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[Display omitted] • Early diagnoses of diseases require us to detection tiny biomarkers. • Nanofluidic devices magnify signal of tiny biomarkers. • Nanofluidic devices hold a promise for in portable sensors and POC detection. Disease diagnosis, especially for early diagnosis, is the most effective method to prevent disease development and mortality. However, low abundance clinical biomarkers in samples pose a challenge to sensitivity and selectivity of early diagnosis. Nanoconfined environment provides unique effects, including ionic current rectification, steric effect, and selective transport, etc., which could be applied to magnify signal and enhance sensitivity in discrimination of biomarkers on electrochemical (EC) sensors. Therefore, nanofluidic EC sensors have experienced a speedy development in ultra-sensitive sensing. In this review, we highlight the application of nanofluidic EC sensors with different structures (nanocapillary, nanoporous membrane, nanopore, and micro/nanofluidic chip) in biomarkers detection. Different types of nanofluidic devices, mechanism of nanoconfined effect, and their applications in ultra-sensitive sensing are summarized and discussed. Finally, this review provides a respective about nanofluidic EC sensors in biomarkers detection and helps the understanding nanoconfined effect for developing new analysis. [ABSTRACT FROM AUTHOR]

A general and efficient catalytic system for Pd 2 (dba) 3 -catalyzed ligand-free Suzuki cross-coupling reactions was developed. The cross-couplings of a wide range of aryl halides with various arylboronic acids were feasible under mild conditions in environmental friendly [hmim]NTf 2 /supercritical CO 2 biphasic system employing K 2 CO 3 as a base, which provided in good to high yields to the corresponding products. The catalytic system could be recycled and reused without significant loss of catalytic activity. Additionally, a possible mechanism of the Suzuki cross-coupling reaction is depicted in this paper. [ABSTRACT FROM AUTHOR]

Abstract: A simple, mild, and efficient procedure for the oxidation of organic halides to aldehydes and ketones with H5IO6 in ionic liquid [C12mim][FeCl4] has been developed. The oxidation reactions afford the target products in good to high yields and no overoxidation was observed. The products can be separated by a simple extraction with organic solvent, and the catalytic system can be recycled and reused without loss of catalytic activity. [Copyright &y& Elsevier]

Abstract: The effect of surface microstructures of microchannels on the separation efficiency in microchip electrophoresis has been studied. In order to understand the influence of the surface microstructures on the microchip electrophoresis performance, a thermostatic system was designed and fabricated for precisely control of the chip temperature since the surrounding temperature causes a significant effect on the separation efficiency. The periodically ordered microstructures (dams) of different sizes were fabricated on the microchannels by a simple printing process using different gray levels of the vector graphic software. And the influence of dam sizes in microchannels on the separation efficiency was evaluated by using the number of theoretical plates (N) and the relative resolution (Rs’). Analyzing the variations of mixing elements caused by the periodically ordered dams in the separate channel and elution time, we found that with small dam size fabricated at low gray level of ca. 30%, the resolution of dopamine and epinephrine increased slightly, while it decreased obviously with larger dam sizes especially fabricated at gray level of 50%. [Copyright &y& Elsevier]

Abstract: The Ag/MgO(001) system has been studied by first-principle method based on density function theory, adsorption of Ag n (n =1–5) clusters on MgO(001) surface have been investigated to elucidate the initial stage of Ag atom deposition on MgO surface. It was found that the preferential adsorption site for an isolated Ag atom is directly above the surface oxygen atom and a weak bond is formed. Various structural configurations have been examined for the Ag n clusters and standing planar structures were found to be energetically more stable than flat planar structures. Energy and electronic properties revealed that with the increase of Ag coverage, the interaction of adsorbate–adsorbate bonds prevails over adsorbate–substrate bonds, leading to a Volmer–Weber mode deposition. [Copyright &y& Elsevier]

Abstract: Although most of enzyme catalytic reactions are specific, the amperometric detection of the enzymatic reaction products is largely nonselective. How to improve the detection selectivity of the enzyme-based electrochemical biosensors has to be considered in the sensor fabrication procedures. Herein, a highly selective amperometric glucose biosensor based on the concept of diffusion layer gap electrode pair which we previously proposed was designed. In this biosensor, a gold tube coated with a conductive layer of glucose oxidase/Nafion/graphite was used to create an interference-free region in its diffusion layer by electrochemically oxidizing the interfering electroactive species at proper potentials. A Pt probe electrode was located in this diffusion layer of the tube electrode to selectively detect hydrogen peroxide generated from the enzyme catalytic oxidation of glucose in the presence of oxygen in the solution. In practical performance of the microdevice, parameters influencing the interference-removing efficiency, including the tip-tube opening distance, the tube electrode potential and the electrolyzing time had been investigated systematically. Results showed that glucose detection free from interferents could be achieved at the electrolyzing time of 30s, the tip-tube opening distance of 3mm and the tube electrode potential of 0.4V. The electrochemical response showed linear dependence on the concentration of glucose in the range of 1×10−5 to 4×10−3 M (the correlation coefficient: 0.9936, without interferents; 0.9995, with interferents). In addition, the effectiveness of this device was confirmed by numerical simulation using a model system of a solution containing interferents. The simulated results showed good agreement with the experimental data. [Copyright &y& Elsevier]

Abstract: Generally speaking, measurement of hydroxylated radical products of salicylic acid requires a fussy separation process. In this study, we describe a simple method to electrochemically detect hydroxyl radicals ( 4-hydroxybenzoic acid (4-HBA) as the The erated by the Fenton reaction from iron (II) sulfate and hydrogen peroxide in a phosphate buffer solution. Experimental results show that our method can detect the igh sensitivity without any separation process. The differential pulse voltammetric responses show a linear dependence on the concentration of ange of 2.0×10−6 and 1.0×10−3 M with a determination limit down to 5.0×10−7 M. As a demonstration, the kinetics of the Fenton reaction was mapped by measuring the reaction product of hydroxyl radical trapped by 4-HBA. The result is in good agreement with that reported previously. All the results show that the present approach could provide a simple, inexpensive and promising method for biomedicine and iatrology. [Copyright &y& Elsevier]

Abstract: We describe a novel photochemical method to synthesize compacted Prussian blue (PB) film from an acidic ferricyanide solution. The key step is the photochemical reduction of ferricyanide ion to ferrocyanide ion that subsequently coordinates with the free ferric ion dissociated from the ferricyanide in acidic medium to form Prussian blue on the illuminated electrode surface. The prepared PB film electrode shows high electrocatalytic activity towards the reduction of hydrogen peroxide and the amperometric responses show a linear dependence on the concentration of hydrogen peroxide in a range of 1.0×10−6 to 1.2×10−3 M with a detection limit down to 4×10−7 M. The present photochemical method provides a simple and promising route for the local fabrication of patterned molecular magnets, ion-selective sensors, and electro- or photochromic devices. [Copyright &y& Elsevier]

Abstract: An efficient method for the selective hydration of nitrile to amide by employing inexpensive copper salt catalyst and commercially available acetaldoxime in environmentally friendly water is described. Under this protocol, nitriles including aromatic nitriles, heterocyclic nitriles and aliphatic nitriles were converted into the corresponding amides in good to excellent yields. [Copyright &y& Elsevier]

Abstract: The structural distortion of -structured MnO and FeO under high pressure is investigated using ab initio methods within GGA and GGA+U approximations. Present calculations indicated that the ordinary density-functional calculation overestimated the structural distortion of MnO and FeO under pressure. When the strong electronic correlations are included in the form of GGA+U, a reasonable description of the structural distortion under high pressure can be obtained. The overestimation of exchange interactions in ordinary DFT calculations may be the most important reason for the overestimation of structural distortion. [Copyright &y& Elsevier]

Abstract: Rapid separation and determination of acetaminophen and its hydrolysate with end-channel electrochemical (EC) detection integrated on a plastified poly(ethylene terephthalate) (PET)-toner microchip capillary electrophoresis (CE) system was investigated. In this separation and detection system, a Pt ultramicroelectrode integrated on a three-dimensional adjustor was used as working electrode. Factors influencing the separation and detection were investigated and optimized. Results show that acetaminophen and p-aminophenol can be well separated within 84s with R.S.D.<1% for migration time and R.S.D.<3.6% for detection current for both analytes. Detection limits for both analytes are determined to be 5.0μM (S/N=3). This method has been successfully applied to the detection of trace p-aminophenol in paracetamol tablets. The results demonstrate that the PET-toner microchips can obtain better performance than PDMS microfluidic devices but at much lower cost. [Copyright &y& Elsevier]

A series of MCM-41 supported functionalized ionic liquids doped with copper species were prepared, characterized and evaluated as catalysts in the Biginelli reaction. Most of these supported ionic liquids perform well in the reaction, especially the multifunctional copper coordinated MCM-41 supported heterogeneous catalysts (0.5)IL-TiCl 5 @MCM-41@Cu(15) and (0.5)IL-HSO 4 @MCM-41@Cu(15). The catalytic tests revealed that (0.5)IL-HSO 4 @MCM-41@Cu(15) was the best and powerful catalyst in the Biginelli reaction for the preparation of 3,4-dihydropyrimidinones with high to excellent yields. The catalyst can be easily separated from the reaction mixture by filtration and reused in six consecutive cycles without significant loss in catalytic activity. [ABSTRACT FROM AUTHOR]

Abstract: The use of single chemotherapeutic drug has shown some limitations in anti-tumor treatment, such as development of drug resistance, high toxicity and limited regime of clinical uses. The combination of two or more therapeutic drugs is feasible means to overcome the limitations. Co-delivery strategy has been proposed to minimize the amount of each drug and to achieve the synergistic effect for cancer therapies. Attempts have been made to deliver chemotherapeutic drugs simultaneously using drug carriers, such as micelles, liposomes, and inorganic nanoparticles (NPs). Here we reported core-shell NPs that were doubly emulsified from an amphiphilic copolymer methoxy poly(ethylene glycol)-poly(lactide-co-glycolide) (mPEG-PLGA). These NPs offered advantages over other nanocarriers, as they were easy to fabricate by improved double emulsion method, biocompatible, and showed high loading efficacy. More importantly, these NPs could co-deliver hydrophilic doxorubicin (DOX) and hydrophobic paclitaxel (TAX). The drug-loaded NPs possessed a better polydispersity, indicating that they are more readily subject to controlled size distribution. Studies on drug release and cellular uptake of the co-delivery system demonstrated that both drugs were effectively taken up by the cells and released simultaneously. Furthermore, the co-delivery nanocarrier suppressed tumor cells growth more efficiently than the delivery of either DOX or TAX at the same concentrations, indicating a synergistic effect. Moreover, the NPs loading drugs with a DOX/TAX concentration ratio of 2:1 showed the highest anti-tumor activity to three different types of tumor cells. This nanocarrier might have important potential in clinical implications for co-delivery of multiple anti-tumor drugs with different properties. [Copyright &y& Elsevier]

Abstract: Separation and determination of dopamine and epinephrine with end-channel electrochemical (EC) detection integrated on a native printed microchip capillary electrophoresis (CE) system was investigated. Factors influencing the separation and detection were investigated and optimized. Results show manipulating EOF, which can be easily achieved by adjusting buffer pH, is a simple and effective way to achieve the baseline separation of dopamine and epinephrine in native polymeric microchips. Without surface modification of microchannel, printed microchips with advantages of low cost and easy preparation can achieve high performance like other microfluidic devices. [Copyright &y& Elsevier]