OFETs have been developed, including physical sensors, chemical sensors, biosensors, and integrated sensor arrays with advanced functionalities. However, the performance of OFET-based sensors still needs to be improved to meet the requirements from various practical applications, such as high sensitivity, high selectivity, and rapid response speed. Tailoring molecular structures and micro/nanofilm structures of OSCs is a vital strategy for achieving better sensing performance. Modification of the dielectric layer and the semiconductor/dielectric interface is another approach for improving the sensor performance. Moreover, advanced sensory functionalities have been achieved by developing integrated device arrays. Here, a brief review of strategies used for improving the performance of OFET sensors is presented, which is expected to inspire and provide guidance for the design of future OFET sensors for various specific and practical applications.

This study demonstrates the electrical detection of protein binding by the introduction of Au nanoparticle–antibody conjugates in a carbon nanotube field effect transistor (CNTFET), in which the nanoparticle-functionalized carbon nanotube serves as the electrical conducting channel. Antibody (anti-horseradish peroxidase) and antigen (horseradish peroxidase) binding events lead to the amplitude change in the drain current, which can be sensitively detected by FET measurements. The sensor shows negligible response to mismatched proteins such as Immunoglobulin G (IgG), confirming the specificity of the biosensor. The reported CNTFET-based biosensor could be adapted to detect a variety of proteins for in vitro diagnostics.

Ag nanoparticles with different loadings were systematically coated onto uniformly aligned TiO2 nanorod arrays. The enhanced photocatalytic decay rates were found to increase linearly with the Ag nanoparticle load until a maximum photodecay rate was reached at 0.25 wt.% Ag loading, and then decrease almost linearly with further increasing Ag loading. A simple reaction model based on the Ag nanoparticle coverage and charge trapping is proposed, and the predicted results agree very well with the experimental results quantitatively. The effective lifetime of photogenerated holes due to the trapping of the Ag nanoparticles on the surface of TiO2 nanorods was estimated to be approximately three times that of pure TiO2 nanorods.

One-dimensional (1D) tungsten oxide crystals (wires, wire bundles, and tubes) were synthesized by a catalyst-free, physical evaporation–condensation process using a mini-arc plasma source. The growth process of the 1D tungsten oxide structure was deciphered through sequential scanning electron microscopy observations. Crystalline tungsten oxide grains form first and then rotate and align their positions to build up 1D crystals as wires, wire bundles, and tubes to minimize the surface energy because of the anisotropic nature of the tungsten oxide crystal. The influence of temperature and growth time on the crystal synthesis is analyzed.

Facile dry decoration of graphene oxide sheets with aerosol Ag nanocrystals synthesized from an arc plasma source has been demonstrated using an electrostatic force directed assembly technique at room temperature. The Ag nanocrystal-graphene oxide hybrid structure was characterized by transmission electron microscopy (TEM) and selected area diffraction. The ripening of Ag nanocrystals on a graphene oxide sheet was studied by consecutive TEM imaging of the same region on a sample after heating in Ar at elevated temperatures of 100 °C, 200 °C, and 300 °C. The average size of Ag nanocrystals increased and the number density decreased after the annealing process. In particular, migration and coalescence of Ag nanocrystals were observed at a temperature as low as 100 °C, suggesting a van der Waals interaction between the Ag nanocrystal and the graphene oxide sheet. The availability of affordable graphene-nanocrystal structures and their fundamental properties will open up new opportunities for nanoscience and nanotechnology and accelerate their applications.

Aerosol nanoparticles draw great attention due to their unique physico-chemical properties that can be harnessed for innovative applications as well as for their potential impact on public health and the environment. Microscopic characterization of these particles is critically important to understand the unique particle properties and their interaction with biological systems. Here we report on a simple and efficient method for size, morphology, and crystallinity analyses of aerosol nanoparticles through transmission electron microscopy (TEM). The method uses carbon nanotubes (CNTs) as the particle support on conventional TEM grids. The CNT support significantly improves the quality of high resolution TEM (HRTEM) imaging due to the unique properties of CNTs, the high probability of particles sitting at the edge of CNTs, and the minimization of the interference interaction between the electron beam and the supporting substrate. The improved HRTEM images are useful for detailed characterization of nanoparticles, and particularly suitable for analyzing core-shell nanoparticles.

The homogeneous GeS2-In2 S3-Csl glassy samples were prepared by conventional meltquenching method. When the molar ratio of In2 S3, to Csl remains 1, the mm-crystalline region can extend to the composition 0.4 GeS2 -0.3In2S3 0.3 Csl. And with the addition of Csl, the glassforming ability of this serial glass reaches its maximum at the composition 0.8 GeS2 −0.1 In2 S3 −0.1 Csl. According to the Raman spectra, the microstructure of these glasses is mainly constituted by [GeSt] and [lnS4−xIx] telrahedra, which are interconnected by the bridging sulfur atoms; meanwhile, the ethaneliked structural units [S3 Ge−GeS3] can be formed because of the lacking of sulfur;Cs+ ion, which is added from Csl, exists as the nearest neighbor of I-ion in the glassy network.

New chalcohalide glasses from GeS2–In2S3–CsCl pseudo-ternary system were prepared using the conventional melt-quenching method and its glass-forming region has been determined. The differences ΔT (TP − Tg) of partial glasses are large enough (>100 K) to permit the preparation of performs of considerable size. With the increased content of CsCl, the visible absorption edge (λvis) of these glasses indicates a distinct blue shift while a clear drop of their glass transition temperatures can be seen. The ultrafast non-linearity of partial glasses was measured using the Kerr shutter technique. The non-linear refractive index, n2, was estimated to be in the magnitude of 10−14 cm2/W. Widely transparent range, good glass-forming ability, higher χ(3) and large electronic ultrafast OKE response make these glasses the potential applications in current photonic fields.