The journal of physical chemistry. A, Jan 27, 2015
Our previous research has demonstrated that using ethanol-water mixture as a liquid medium for th... more Our previous research has demonstrated that using ethanol-water mixture as a liquid medium for the synthesis of gold nanoparticles (AuNPs) by the solution plasma process (SPP) could lead to an increment of the reaction rate of ~15 times faster than that in pure water. This drastic change was observed when a small amount of ethanol, i.e. at an ethanol mole fraction (xethanol) of 0.089, was added in the system. After this composition, the reaction rate decreased continuously. To better understand what happens in the ethanol-water mixtures based SPP, in this study, effect of the ethanol content on the radical formation in the system was verified. We focused on detecting the magnetic resonance of electronic spins using electron spin resonance (ESR) spectroscopy to determine the type and quantity of the generated radicals at each xethanol. Results indicated that ethanol radicals was generated in the ethanol-water mixtures and exhibited maximum quantity at the xethanol of 0.089. This cond...
Physical chemistry chemical physics : PCCP, Jan 3, 2015
An extraordinary high-speed synthesis of gold nanoparticles (AuNPs) was discovered by synthesizin... more An extraordinary high-speed synthesis of gold nanoparticles (AuNPs) was discovered by synthesizing the AuNPs in ethanol-water mixtures using a solution plasma process (SPP). The influence of the ethanol mole fraction (χethanol) in the ethanol-water mixtures on the reduction rate of gold chloride ions to AuNPs under the SPP system was studied. The results indicated that the reaction rate of the AuNPs synthesis exhibited a maximum value (i.e. 35.2 times faster than in a pure water system) at the significant point where the partial molar volumes of ethanol and water changed drastically.
The extraction of DNA is the most crucial method used in molecular biology. Up to date silica mat... more The extraction of DNA is the most crucial method used in molecular biology. Up to date silica matrices has been widely applied as solid support for selective DNA adsorption and extraction. However, since adsorption force of SiOH functional groups is much greater than that of desorption force, the DNA extraction efficiency of silica surfaces is limited. In order to increase the DNA extraction yield, a new surface with different functional groups which possess of greater desorption property is required. In this study, we proposed cellulose/graphite oxide (GO) composite as an alternative material for DNA adsorption and extraction. GO/Cellulose composite provides the major adsorption and desorption of DNA by COH, which belongs to alkyl or phenol type of OH functional group. Compared to SiOH, COH is less polarized and reactive, therefore the composite might provide a higher desorption of DNA during the elution process. The GO/cellulose composite were prepared in spherical structure by mixing urea, cellulose, NaOH, Graphite oxide and water. The concentration of GO within the composites were controlled to be 0-4.15wt.%. The extraction yield of DNA increased with increasing weight percentage of GO. The highest yield was achieved at 4.15wt.% GO, where the extraction efficiency was reported as 660.4ng/μl when applying 2M GuHCl as the binding buffer. The absorbance ratios between 260nm and 280nm (A260/A280) of the DNA elution was demonstrated as 1.86, indicating the extracted DNA consisted of high purity. The results proved that GO/cellulose composite provides a simple method for selective DNA extraction with high extraction efficiency of pure DNA.
Metal-free nitrogen-doped carbon materials are currently considered at the forefront of potential... more Metal-free nitrogen-doped carbon materials are currently considered at the forefront of potential alternative cathode catalysts for the oxygen reduction reaction (ORR) in fuel cell technology. Despite numerous efforts in this area over the past decade, rational design and development of a new catalyst system based on nitrogen-doped carbon materials via an innovative approach still present intriguing challenges in ORR catalysis research. Herein, a new kind of nitrogen-doped carbon nanoparticle-carbon nanofiber (NCNP-CNF) composite with highly efficient and stable ORR catalytic activity has been developed via a new approach assisted by a solution plasma process. The integration of NCNPs and CNFs by the solution plasma process can lead to a unique morphological feature and modify physicochemical properties. The NCNP-CNF composite exhibits a significantly enhanced ORR activity through a dominant four-electron pathway in an alkaline solution. The enhancement in ORR activity of NCNP-CNF c...
ABSTRACT Electrical discharges in water offer a unique plasma source which can be utilized in var... more ABSTRACT Electrical discharges in water offer a unique plasma source which can be utilized in various novel applications. These discharges are distinguished for the rapid in situ production of highly reactive species when high voltage of about 10-20 kV is applied. Images of the plasma discharges in the water, which are generated by using high-frequency bipolar pulse power supply at relatively low ignition voltages, are presented here.
Zinc oxide (ZnO) was successfully synthesized by applying a solution plasma, a plasma discharge i... more Zinc oxide (ZnO) was successfully synthesized by applying a solution plasma, a plasma discharge in a liquid phase, without the addition of a reducing agent and simultaneously deposited into a bacterial cellulose pellicle that functioned as a template. By the reasons of its nano-sized structure as well as favorable porous configuration, the BC pellicle has been proved to be a splendid upholding template for the coordination of ZnO. In addition, the ZnO-deposited BC composites demonstrated strong antibacterial activity without a photocatalytic reaction against both Staphylococcus aureus and Escherichia coli. Hence, the ZnO-deposited BC composites can be used as an antibacterial material in wound dressing and water disinfection applications.
ABSTRACT Herein, it is reported that a novel in-situ one-step synthesis method of bimetallic nano... more ABSTRACT Herein, it is reported that a novel in-situ one-step synthesis method of bimetallic nanoparticles (NPs) supported on carbon blacks, which can markedly prevent the aggregation and growth of NPs, resulting in a small particle size (average 5 nm), good dispersion, and high-electrocatalytic-activity.
Small-sized and well-dispersed gold nanoparticles (NPs) for nanofluidics have been synthesized by... more Small-sized and well-dispersed gold nanoparticles (NPs) for nanofluidics have been synthesized by electrical discharge in liquid environment using termed solution plasma processing (SPP). Electrons and the hydrogen radicals are reducing the gold ions to the neutral form in plasma gas phase and liquid phase, respectively. The gold NPs have the smallest diameter of 4.9 nm when the solution temperature was kept at 20 °C. Nucleation and growth theory describe the evolution of the NP diameter right after the reduction reaction in function of the system temperature, NP surface energy, dispersion energy barrier, and nucleation rate. Negative charges on the NPs surface during and after SPP generate repulsive forces among the NPs avoiding their agglomeration in solution. Increasing the average energy in the SPP determines a decrease of the zeta potential and an increase of the NPs diameter. An important enhancement of the thermal conductivity of 9.4% was measured for the synthesized nanofluids containing NPs with the smallest size.
Journal of the Taiwan Institute of Chemical Engineers, 2014
ABSTRACT Gold nanoparticles (AuNPs) stabilized in alginate matrix were synthesized by applying th... more ABSTRACT Gold nanoparticles (AuNPs) stabilized in alginate matrix were synthesized by applying the plasma into alginate aqueous solution containing gold(III) chloride trihydrate precursor. Effect of the solution plasma process (SPP) discharge time on the physical properties, including shape and size, and the optical absorption properties of the synthesized AuNPs were investigated by varying the discharge times to be 0, 5, 10, 20 and 30 min. Results reveal that the increase in the discharge time leads to a size reduction of the AuNPs. Also, the particles tend to be more spherical. Appearance of the obtained AuNPs-alginate suspensions along with the change in their UV–vis absorption spectra intensity after samples were left standing for several time intervals suggest that alginate solution itself can act both as a stabilizer and a reducing agent for the AuNPs formation while the application of plasma helps to improve the controllability of shape and size of the synthesized particles. Furthermore, the method is simple, reproducible, and does not need any manipulative skill. Since the reducing agent is not required, the method is suitable for utilizing in biomedical application.
The journal of physical chemistry. A, Jan 27, 2015
Our previous research has demonstrated that using ethanol-water mixture as a liquid medium for th... more Our previous research has demonstrated that using ethanol-water mixture as a liquid medium for the synthesis of gold nanoparticles (AuNPs) by the solution plasma process (SPP) could lead to an increment of the reaction rate of ~15 times faster than that in pure water. This drastic change was observed when a small amount of ethanol, i.e. at an ethanol mole fraction (xethanol) of 0.089, was added in the system. After this composition, the reaction rate decreased continuously. To better understand what happens in the ethanol-water mixtures based SPP, in this study, effect of the ethanol content on the radical formation in the system was verified. We focused on detecting the magnetic resonance of electronic spins using electron spin resonance (ESR) spectroscopy to determine the type and quantity of the generated radicals at each xethanol. Results indicated that ethanol radicals was generated in the ethanol-water mixtures and exhibited maximum quantity at the xethanol of 0.089. This cond...
Physical chemistry chemical physics : PCCP, Jan 3, 2015
An extraordinary high-speed synthesis of gold nanoparticles (AuNPs) was discovered by synthesizin... more An extraordinary high-speed synthesis of gold nanoparticles (AuNPs) was discovered by synthesizing the AuNPs in ethanol-water mixtures using a solution plasma process (SPP). The influence of the ethanol mole fraction (χethanol) in the ethanol-water mixtures on the reduction rate of gold chloride ions to AuNPs under the SPP system was studied. The results indicated that the reaction rate of the AuNPs synthesis exhibited a maximum value (i.e. 35.2 times faster than in a pure water system) at the significant point where the partial molar volumes of ethanol and water changed drastically.
The extraction of DNA is the most crucial method used in molecular biology. Up to date silica mat... more The extraction of DNA is the most crucial method used in molecular biology. Up to date silica matrices has been widely applied as solid support for selective DNA adsorption and extraction. However, since adsorption force of SiOH functional groups is much greater than that of desorption force, the DNA extraction efficiency of silica surfaces is limited. In order to increase the DNA extraction yield, a new surface with different functional groups which possess of greater desorption property is required. In this study, we proposed cellulose/graphite oxide (GO) composite as an alternative material for DNA adsorption and extraction. GO/Cellulose composite provides the major adsorption and desorption of DNA by COH, which belongs to alkyl or phenol type of OH functional group. Compared to SiOH, COH is less polarized and reactive, therefore the composite might provide a higher desorption of DNA during the elution process. The GO/cellulose composite were prepared in spherical structure by mixing urea, cellulose, NaOH, Graphite oxide and water. The concentration of GO within the composites were controlled to be 0-4.15wt.%. The extraction yield of DNA increased with increasing weight percentage of GO. The highest yield was achieved at 4.15wt.% GO, where the extraction efficiency was reported as 660.4ng/μl when applying 2M GuHCl as the binding buffer. The absorbance ratios between 260nm and 280nm (A260/A280) of the DNA elution was demonstrated as 1.86, indicating the extracted DNA consisted of high purity. The results proved that GO/cellulose composite provides a simple method for selective DNA extraction with high extraction efficiency of pure DNA.
Metal-free nitrogen-doped carbon materials are currently considered at the forefront of potential... more Metal-free nitrogen-doped carbon materials are currently considered at the forefront of potential alternative cathode catalysts for the oxygen reduction reaction (ORR) in fuel cell technology. Despite numerous efforts in this area over the past decade, rational design and development of a new catalyst system based on nitrogen-doped carbon materials via an innovative approach still present intriguing challenges in ORR catalysis research. Herein, a new kind of nitrogen-doped carbon nanoparticle-carbon nanofiber (NCNP-CNF) composite with highly efficient and stable ORR catalytic activity has been developed via a new approach assisted by a solution plasma process. The integration of NCNPs and CNFs by the solution plasma process can lead to a unique morphological feature and modify physicochemical properties. The NCNP-CNF composite exhibits a significantly enhanced ORR activity through a dominant four-electron pathway in an alkaline solution. The enhancement in ORR activity of NCNP-CNF c...
ABSTRACT Electrical discharges in water offer a unique plasma source which can be utilized in var... more ABSTRACT Electrical discharges in water offer a unique plasma source which can be utilized in various novel applications. These discharges are distinguished for the rapid in situ production of highly reactive species when high voltage of about 10-20 kV is applied. Images of the plasma discharges in the water, which are generated by using high-frequency bipolar pulse power supply at relatively low ignition voltages, are presented here.
Zinc oxide (ZnO) was successfully synthesized by applying a solution plasma, a plasma discharge i... more Zinc oxide (ZnO) was successfully synthesized by applying a solution plasma, a plasma discharge in a liquid phase, without the addition of a reducing agent and simultaneously deposited into a bacterial cellulose pellicle that functioned as a template. By the reasons of its nano-sized structure as well as favorable porous configuration, the BC pellicle has been proved to be a splendid upholding template for the coordination of ZnO. In addition, the ZnO-deposited BC composites demonstrated strong antibacterial activity without a photocatalytic reaction against both Staphylococcus aureus and Escherichia coli. Hence, the ZnO-deposited BC composites can be used as an antibacterial material in wound dressing and water disinfection applications.
ABSTRACT Herein, it is reported that a novel in-situ one-step synthesis method of bimetallic nano... more ABSTRACT Herein, it is reported that a novel in-situ one-step synthesis method of bimetallic nanoparticles (NPs) supported on carbon blacks, which can markedly prevent the aggregation and growth of NPs, resulting in a small particle size (average 5 nm), good dispersion, and high-electrocatalytic-activity.
Small-sized and well-dispersed gold nanoparticles (NPs) for nanofluidics have been synthesized by... more Small-sized and well-dispersed gold nanoparticles (NPs) for nanofluidics have been synthesized by electrical discharge in liquid environment using termed solution plasma processing (SPP). Electrons and the hydrogen radicals are reducing the gold ions to the neutral form in plasma gas phase and liquid phase, respectively. The gold NPs have the smallest diameter of 4.9 nm when the solution temperature was kept at 20 °C. Nucleation and growth theory describe the evolution of the NP diameter right after the reduction reaction in function of the system temperature, NP surface energy, dispersion energy barrier, and nucleation rate. Negative charges on the NPs surface during and after SPP generate repulsive forces among the NPs avoiding their agglomeration in solution. Increasing the average energy in the SPP determines a decrease of the zeta potential and an increase of the NPs diameter. An important enhancement of the thermal conductivity of 9.4% was measured for the synthesized nanofluids containing NPs with the smallest size.
Journal of the Taiwan Institute of Chemical Engineers, 2014
ABSTRACT Gold nanoparticles (AuNPs) stabilized in alginate matrix were synthesized by applying th... more ABSTRACT Gold nanoparticles (AuNPs) stabilized in alginate matrix were synthesized by applying the plasma into alginate aqueous solution containing gold(III) chloride trihydrate precursor. Effect of the solution plasma process (SPP) discharge time on the physical properties, including shape and size, and the optical absorption properties of the synthesized AuNPs were investigated by varying the discharge times to be 0, 5, 10, 20 and 30 min. Results reveal that the increase in the discharge time leads to a size reduction of the AuNPs. Also, the particles tend to be more spherical. Appearance of the obtained AuNPs-alginate suspensions along with the change in their UV–vis absorption spectra intensity after samples were left standing for several time intervals suggest that alginate solution itself can act both as a stabilizer and a reducing agent for the AuNPs formation while the application of plasma helps to improve the controllability of shape and size of the synthesized particles. Furthermore, the method is simple, reproducible, and does not need any manipulative skill. Since the reducing agent is not required, the method is suitable for utilizing in biomedical application.
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