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2012 Volume 29 Issue 5
2012, 29(5): 489-497
doi: 10.3724/SP.J.1095.2012.00328
Abstract:
The research progress of superhydrophobic bio-surfaces of some insects including moth,cicada,butterfly,termite,stenocara,mosquito,water strider and lotus leaves was introduced.Preparation methods and common materials used for constructing biomimetic superhydrophobic surfaces were also summarized.Finally the challenges and the latest development trends in the study of superhydrophobic materials were discussed.
The research progress of superhydrophobic bio-surfaces of some insects including moth,cicada,butterfly,termite,stenocara,mosquito,water strider and lotus leaves was introduced.Preparation methods and common materials used for constructing biomimetic superhydrophobic surfaces were also summarized.Finally the challenges and the latest development trends in the study of superhydrophobic materials were discussed.
2012, 29(5): 498-503
doi: 10.3724/SP.J.1095.2012.00273
Abstract:
n0.5G~5.0G dendrimers with ethylene diamine as core were synthesized from alternating copolymeraziation of methacrylate by Michael addition reaction.The structures of all products were characterized by FTIR,1H NMR,HPLC,and elemental analysis.The influences of the reaction temperature,reaction time and ratio of reactants were investigated.The reaction temperature is 25℃ for the half-generations and 35℃ for the full-generations.The optimum reaction time is 18 h for 0.5G,24 h for 1.0G and 1.5G,36 h for 2.0G and 2.5G,48 h for 3.0G and 3.5G,3 d for 4.0 and 4.5G,and 4 d for 5.0G.The main difficulty in the synthesis is the separation and purification of the products.The results showed that the purity of polyamidoamine dendrimers was improved by solvent extraction using ether as extractant and ethanol as exchanged solvent.
n0.5G~5.0G dendrimers with ethylene diamine as core were synthesized from alternating copolymeraziation of methacrylate by Michael addition reaction.The structures of all products were characterized by FTIR,1H NMR,HPLC,and elemental analysis.The influences of the reaction temperature,reaction time and ratio of reactants were investigated.The reaction temperature is 25℃ for the half-generations and 35℃ for the full-generations.The optimum reaction time is 18 h for 0.5G,24 h for 1.0G and 1.5G,36 h for 2.0G and 2.5G,48 h for 3.0G and 3.5G,3 d for 4.0 and 4.5G,and 4 d for 5.0G.The main difficulty in the synthesis is the separation and purification of the products.The results showed that the purity of polyamidoamine dendrimers was improved by solvent extraction using ether as extractant and ethanol as exchanged solvent.
2012, 29(5): 504-509
doi: 10.3724/SP.J.1095.2012.00200
Abstract:
Polyaniline doped with an organic phosphate(PANI-OP) was blended with water-borne epoxy resin and used as an anti-corrosion material.The long-term anti-corrosion behavior of the material was investigated.Transmission electron microscopy showed that the PANI-OP powder was uniformly dispersed in the waterborne epoxy resin when the PANI content was below 1%.The diameter of the particle decreased to ca.50~100 nm when the PANI content was 0.1%.Electrochemical impedance spectroscopy and the changes in open circuit potential indicated that the presence of polyaniline coating significantly improved the anti-corrosion effect.X-rays photoelectron spectra showed that a dense passive film of iron oxide(FeO and Fe2O3) on the surface was accounted for the anti-corrosion;in the meanwhile,the presence of P indicated that the dopant ion was also involved in the corrosion protection process.
Polyaniline doped with an organic phosphate(PANI-OP) was blended with water-borne epoxy resin and used as an anti-corrosion material.The long-term anti-corrosion behavior of the material was investigated.Transmission electron microscopy showed that the PANI-OP powder was uniformly dispersed in the waterborne epoxy resin when the PANI content was below 1%.The diameter of the particle decreased to ca.50~100 nm when the PANI content was 0.1%.Electrochemical impedance spectroscopy and the changes in open circuit potential indicated that the presence of polyaniline coating significantly improved the anti-corrosion effect.X-rays photoelectron spectra showed that a dense passive film of iron oxide(FeO and Fe2O3) on the surface was accounted for the anti-corrosion;in the meanwhile,the presence of P indicated that the dopant ion was also involved in the corrosion protection process.
2012, 29(5): 510-514
doi: 10.3724/SP.J.1095.2012.00281
Abstract:
Two oxoisoaporphine-melatonin hybrids(compound 2a and 2b) have been designed,synthesized and tested for their ability to inhibit acetylcholinesterase,butyrylcholinesterase,acetylcholinesterase-induced β-amyloid(Aβ) aggregation.Their inhibitory mechanism and antioxidant properties were also studied.The synthetic compounds(2a and 2b) exhibited moderate AChE inhibitory activity with IC50 values in the micromolar range in most cases.Non-competitive binding mode was found for these derivatives.Moreover,the compounds(2a and 2b) exhibit high acetylcholinesterase-induced Aβ antiaggregating activity with inhibitory potencies ranging from 79.3% to 84.7%,and significant antioxidant properties with peroxyl radical absorbance capacities ranging from 1.1-to 1.5-fold the value of trolox.
Two oxoisoaporphine-melatonin hybrids(compound 2a and 2b) have been designed,synthesized and tested for their ability to inhibit acetylcholinesterase,butyrylcholinesterase,acetylcholinesterase-induced β-amyloid(Aβ) aggregation.Their inhibitory mechanism and antioxidant properties were also studied.The synthetic compounds(2a and 2b) exhibited moderate AChE inhibitory activity with IC50 values in the micromolar range in most cases.Non-competitive binding mode was found for these derivatives.Moreover,the compounds(2a and 2b) exhibit high acetylcholinesterase-induced Aβ antiaggregating activity with inhibitory potencies ranging from 79.3% to 84.7%,and significant antioxidant properties with peroxyl radical absorbance capacities ranging from 1.1-to 1.5-fold the value of trolox.
2012, 29(5): 515-519
doi: 10.3724/SP.J.1095.2012.00201
Abstract:
(1-(4-Vinylbenzyl)-1H-1,2,3-triazol-4-yl)methanol(VBTM) monomer was synthesized via click chemistry and RAFT polymerization method was utilized to achieve 1,2,3-triazole-functionalized diblock copolymer(PS-b-PVBTM).The diblock copolymer was spin-coated on gold substrate to form a thin film consisted of nano-spherical structures with enriched PS as core and PVBTM as corona.After being annealed at 90℃ for 24 h,the spherical structure was changed to donut-like nano-structure with PS enriched on the surface.Adsorption of proteins on the spin-coated thin film was studied by surface plasma reasonance.The film could absorb bovine serum albumin(BSA) in an acid buffer solution and the absorption capacity was increased as pH decreased while it did not adsorb BSA and myoglobin in a neutral buffer solution.The film adsorbed lysozyme with a pI of 11.0,and the adsorption capacity was weakened by 0.26 ng/mm2 after being annealed.The electrostatic interaction was supposed to be the governing role of adsorption.
(1-(4-Vinylbenzyl)-1H-1,2,3-triazol-4-yl)methanol(VBTM) monomer was synthesized via click chemistry and RAFT polymerization method was utilized to achieve 1,2,3-triazole-functionalized diblock copolymer(PS-b-PVBTM).The diblock copolymer was spin-coated on gold substrate to form a thin film consisted of nano-spherical structures with enriched PS as core and PVBTM as corona.After being annealed at 90℃ for 24 h,the spherical structure was changed to donut-like nano-structure with PS enriched on the surface.Adsorption of proteins on the spin-coated thin film was studied by surface plasma reasonance.The film could absorb bovine serum albumin(BSA) in an acid buffer solution and the absorption capacity was increased as pH decreased while it did not adsorb BSA and myoglobin in a neutral buffer solution.The film adsorbed lysozyme with a pI of 11.0,and the adsorption capacity was weakened by 0.26 ng/mm2 after being annealed.The electrostatic interaction was supposed to be the governing role of adsorption.
2012, 29(5): 520-526
doi: 10.3724/SP.J.1095.2012.00300
Abstract:
Di-n-buyltin di-o-chlorobenzoate {[n-Bu2Sn(O2CC10H9)]2O}2 was synthesized by a microwave assisted solid-state synthesis.Its structure has been determined by X-ray single crystal diffraction.The crystal belongs to the triclinic space group P1 with a=1.17653(4) nm,b=1.20672(4) nm,c=2.74090(9) nm,α=80.493(2)°,β=83.995(2)°,γ=64.260(2)°,V=3.4547(2) nm3,Z=2,Dc=1.525 g/cm3,μ(MoKα)=16.34 cm-1,F(000)=1 592,R1=0.0414,wR2=0.1349.In the complex,the tin atoms are five-coordinated in a distorted tigonal bipyram idalstructure,and the dimeric structure constitutes a Sn2O2 planar.Theoretical study on the title complex has been performed using a quantum chemistry calculation by means of G98W package and taking LANL2DZ basis set.The stabilities of the complex,the orbital energies and composition characteristics of some frontier molecular orbitals were presented.
Di-n-buyltin di-o-chlorobenzoate {[n-Bu2Sn(O2CC10H9)]2O}2 was synthesized by a microwave assisted solid-state synthesis.Its structure has been determined by X-ray single crystal diffraction.The crystal belongs to the triclinic space group P1 with a=1.17653(4) nm,b=1.20672(4) nm,c=2.74090(9) nm,α=80.493(2)°,β=83.995(2)°,γ=64.260(2)°,V=3.4547(2) nm3,Z=2,Dc=1.525 g/cm3,μ(MoKα)=16.34 cm-1,F(000)=1 592,R1=0.0414,wR2=0.1349.In the complex,the tin atoms are five-coordinated in a distorted tigonal bipyram idalstructure,and the dimeric structure constitutes a Sn2O2 planar.Theoretical study on the title complex has been performed using a quantum chemistry calculation by means of G98W package and taking LANL2DZ basis set.The stabilities of the complex,the orbital energies and composition characteristics of some frontier molecular orbitals were presented.
2012, 29(5): 527-531
doi: 10.3724/SP.J.1095.2012.00252
Abstract:
Glutamic acid(Glu for short)/magnesium-aluminum layered double hydroxide compounds(Mg-Al-LDH) were prepared in weak acidic medium,and the influence of pH values on the properties of Glu/LDH compounds was investigated.It was found that Glu/LDH particles prepared in weak acidic medium were sphere-like with smaller size compared with that of traditional ion-exchange method.Our study also indicated that the variation of pH value could change the morphology and dispersion state of Glu/LDH particles.The reaction mechanism is discussed.
Glutamic acid(Glu for short)/magnesium-aluminum layered double hydroxide compounds(Mg-Al-LDH) were prepared in weak acidic medium,and the influence of pH values on the properties of Glu/LDH compounds was investigated.It was found that Glu/LDH particles prepared in weak acidic medium were sphere-like with smaller size compared with that of traditional ion-exchange method.Our study also indicated that the variation of pH value could change the morphology and dispersion state of Glu/LDH particles.The reaction mechanism is discussed.
2012, 29(5): 532-536
doi: 10.3724/SP.J.1095.2012.00266
Abstract:
Glycoside acid salt was prepared by selective oxidation from methyl glucoside with 2,2,6,6-tetramethylpiperidinyloxy(TEMPO)/Ca(ClO)2 system.Glucuronic acid and by-products calcium sulfate were obtained by following-up acidification and hydrolization with 2 mol/L H2SO4.The effects of catalytic oxidation conditions on the yield of glucuronic acid were studied.The reaction process was monitored by measuring the pH value of reaction system,the intermediate and products were determined by UV and HPLC.The results showed that the TEMPO/Ca(ClO)2 system had high activity and good selectivity for the catalytic oxidation of glycoside with a 92% yield of glucuronic acid,and Ca2+ ion in the reaction system can be easily removed.Comparing to traditional technology of HNO3 oxidation,this process is more environmental-friendly and conserves more resources.
Glycoside acid salt was prepared by selective oxidation from methyl glucoside with 2,2,6,6-tetramethylpiperidinyloxy(TEMPO)/Ca(ClO)2 system.Glucuronic acid and by-products calcium sulfate were obtained by following-up acidification and hydrolization with 2 mol/L H2SO4.The effects of catalytic oxidation conditions on the yield of glucuronic acid were studied.The reaction process was monitored by measuring the pH value of reaction system,the intermediate and products were determined by UV and HPLC.The results showed that the TEMPO/Ca(ClO)2 system had high activity and good selectivity for the catalytic oxidation of glycoside with a 92% yield of glucuronic acid,and Ca2+ ion in the reaction system can be easily removed.Comparing to traditional technology of HNO3 oxidation,this process is more environmental-friendly and conserves more resources.
2012, 29(5): 537-544
doi: 10.3724/SP.J.1095.2012.00286
Abstract:
Ni/Al2O3 catalysts have been prepared through either impregnation or coprecipitation methods.The effects of Ni loading,preparation method and reaction temperature on the methane catalytic decomposition have been investigated.The results indicated that 20%(mass fraction) Ni/Al2O3 of which the average particle size of Ni was about 11.25 nm showed the best catalytic performance among the impregnated catalysts.The yields of carbon for per gram Ni and hydrogen for per mole Ni on such catalyst were 15.30 g and 164 mol,respectively.On the coprecipitated Ni/Al2O3,both the catalytic activity and lifespan of catalyst were improved.The deposited filamentous carbon over coprecipitated Ni/Al2O3 was much longer and more homogeneous than that generated over impregnated Ni/Al2O3.The methane catalytic conversion on coprecipitated Ni/Al2O3(41.2% mass fraction)remained higher than 30% after running the reaction at 550℃ up to 350 min.
Ni/Al2O3 catalysts have been prepared through either impregnation or coprecipitation methods.The effects of Ni loading,preparation method and reaction temperature on the methane catalytic decomposition have been investigated.The results indicated that 20%(mass fraction) Ni/Al2O3 of which the average particle size of Ni was about 11.25 nm showed the best catalytic performance among the impregnated catalysts.The yields of carbon for per gram Ni and hydrogen for per mole Ni on such catalyst were 15.30 g and 164 mol,respectively.On the coprecipitated Ni/Al2O3,both the catalytic activity and lifespan of catalyst were improved.The deposited filamentous carbon over coprecipitated Ni/Al2O3 was much longer and more homogeneous than that generated over impregnated Ni/Al2O3.The methane catalytic conversion on coprecipitated Ni/Al2O3(41.2% mass fraction)remained higher than 30% after running the reaction at 550℃ up to 350 min.
2012, 29(5): 545-550
doi: 10.3724/SP.J.1095.2012.00263
Abstract:
5-Nitrosalicylaldehyde was synthesized by the nitration of salicylaldehyde with nitric acid over H6PMo9V3O40 supported on silica gel.The effects of parameters were investigated,such as H6PMo9V3O40 loading,reaction time,temperature,solvent,and so on.Under the optimal conditions:m(salicylaldehyde):m(65%HNO3):m(20% H6PMo9V3O40/SiO2)=2.44:3.00:3.00,in petroleum ether at 45℃ for 2.5 h,the conversion of salicylaldehyde was 98%,the selectivity of 5-nitrosalicylaldehyde was up to 96.8%.The catalyst could be recovered easily and reused for five times without noticeable drop in activity.
5-Nitrosalicylaldehyde was synthesized by the nitration of salicylaldehyde with nitric acid over H6PMo9V3O40 supported on silica gel.The effects of parameters were investigated,such as H6PMo9V3O40 loading,reaction time,temperature,solvent,and so on.Under the optimal conditions:m(salicylaldehyde):m(65%HNO3):m(20% H6PMo9V3O40/SiO2)=2.44:3.00:3.00,in petroleum ether at 45℃ for 2.5 h,the conversion of salicylaldehyde was 98%,the selectivity of 5-nitrosalicylaldehyde was up to 96.8%.The catalyst could be recovered easily and reused for five times without noticeable drop in activity.
2012, 29(5): 551-556
doi: 10.3724/SP.J.1095.2012.00276
Abstract:
The adsorption behavior of nicotinamide adenine dinucleotide(NAD+) on α-Al2O3 nanoparticles was studied using ultraviolet-visible(UV-Vis) absorption spectroscopy,X-ray diffraction(XRD),fluorescence and attenuated total reflectance-Fourier transform infrared(ATR-FTIR) spectroscopy.It was found that the amount of adsorbed NAD+ exhibited a strong dependence on pH and ionic strength of the solution,which suggested that the adsorption of NAD+ at α-Al2O3 nanoparticles was caused predominantly by the electrostatic adsorption.ATR-FTIR spectra of adsorbed NAD+ were similar to those of NAD+ in solution.However,the position of peaks for phosphate moving to slightly higher wavenumbers suggested that phosphate participated into the electrostatic adsorption.The adsorption isotherm could be fitted with both Langmuir and Freundlich isotherms.The fluorescence spectral features showed that the conformation of NAD+ changed with the change of the amount of α-Al2O3 nanoparticles.
The adsorption behavior of nicotinamide adenine dinucleotide(NAD+) on α-Al2O3 nanoparticles was studied using ultraviolet-visible(UV-Vis) absorption spectroscopy,X-ray diffraction(XRD),fluorescence and attenuated total reflectance-Fourier transform infrared(ATR-FTIR) spectroscopy.It was found that the amount of adsorbed NAD+ exhibited a strong dependence on pH and ionic strength of the solution,which suggested that the adsorption of NAD+ at α-Al2O3 nanoparticles was caused predominantly by the electrostatic adsorption.ATR-FTIR spectra of adsorbed NAD+ were similar to those of NAD+ in solution.However,the position of peaks for phosphate moving to slightly higher wavenumbers suggested that phosphate participated into the electrostatic adsorption.The adsorption isotherm could be fitted with both Langmuir and Freundlich isotherms.The fluorescence spectral features showed that the conformation of NAD+ changed with the change of the amount of α-Al2O3 nanoparticles.
2012, 29(5): 557-564
doi: 10.3724/SP.J.1095.2012.00382
Abstract:
PbS nanobelts were synthesized by a facile hydrothermal method using lead nitrate,thioacetamide and dodecyl benzene sulfonate(SDBS) as raw materials.SDBS played a dual role as both the starting material and surfactant in the reaction.The as-prepared nanobelts were characterized by transmission electron microscopy and X-ray diffraction.The photoluminescence property of the nanobelts was also studied.It was concluded that the intermediate PbSO4 could act as a template for the growth of PbS nanobelts under hydrothermal conditions.The formation mechanism of nanobelts was further investigated.The results indicated that the intermediate PbSO4 could paly restriction effect on the surfactant(SDBS).When PbSO4 was replaced by other lead composite,the surfactant would lose its role and irregular micro-crystals were obtained consequently.The formation of nanobelts was readily controlled under a slow reaction speed.The result presented here may open an efficient way to synthesizing nanobelts with different morphologies.
PbS nanobelts were synthesized by a facile hydrothermal method using lead nitrate,thioacetamide and dodecyl benzene sulfonate(SDBS) as raw materials.SDBS played a dual role as both the starting material and surfactant in the reaction.The as-prepared nanobelts were characterized by transmission electron microscopy and X-ray diffraction.The photoluminescence property of the nanobelts was also studied.It was concluded that the intermediate PbSO4 could act as a template for the growth of PbS nanobelts under hydrothermal conditions.The formation mechanism of nanobelts was further investigated.The results indicated that the intermediate PbSO4 could paly restriction effect on the surfactant(SDBS).When PbSO4 was replaced by other lead composite,the surfactant would lose its role and irregular micro-crystals were obtained consequently.The formation of nanobelts was readily controlled under a slow reaction speed.The result presented here may open an efficient way to synthesizing nanobelts with different morphologies.
2012, 29(5): 565-570
doi: 10.3724/SP.J.1095.2012.00267
Abstract:
The rheological behavior of a lamellar lyotropic liquid crystal formed from nonyl phenol ethoxylate(10)(NP-10)/water was investigated using a rheometer.The influence of composition and temperature on the dynamic function was studied at varied surfactant concentration and temperature.The frequency-dependent storage and loss modulus were found not to be consistent with the Maxwell model in the linear viscoelastic region.The results were analyzed on the basis of slip-plane theory.The compliance was also measured,and the instantaneous elasticity measured in the creep tests was in according with the oscillatory tests.Burgers model was used to describe the time-dependent compliance.
The rheological behavior of a lamellar lyotropic liquid crystal formed from nonyl phenol ethoxylate(10)(NP-10)/water was investigated using a rheometer.The influence of composition and temperature on the dynamic function was studied at varied surfactant concentration and temperature.The frequency-dependent storage and loss modulus were found not to be consistent with the Maxwell model in the linear viscoelastic region.The results were analyzed on the basis of slip-plane theory.The compliance was also measured,and the instantaneous elasticity measured in the creep tests was in according with the oscillatory tests.Burgers model was used to describe the time-dependent compliance.
2012, 29(5): 571-575
doi: 10.3724/SP.J.1095.2012.00285
Abstract:
The micelle aggregation numbers of C12-3-C12·2Br and C12-3(OH)-C12·2Br were measured by the technique of fluorescence probe.It was found that the concentration of the Gemini surfactants had great influences on their micelle aggregation number,owing to the presence of hydroxyl group in spacer.When the concentrations were set as 5.5cmc,the aggregation number of C12-3(OH)-C12·2Br was 44.7 and was much greater than that of C12-3-C12·Br(33.2).The two surfactants followed the Newtonian flow with their shear rates γ in the range of 0~1 875 s-1 for the concentrations of C12-3-C12·2Br and C12-3(OH)-C12·2Br up to 64 mmol/L and 54 mmol/L,respectively.Beyond these,the shear rates are higher than their critical values(γ*) and then the flow transformed from Newtonian to non-Newtonian modes.In addition,the viscosity η increased with the increase of concentration accompanied with a sharp increase.It was found that the introduction of -OH into the spaces has barely effect on their flow behaviors but cause a slight increase of η.
The micelle aggregation numbers of C12-3-C12·2Br and C12-3(OH)-C12·2Br were measured by the technique of fluorescence probe.It was found that the concentration of the Gemini surfactants had great influences on their micelle aggregation number,owing to the presence of hydroxyl group in spacer.When the concentrations were set as 5.5cmc,the aggregation number of C12-3(OH)-C12·2Br was 44.7 and was much greater than that of C12-3-C12·Br(33.2).The two surfactants followed the Newtonian flow with their shear rates γ in the range of 0~1 875 s-1 for the concentrations of C12-3-C12·2Br and C12-3(OH)-C12·2Br up to 64 mmol/L and 54 mmol/L,respectively.Beyond these,the shear rates are higher than their critical values(γ*) and then the flow transformed from Newtonian to non-Newtonian modes.In addition,the viscosity η increased with the increase of concentration accompanied with a sharp increase.It was found that the introduction of -OH into the spaces has barely effect on their flow behaviors but cause a slight increase of η.
2012, 29(5): 576-584
doi: 10.3724/SP.J.1095.2012.00287
Abstract:
A silver doped poly(L-methionine) modified glassy carbon electrode was fabricated through cyclic voltammetric method.The electrochemical behaviors of hydroquinone and catechol on the silver doped poly(L-methionine) modified electrode were investigated.In a phosphate buffer solution with pH=5.0,the modified electrode gave a pair of redox peaks at Epa=0.228 V,Epc=0.162 V for hydroquinone and Epa=0.347 V,Epc=0.287 V for catechol at the scan rates of 100 mV/s.Two peak differences for oxidation or reduction were 119 mV or 125 mV,respectively.Under optimized conditions,the oxidation peak currents were proportional to the concentrations of hydroquinone and catechol,respectively.The linear ranges for the simultaneous determination of hydroquinone and catechol using differential pulse voltammetry were 3.00×10-6~1.00×10-4 mol/L.The detection limits were 8.0×10-7 mol/L for hydroquinone and 5.0×10-7 mol/L for catechol,respectively.The as-established protocol was successfully applied for the simultaneous determination of hydroquinone and catechol in waste water samples with satisfactory results.
A silver doped poly(L-methionine) modified glassy carbon electrode was fabricated through cyclic voltammetric method.The electrochemical behaviors of hydroquinone and catechol on the silver doped poly(L-methionine) modified electrode were investigated.In a phosphate buffer solution with pH=5.0,the modified electrode gave a pair of redox peaks at Epa=0.228 V,Epc=0.162 V for hydroquinone and Epa=0.347 V,Epc=0.287 V for catechol at the scan rates of 100 mV/s.Two peak differences for oxidation or reduction were 119 mV or 125 mV,respectively.Under optimized conditions,the oxidation peak currents were proportional to the concentrations of hydroquinone and catechol,respectively.The linear ranges for the simultaneous determination of hydroquinone and catechol using differential pulse voltammetry were 3.00×10-6~1.00×10-4 mol/L.The detection limits were 8.0×10-7 mol/L for hydroquinone and 5.0×10-7 mol/L for catechol,respectively.The as-established protocol was successfully applied for the simultaneous determination of hydroquinone and catechol in waste water samples with satisfactory results.
2012, 29(5): 585-590
doi: 10.3724/SP.J.1095.2012.00268
Abstract:
Para aminobenzene sulfonic acid(p-ABSA) was deposited onto the surface of a glass carbon electrode(GCE) through the electrochemical deposition.Cation-exchange properties of the deposited p-ABSA were then employed to confine ferric ion(Fe3+) within the polymeric layer.Ferrocyanide ions([Fe(CN)6]4-) can react with the adsorbed Fe3+ forming Prussian blue(PB).PB crystals were formed by alternative adsorption of Fe3+ and reaction with[Fe(CN)6]4-.The crystal shows high catalytic activity toward the electrochemical reduction of hydrogen peroxide.Cyclic voltammetry,electrochemical impedance spectroscopy and typical amperometric response method were employed to characterize the electrochemical properties of the PB modified electrode.The experimental parameters(applied potential,pH,and interfering substances) influencing the performance of the PB modified electrode were investigated in details.Under optimal conditions,the PB modified electrode exhibits a wider linear range of 0.97~32.33 mmol/L with the fast response less than 5 s and a low detection limit of 0.48 mmol/L(S/N=3).
Para aminobenzene sulfonic acid(p-ABSA) was deposited onto the surface of a glass carbon electrode(GCE) through the electrochemical deposition.Cation-exchange properties of the deposited p-ABSA were then employed to confine ferric ion(Fe3+) within the polymeric layer.Ferrocyanide ions([Fe(CN)6]4-) can react with the adsorbed Fe3+ forming Prussian blue(PB).PB crystals were formed by alternative adsorption of Fe3+ and reaction with[Fe(CN)6]4-.The crystal shows high catalytic activity toward the electrochemical reduction of hydrogen peroxide.Cyclic voltammetry,electrochemical impedance spectroscopy and typical amperometric response method were employed to characterize the electrochemical properties of the PB modified electrode.The experimental parameters(applied potential,pH,and interfering substances) influencing the performance of the PB modified electrode were investigated in details.Under optimal conditions,the PB modified electrode exhibits a wider linear range of 0.97~32.33 mmol/L with the fast response less than 5 s and a low detection limit of 0.48 mmol/L(S/N=3).
2012, 29(5): 591-596
doi: 10.3724/SP.J.1095.2012.00269
Abstract:
A simple,rapid and sensitive HPLC-MS method was developed and validated for determining bezafibrate in rat plasma.Chromatographic separation was achieved on a reversed-phase Gemini C18 at 35℃ using acetonitrile,methanol and 0.03% aqueous solution of formic acid(volume ratio 60:15:25) as mobile phase at flow rate of 0.3 mL/min.The UV absorption wavelength was set at 235 nm and the injection volume was 5 μL.Under these conditions,the detection was performed with negative electrospray ionization,monitoring the transitions m/z 359.65→273.70 for bezafibrate and m/z 212.95→127.08 for the clofibric acid(internal standard).A good linearity was achieved within the concentration range of 0.073~7.884 mg/L(r=0.9995) for bezafibrate and the mean recovery of samples ranged from 94.3% to 103.1% at three tested concentrations.The intra-day and inter-day precisions(as relative standard deviation) were below 6%.The limit of quantification(LOQ) was 30 μg/L and the limit of detection(LOD) was 9 μg/L.This HPLC-MS method was reproducible and sensitive enough for routine analysis of bezafibrate in human plasma.
A simple,rapid and sensitive HPLC-MS method was developed and validated for determining bezafibrate in rat plasma.Chromatographic separation was achieved on a reversed-phase Gemini C18 at 35℃ using acetonitrile,methanol and 0.03% aqueous solution of formic acid(volume ratio 60:15:25) as mobile phase at flow rate of 0.3 mL/min.The UV absorption wavelength was set at 235 nm and the injection volume was 5 μL.Under these conditions,the detection was performed with negative electrospray ionization,monitoring the transitions m/z 359.65→273.70 for bezafibrate and m/z 212.95→127.08 for the clofibric acid(internal standard).A good linearity was achieved within the concentration range of 0.073~7.884 mg/L(r=0.9995) for bezafibrate and the mean recovery of samples ranged from 94.3% to 103.1% at three tested concentrations.The intra-day and inter-day precisions(as relative standard deviation) were below 6%.The limit of quantification(LOQ) was 30 μg/L and the limit of detection(LOD) was 9 μg/L.This HPLC-MS method was reproducible and sensitive enough for routine analysis of bezafibrate in human plasma.
2012, 29(5): 597-603
doi: 10.3724/SP.J.1095.2012.00280
Abstract:
In hydrochloric acid solution of pH=3.2,ferrum(Ⅲ) can oxidize I-into the form of I3- and acridine red(AR) can react with I3- to form of AR-I3 ion association complexes(the composition stoichiometry was defined as n(I3-):n(AR)=1:1).The association complexes automatically aggregate to(AR-I3)n association particles.In this case,the resonance light scattering(RLS) intensities are enhanced greatly.The maximum RLS wavelength locates at 468 nm.The optimum conditions of the reaction,influence factors and the effect of coexisting substances were investigated.In addition,the reaction mechanism of the ion-association complex was discussed.The resonance scattering intensity(ΔI468 nm) was linearly related to the concentration of ferrum(Ⅲ) in the range of 0.08~0.56 mg/L with a detection limit of 5.76×10-7 g/L.The assay was applied to the detection of trace ferrum(Ⅲ) in realistic samples,with a RSD of 3.3% and the recovery range of 96.0%~102.4%,and the results were in a good agreement with that of atomic absorption spectrometry assay.
In hydrochloric acid solution of pH=3.2,ferrum(Ⅲ) can oxidize I-into the form of I3- and acridine red(AR) can react with I3- to form of AR-I3 ion association complexes(the composition stoichiometry was defined as n(I3-):n(AR)=1:1).The association complexes automatically aggregate to(AR-I3)n association particles.In this case,the resonance light scattering(RLS) intensities are enhanced greatly.The maximum RLS wavelength locates at 468 nm.The optimum conditions of the reaction,influence factors and the effect of coexisting substances were investigated.In addition,the reaction mechanism of the ion-association complex was discussed.The resonance scattering intensity(ΔI468 nm) was linearly related to the concentration of ferrum(Ⅲ) in the range of 0.08~0.56 mg/L with a detection limit of 5.76×10-7 g/L.The assay was applied to the detection of trace ferrum(Ⅲ) in realistic samples,with a RSD of 3.3% and the recovery range of 96.0%~102.4%,and the results were in a good agreement with that of atomic absorption spectrometry assay.
2012, 29(5): 604-607
doi: 10.3724/SP.J.1095.2012.00289
Abstract:
With acrylamide-β-cyclodextrin(AM-β-CD) and glycidyl methacrylate acting as functional monomers,and ethylene glycol dimethacrylate acting as cross-linking agent,the chiral capillary monolithic column of acrylamide-β-cyclodextrin was prepared by in situ polymerization method.The structure and morphology of the monolithic column were characterized by IR and scanning electron microscopy(SEM).Meanwhile,the stability and reproducibility were also studied.The results showed that the capillary monolithic column of acrylamide-β-cyclodextrin had a good separation ability,and the column efficiency of 47701 plates/m was obtained.In capillary electrochromatography(CEC) mode,the etilefrine hydrochloride enantiomers were firstly separated by the chiral capillary monolithic column of acrylamide-β-cyclodextrin.Herein,the baseline resolutions of the enantiomers were completely reached.
With acrylamide-β-cyclodextrin(AM-β-CD) and glycidyl methacrylate acting as functional monomers,and ethylene glycol dimethacrylate acting as cross-linking agent,the chiral capillary monolithic column of acrylamide-β-cyclodextrin was prepared by in situ polymerization method.The structure and morphology of the monolithic column were characterized by IR and scanning electron microscopy(SEM).Meanwhile,the stability and reproducibility were also studied.The results showed that the capillary monolithic column of acrylamide-β-cyclodextrin had a good separation ability,and the column efficiency of 47701 plates/m was obtained.In capillary electrochromatography(CEC) mode,the etilefrine hydrochloride enantiomers were firstly separated by the chiral capillary monolithic column of acrylamide-β-cyclodextrin.Herein,the baseline resolutions of the enantiomers were completely reached.
2012, 29(5): 608-610
doi: 10.3724/SP.J.1095.2012.00298
Abstract:
A new meso-tetra[4-(5-fluorouracil-1-yl acetoxyl)phenyl]porphyrin compound(A) was synthesized from meso-tetra(4-hydroxyphenyl) porphyrin with 5-fluorouracil-1-yl acetic acid by using N,N'-dicyclohexylcarbdiimide as dehydration agent with a yield of 12.7%.The zinc complex(B) of the compound was prepared by the reaction of porphyrin(A) with Zn(OAc)2 with a yield of 30.8%.The structures of the products were characterized by UV-Vis,IR,1H NMR,MS and elemental analysis.
A new meso-tetra[4-(5-fluorouracil-1-yl acetoxyl)phenyl]porphyrin compound(A) was synthesized from meso-tetra(4-hydroxyphenyl) porphyrin with 5-fluorouracil-1-yl acetic acid by using N,N'-dicyclohexylcarbdiimide as dehydration agent with a yield of 12.7%.The zinc complex(B) of the compound was prepared by the reaction of porphyrin(A) with Zn(OAc)2 with a yield of 30.8%.The structures of the products were characterized by UV-Vis,IR,1H NMR,MS and elemental analysis.
