查找使用阿拉丁产品的科研文献

Silica nanochannel array on co-electrodeposited graphene-carbon nanotubes 3D composite film for antifouling detection of uric acid in human serum and urine samples

Yu Cui,Shiyue Zhang,Xiaoyu Zhou,Fei Yan,Wei Hu

The present work reports a rapid and convenient electrochemical method for highly sensitive detection of uric acid (UA) by integration of vertically-ordered mesoporous silica film bearing amino groups (NH 2 -VMSF) and three-dimensional graphene-carbon nanotubes (3DG@CNT) composite film. 3DG@CNT and NH 2 -VMSF are successively modified onto the glassy carbon electrode (GCE) surface through a rather simple two-step controllable electrochemical deposition method. Arising from the large specific surface area, excellent electrocatalytic activity, and favorable mass transfer, 3DG@CNT co-electrodeposited onto the GCE surface could not only significantly improve the electrode performance, but also provide oxygen-containing groups for further functionalization. NH 2 -VMSF prepared by co-condensation approach using electrochemically assisted self-assembly method, possesses uniform pore size (∼2 nm in diameter) and positively charged surface, showing pronounced anionic permselectivity. Thanks to the electroactive 3DG@CNT inner layer and electrostatically preconcentrated NH 2 -VMSF outer layer, the proposed NH 2 -VMSF/3DG@CNT/GCE displays outstanding analytical performance towards UA with a wide linear range (0.1∼50 μM), a high sensitivity (1.66 µA·μM −1 ) and a low limit of detection (6.8 nM). Furthermore, considering the inherent anti-fouling property of NH 2 -VMSF, direct analysis of UA in human serum and urine samples is achieved with satisfactory recoveries.

Uniformly embedded PtCu alloy nanoparticles on mesoporous carbon nanospheres: a high-efficiency nanozyme for glucose detection

Wei Na,Li Xiaoyuan,Yin Hongjie,Sun Yunyun,Jia Huimin,Guan Huijuan,Gao Yuanhao

The construction of nanozyme-based electrochemical sensor with excellent analytical properties is urgently needed for non-enzymatic electrochemical sensing of glucose. In this work, we embed PtCu alloy nanoparticles on mesoporous carbon nanospheres (PtCu/MCNs) as nanozyme by strong electrostatic adsorption (SEA) method combined with high-temperature reduction for glucose detection. Characterization results show that PtCu alloy nanoparticles with average diameter of 3.7 nm are homogeneously embedded on MCNs. The formation mechanism of PtCu/MCNs was put forward based on strong electrostatic interaction. PtCu/MCNs(1:1) shows the highest electrocatalytic activity for glucose oxidation compared with other PtCu/MCNs. PtCu/MCNs(1:1)-based sensor displays low detection limit (0.0005 μM), high sensitivity (574.1 μA mM −1  cm −2 ), wide linear range (1 μM–5 mM), high selectivity and anti-interference for glucose analysis. Moreover, the as-constructed sensor has excellent reusability and stability. The above superior properties could be attributed to the homodisperse and firm combination with MCNs of small PtCu alloy nanoparticles, and the cooperative effect of Pt with Cu. The PtCu/MCNs(1:1)-based sensor exhibits satisfactory properties for the detection of glucose in beverages, indicating the application prospects of PtCu/MCNs for glucose determination in real samples. Graphical abstract

Pt/MXene-Based Flexible Wearable Non-Enzymatic Electrochemical Sensor for Continuous Glucose Detection in Sweat

Quan-Fu Li,Xu Chen,Hai Wang,Ming Liu,Hui-Ling Peng

Wearable non-invasive sensors facilitate the continuous measurement of glucose in sweat for the treatment and management of diabetes. However, the catalysis of glucose and sweat sampling are challenges in the development of efficient wearable glucose sensors. Herein, we report a flexible wearable non-enzymatic electrochemical sensor for continuous glucose detection in sweat. We synthesized a catalyst (Pt/MXene) by the hybridization of Pt nanoparticles onto MXene (Ti3C2Tx) nanosheets with a broad linear range of glucose detection (0–8 mmol/L) under neutral conditions. Furthermore, we optimized the structure of the sensor by immobilizing Pt/MXene with a conductive hydrogel to enhance the stability of the sensor. Based on Pt/MXene and the optimized structure, we fabricated a flexible wearable glucose sensor by integrating a microfluidic patch for sweat collection onto a flexible sensor. We evaluated the utility of the sensor for the detection of glucose in sweat, and the sensor could detect the glucose change with the replenishment and consumption of energy by the body, and a similar trend was observed in the blood. An in vivo glucose test in sweat indicated that the fabricated sensor is promising for the continuous measurement of glucose, which is essential for the treatment and management of diabetes.

Nonenzymatic Flexible Wearable Biosensors for Vitamin C Monitoring in Sweat

Chonghui Zhu,Yu Bing,Qidai Chen,Bo Pang,Juan Li,Tong Zhang

Nutritional status monitoring plays an important role in the maintenance of human health and disease prevention. Monitoring the intake of vitamins can support the improvement of diet behavior. In this work, a polyaniline (PANI) film-based nonenzymatic electrochemical sensor was prepared to track the vitamin C level in sweat. The PANI film was modified with organic acids (ethylformic acid, malic acid, tartaric acid, and phytic acid). The phytic acid-modified PANI film based on sensor has a wide detection range (0.5–500 μmol·L–1), high sensitivity (665.5 and 326.2 μA·(mmol·L–1)−1·cm–2), and low detection limit (0.17 μmol·L–1) toward vitamin C in sweat. The phytate enhances the band transport between PANI chains, which increases the electrical conductivity of the film to improve the electrochemical properties of the sensor. In addition, we monitored changes of vitamin C levels in human body after taking vitamin C pills by detecting sweat or saliva. The ability to track the pharmacological profile demonstrates the potential of PANI film-based sensors for applications in personalized nutritional intake and tracking. And a simple and portable vitamin C detection system was developed to improve the practicability of the sensor. This work provides an idea for the application of wearable electrochemical sensing devices in nutrition guidance.

Enzyme-free colorimetric detection of uric acid on the basis of MnO2 nanosheets - mediated oxidation of 3, 3′, 5, 5′- tetramethylbenzidine

Li Huang,Shangying Qin,Yuanjin Xu,Shiqi Cheng,Jin Yang,Yilin Wang

MnO 2 nanosheets (MnO 2 NSs) were prepared and used as both oxidant of 3, 3′, 5, 5′- tetramethylbenzidine (TMB) and recognizer of UA, a simple colorimetric approach for sensitive detection of uric acid (UA) was established. In the medium of weak acid, MnO 2 NSs exhibited strong oxidation capacity and could oxidize colorless TMB to generate a blue oxidation product (oxTMB) with an absorbance signal. However, the introduction of UA could inhibit MnO 2 NSs - mediated TMB oxidation and reduce the formation of oxTMB, resulting in the blue fading and the absorbance weakening. Under the conditions of incubation time 20 min, pH 3.0, TMB 0.5 mM, and MnO 2 NSs 50 μM, the decrease in absorbance was linearly dependent on UA concentration in the range of 0.5–30.0 μM with a detection limit of 0.21 μM. Furthermore, the approach has been applied for determining UA in human urine samples with recoveries between 93.1 and 102.4 % and relative standard deviation less than 3.0 %.

Universal Fully Integrated Wearable Sensor Arrays for the Multiple Electrolyte and Metabolite Monitoring in Raw Sweat, Saliva, or Urine

Yanni Bi,Mimi Sun,Jingjuan Wang,Ziyu Zhu,Jing Bai,Mohammed Y. Emran,Ahmed Kotb,Xiangjie Bo,Ming Zhou

Fully integrated wearable sensors are capable of dynamically, directly, and independently tracking biomarkers in raw noninvasive biofluids without any other equipment or accessories by integrating the unique on-body monitoring feature with the special complete functional implementation attribute. Sweat, saliva, and urine are three important noninvasive biofluids, and changes in their biomarkers hold great potential for revealing physiological conditions. However, it is still a challenge to design single fully integrated wearable sensor arrays (FIWSAs) that are universally able to concurrently measure electrolytes and metabolites in three of the most common noninvasive biofluids including sweat, saliva, and urine. Here, we propose the first single universal FIWSAs for wirelessly, noninvasively, and simultaneously measuring various metabolites (i.e., uric acid) and electrolytes (i.e., Na+ and H+) in raw sweat, saliva, or urine under subjects’ exercise by integrating the specifically designed microfluidic, sensing, and electronic modules in a seamless manner. We evaluate its utility for noninvasive gout management in healthy subjects and in gout patients through a purine-rich meal challenge and with a medicine-treatment control, respectively. Noninvasive monitoring of multiple electrolytes and metabolites in a variety of raw noninvasive biofluids via such single universal FIWSAs may enrich the understanding of the biomarkers’ levels in the body and would also facilitate self-health management.

Vertical growth of leaf-like Co-metal organic framework on carbon fiber cloth as integrated electrode for sensitive detection of dopamine and uric acid

Fugang Xu,Liwei Wang,Meijuan Wu,Guangran Ma

Application of metal organic framework (MOF) in electrochemical sensors usually suffer from poor conductivity, low electrocatalysis , material aggregation and complex electrode fabrication. Here, leaf-like Co-MOF ( L -Co-MOF) vertically grown on carbon cloth (CC) was prepared as integrated electrode for electrochemical detection . The L -Co-MOF/CC with interlaced Co-MOF nanosheets as building blocks greatly reduces aggregation, provides large surface area and highly exposed active sites to interact with analyte. The synergy between L -Co-MOF and CC endows the composite greatly enhanced electrocatalysis on oxidation of dopamine (DA) and uric acid (UA) compared with those of ordinary polyhedral Co-MOF or 2D Co-MOF grown in solution. The L -Co-MOF/CC can be directly used as working electrode without further modification, and it achieved the separate detection of DA and UA in the range of 5.6 nM-70 μM, and 21 nM-350 μM, respectively. Simultaneous detection of DA and UA was also performed with a LOD of 2.5 nM for DA and 7 nM for UA, respectively. The sensor with high reproducibility and good anti-interference properties also achieved practical sensing of DA and UA in serum with recoveries of 83.3–104.0%. Such integrated 2D-MOF-carbon material composite with unique structure and high electrocatalysis hold great promise in electrochemical device.

Novel Chemiluminescence Sensing for the Visual Detection of Sarcosine based Upon an Iron-based Metal–Organic Gel with Peroxidase-like Activity

Yuguang Jing,Yue Hu,Yongcheng He,Jiao Yang,Yingchun Li

Preparation of amorphous Ni/Co bimetallic nanoparticles to enhance the electrochemical sensing of glucose

Mengyao Liu,Taotao Gao,Hongmei Li,Bo Xie,Chunqiong Hu,Yong Guo,Dan Xiao

Based on the incidence of diabetes, developing glucose sensors of superior performance with low-cost transition metals (TMs) has been the direction of many researchers, amorphous TMs with highly efficient electrocatalytic properties have attracted our interest. On this basis, amorphous nickel–cobalt bimetallic N -doped carbon nanoparticles on carbon cloth (a-Ni 2 /Co 1 -NC/CC) were fabricated from ZIF-8, which was then used to fabricate an enzyme-free glucose sensor. It was found that the a-Ni 2 /Co 1 -NC/CC had the best response to glucose in 0.4 M NaOH at 0.55 V (vs Hg/HgO). As compared to crystal Ni 2 /Co 1 nanoparticle on carbon cloth (c-Ni 2 /Co 1 NPs/CC), cyclic voltammetry (CV) and chronoamperometry studies revealed that the a-Ni 2 /Co 1 -NC/CC showed a significant increase in the efficient of electrochemical oxidation of glucose under optimal conditions, exhibiting a high sensitivity of 2.455 mA mM −1 cm −2 with a low detection limit of 0.15 μM (S/N = 3). Furthermore, the constructed sensor based on a-Ni 2 /Co 1 -NC/CC also has long-term stability and can be used to detect glucose accurately in beverages (pure milk, coffee drinks, tea drinks, and soda water) with reasonable recovery from 95.6 % to 105.6 %. This study provides a simple and feasible method for the construction of a highly sensitive non-enzyme glucose electrochemical sensor based on amorphous TMs.

Rational design of semiconducting polymer poly[(9,9-dioctylfluorenyl-2,7-diyl)-co-(6-{4-ethyl-piperazin-1-yl}-2-phenyl-benzo{de}isoquinoline-1,3-dione)] for highly selective photoelectrochemical assay of p-phenylenediamine

Kangdi Guan,Ziwei Zhang,Qiang Zhang,Pinghua Ling,Feng Gao

Herein, this paper reports a simple and label-free photoelectrochemical (PEC) sensor based on the organic semiconducting conjugated polymer-polyfluorene derivative, poly[(9,9-dioctylfluorenyl-2,7-diyl)-co-(6-{4-ethyl-piperazin-1-yl}-2-phenyl-benzo{de}isoquinoline-1,3-dione)] (PFNA). The PFNA was designed and obtained the lowest unoccupied molecular orbital (LUMO)/highest occupied molecular orbital (HOMO) values via spectral characterizations. The PFNA modified electrode produced a stable and enhanced photocurrent signal under white light irradiation at a bias of −0.1 V in phosphate buffer solution. A sensitive increment of the photocurrent was observed with the addition of p -phenylenediamine ( p -PD). A possible mechanism for this photoelectrochemical process including the photoexcitation of the polymer, electron injection from polymer toward the electrode, and the hole-scavenging process by the reductants were studied. The π bond in the polymer might facilitate the photoelectrochemical process owing to the enhanced electronic coupling between the polymer and the reductants. A PEC analysis on p -PD has been carried out to evaluate the photoelectrochemical performances of the modified electrode, which presents the wide linear ranges of 0.2–400 μM, with a lower detection limit of 0.13 μM. This work reports the PEC performance of organic semiconducting conjugated polymer-polyfluorene derivative, which would promote more efficient photoelectrochemical design of sensors and devices.

Facile preparation of metal-free graphitic-like carbon nitride/graphene oxide composite for simultaneous determination of uric acid and dopamine

Yonghui Xia,Guangli Li,Yuefang Zhu,Quanguo He,Changping Hu

Graphitic-like carbon nitride/graphene oxide composite nanosheets (g-C 3 N 4 /GO) were synthesized for simultaneous determination of uric acid (UA) and dopamine (DA). The surface features and electrochemical properties of the g-C 3 N 4 /GO were investigated by scanning electron microscopy, X-ray diffraction, cyclic voltammetry and electrochemical impedance spectra. The voltammetric responses of UA and DA were determinated by cyclic voltammetry and differential pulse voltammetry. g-C 3 N 4 /GO had significantly improved electrical conductivity, selective oxidation capacity and electrocatalytic activity. The proposed g-C 3 N 4 /GO modified glassy carbon electrode (GCE) consequently displayed excellent electrocatalytic activity for UA and DA, with a broad linear detection range (0.03–30 μM) and extremely low detection limits (UA 4.6 nM; DA 5.4 nM). The proposed g-C 3 N 4 /GO/GCE also demonstrated excellent reproducibility, selectivity and stability. The levels of UA and DA in human serum were measured by the g-C 3 N 4 /GO/GCE, and then the known concentrations of UA and DA were spiked to the samples, which proved that the recoveries were good.

Construction of a nano dispersed Cr/Fe-polycrystalline sensor via high-energy mechanochemistry for simultaneous electrochemical determination of dopamine and uric acid

Chu Zhe,Gong Wenxue,Muhammad Yaseen,Shah Syed Jalil,Liu Qing,Xing Linguang,Zhou Xueyun,Liu Ying,Zhao Zhenxia,Zhao Zhongxing

A bimetallic polycrystalline sensor (Cr/Fe-SNCM) having nanosized and high dispersion was designed and used for the electrochemical simultaneous determination of dopamine (DA) and uric acid (UA). Catalytic nanosized Cr/Fe were highly anchored on N/S/O-contained porous carbon with high dispersion and polycrystalline Cr/Fe via energetic mechanochemical method and high-temperature carbonization. The obtained Cr/Fe-SNCM exhibited high graphitized carbon supporter and endowed high electron transport and signal output for the whole sensor. Moreover, highly dispersed Cr/Fe sites and the polycrystalline form (metal-N/S/O) efficiently enhanced the catalytic reaction, leading to a limits of detection (based on the 3σ/m criterion) of 25.8 and 22.5 nM for DA and UA, respectively. This is 1–2 orders of magnitude lower than many state-of-the-art reported sensors. The Cr/Fe-SNCM 1.0 sensor exhibited wide working range (0.1 to 10.0 μM), high recovery (96–103%) and low relative standard deviation (RSD = 3.2–4.7%) for DA and UA in real serum samples, possessing high significance for practical large-scale applications. Graphical abstract