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2011 Volume 28 Issue 6
2011, 28(6): 611-623
doi: 10.3724/SP.J.1095.2011.00455
Abstract:
Biosensors have received vigorous development and serious concern in recent years owing to the combinations with nanotechniques,flow-injection and micro-fluidics devices.Affinitive biosensor is a kind of high-tech sensing device based on the specific affinity between biological molecules,and the affinity of bioactive substance and substrate.With the advantages of high specificity,good sensitivity,high speed,low cost,on-line measuring and monitoring in complicated system,affinitive biosensors are widely used in biomedical fields,such as the detection of biomedical markers,nucleic acids,proteins,viruses,bacteria and toxins,the research of medicine actions mechanism,clinical drug screening,and etc.In this paper,the recent advance of affinitive biosensors in biomedical applications are reviewed.We also focus on a growing number of applications and progress in immunosensors and aptamer-based biosensors for tumor biomarker,nucleic acids and proteins.It covers the basic principles and biomedical and clinical applications of immunosensors and aptamer-based biosensors,and indicates the future prospects in this field.
Biosensors have received vigorous development and serious concern in recent years owing to the combinations with nanotechniques,flow-injection and micro-fluidics devices.Affinitive biosensor is a kind of high-tech sensing device based on the specific affinity between biological molecules,and the affinity of bioactive substance and substrate.With the advantages of high specificity,good sensitivity,high speed,low cost,on-line measuring and monitoring in complicated system,affinitive biosensors are widely used in biomedical fields,such as the detection of biomedical markers,nucleic acids,proteins,viruses,bacteria and toxins,the research of medicine actions mechanism,clinical drug screening,and etc.In this paper,the recent advance of affinitive biosensors in biomedical applications are reviewed.We also focus on a growing number of applications and progress in immunosensors and aptamer-based biosensors for tumor biomarker,nucleic acids and proteins.It covers the basic principles and biomedical and clinical applications of immunosensors and aptamer-based biosensors,and indicates the future prospects in this field.
2011, 28(6): 624-628
doi: 10.3724/SP.J.1095.2011.00512
Abstract:
Polyampholyte microspheres with pH and salt concentration sensitive behaviors were prepared by acrylamide(AM),acryloylxyethyl trimethyl ammonium chloride(DAC) and methacrylic acid(MAA) in ethanol.The shape and conformation of microspheres were determined by transmission electron microscope and infrared spectroscopy,respectively.Meanwhile,the change behavior of the microsphere diameter in various pH solutions and in NaCl and CaCl2 salt solutions was investigated.The results indicated that the diameter of microspheres was 1 177 nm,and polydispersity index(PDI) value was 0.181 at the second step,which were greater than those(d=764 nm;PDI=0.069) at the first step.The diameter of microspheres increased with decreasing pH when the pH was lower than pH=4.3.Whereas when the pH was higher than 4.3,the diameter increased with increasing pH,and a minimum diameter was obtained when the pH was 4.3.At the isoelectric point,the dispersion exhibited a typical antipolyelectrolyte effect in univalent NaCl salt solution.However,in multivalent CaCl2 salt solution,the diameter of microspheres first increased and then decreased.
Polyampholyte microspheres with pH and salt concentration sensitive behaviors were prepared by acrylamide(AM),acryloylxyethyl trimethyl ammonium chloride(DAC) and methacrylic acid(MAA) in ethanol.The shape and conformation of microspheres were determined by transmission electron microscope and infrared spectroscopy,respectively.Meanwhile,the change behavior of the microsphere diameter in various pH solutions and in NaCl and CaCl2 salt solutions was investigated.The results indicated that the diameter of microspheres was 1 177 nm,and polydispersity index(PDI) value was 0.181 at the second step,which were greater than those(d=764 nm;PDI=0.069) at the first step.The diameter of microspheres increased with decreasing pH when the pH was lower than pH=4.3.Whereas when the pH was higher than 4.3,the diameter increased with increasing pH,and a minimum diameter was obtained when the pH was 4.3.At the isoelectric point,the dispersion exhibited a typical antipolyelectrolyte effect in univalent NaCl salt solution.However,in multivalent CaCl2 salt solution,the diameter of microspheres first increased and then decreased.
2011, 28(6): 629-633
doi: 10.3724/SP.J.1095.2011.00469
Abstract:
Dicyclopentadiene phenol resin(DPR) was prepared from dicyclopentadiene and phenol with methane sulfonic acid as the catalyst.The optimum conditions for the synthesis were as follows:n(phenol)/n(DCPD)=5;w(catalyst)=1.5%;temperature=120℃;time=5 h;yield=89%.The light yellow dicyclopentadiene phenol resin was obtained by the decolouring of catalytic-hydrogenation.The optimal conditions for the decolorization were as follows:hydrogen pressure=1.5 MPa,w(Pd/Al2O3)=0.5%,temperature=80℃,yield=89%.FT-IR and 1H NMR analysis identified the desired product.The product properties reached the international quality standards.
Dicyclopentadiene phenol resin(DPR) was prepared from dicyclopentadiene and phenol with methane sulfonic acid as the catalyst.The optimum conditions for the synthesis were as follows:n(phenol)/n(DCPD)=5;w(catalyst)=1.5%;temperature=120℃;time=5 h;yield=89%.The light yellow dicyclopentadiene phenol resin was obtained by the decolouring of catalytic-hydrogenation.The optimal conditions for the decolorization were as follows:hydrogen pressure=1.5 MPa,w(Pd/Al2O3)=0.5%,temperature=80℃,yield=89%.FT-IR and 1H NMR analysis identified the desired product.The product properties reached the international quality standards.
2011, 28(6): 634-639
doi: 10.3724/SP.J.1095.2011.00397
Abstract:
A new hydrophilic functional chelating resin(CTS-AMT) with heterocyclic group were synthesized by the graft reaction between 2-amino-5-mercapto-1,3,4-thiadizole(AMT) and macroporous Schiff base chitosan(CTS)-chelated bead.The structure of the resin was confirmed by FTIR spectra and elemental analysis.The adsorption property and the selectivity of CTS-AMT and the parent chitosan for Cd2+,Zn2+,Cu2+,Pb2+,Ag+ and Hg2+ were compared.The experimental results show that CTS-AMT has a higher adsorption capacity and a better selectivity than CTS as expected.In the solution of pH=5.0,T=298.15 K,the adsorption of resin on metal ions can be accomplished in about 1.5 h.The static adsorption capacities for Hg2+,Ag+ and Pb2+ are 2.54,2.31,and 1.71 mmol/g,respectively.It shows that the adsorption isotherms approximately follows Langmuir isotherm equation under the experimental concentrations.
A new hydrophilic functional chelating resin(CTS-AMT) with heterocyclic group were synthesized by the graft reaction between 2-amino-5-mercapto-1,3,4-thiadizole(AMT) and macroporous Schiff base chitosan(CTS)-chelated bead.The structure of the resin was confirmed by FTIR spectra and elemental analysis.The adsorption property and the selectivity of CTS-AMT and the parent chitosan for Cd2+,Zn2+,Cu2+,Pb2+,Ag+ and Hg2+ were compared.The experimental results show that CTS-AMT has a higher adsorption capacity and a better selectivity than CTS as expected.In the solution of pH=5.0,T=298.15 K,the adsorption of resin on metal ions can be accomplished in about 1.5 h.The static adsorption capacities for Hg2+,Ag+ and Pb2+ are 2.54,2.31,and 1.71 mmol/g,respectively.It shows that the adsorption isotherms approximately follows Langmuir isotherm equation under the experimental concentrations.
2011, 28(6): 640-644
doi: 10.3724/SP.J.1095.2011.00425
Abstract:
Hydrosilylation reaction of 4-vinylbenzocyclobutene(4-VBCB) with 1,1,3,3-tetramethyl-1,3-dihydro disiloxane(TMHS) was employed to afford the monomer of diethyl tetramethyl disiloxanebisbenzocyclobutene(DES-bis-BCB).The structures of DES-bis-BCB and the prepolymer prepared from DESbis-BCB by thermal isomerization ring opening polymerization reaction were characterized and analyzed.The surface morphology and thermal stability of the films were investigated by atomic force microscopy(AFM) and thermogravimetric analysis(TGA),respectively.The results showed that the root-mean square(RMS) roughness was 0.53 nm,and the starting mass loss temperature was about 390℃.It indicated that DES-bisBCB exhibited good film-forming property and excellent thermal stability.
Hydrosilylation reaction of 4-vinylbenzocyclobutene(4-VBCB) with 1,1,3,3-tetramethyl-1,3-dihydro disiloxane(TMHS) was employed to afford the monomer of diethyl tetramethyl disiloxanebisbenzocyclobutene(DES-bis-BCB).The structures of DES-bis-BCB and the prepolymer prepared from DESbis-BCB by thermal isomerization ring opening polymerization reaction were characterized and analyzed.The surface morphology and thermal stability of the films were investigated by atomic force microscopy(AFM) and thermogravimetric analysis(TGA),respectively.The results showed that the root-mean square(RMS) roughness was 0.53 nm,and the starting mass loss temperature was about 390℃.It indicated that DES-bisBCB exhibited good film-forming property and excellent thermal stability.
2011, 28(6): 645-651
doi: 10.3724/SP.J.1095.2011.00502
Abstract:
In order to find more stable and effective antibacterial compounds,we screened some N-(5-chloro-2-hydroxybenzyl) amino acid ester with good antibacterial activities.Twenty metal-amino complexes with 1:1 molar ratio of ligand to metal cation were synthesized via a step-by-step method in alkaline aqueous solutions or water-methanol mixed solvents at room temperature.These complexes and the structures of the compounds were confirmed by 1H NMR,IR and UV.It was found that the hydroxyl group,amine group and carboxyl group of ligands could coordinate with metal cations.Preliminary bioassay results showed that nearly all the metal complexes have better anti-bacteria activities than their counterpart ligands,especially for the Monilia albicans which has a 100% inhibitory ratio.The conditions of the preparation of N-(5-chloro-2-hydroxyphenyl) amino acid ester schiff-base were optimized.
In order to find more stable and effective antibacterial compounds,we screened some N-(5-chloro-2-hydroxybenzyl) amino acid ester with good antibacterial activities.Twenty metal-amino complexes with 1:1 molar ratio of ligand to metal cation were synthesized via a step-by-step method in alkaline aqueous solutions or water-methanol mixed solvents at room temperature.These complexes and the structures of the compounds were confirmed by 1H NMR,IR and UV.It was found that the hydroxyl group,amine group and carboxyl group of ligands could coordinate with metal cations.Preliminary bioassay results showed that nearly all the metal complexes have better anti-bacteria activities than their counterpart ligands,especially for the Monilia albicans which has a 100% inhibitory ratio.The conditions of the preparation of N-(5-chloro-2-hydroxyphenyl) amino acid ester schiff-base were optimized.
2011, 28(6): 652-656
doi: 10.3724/SP.J.1095.2011.00427
Abstract:
Rhuschalcone Ⅰ was adopted to two synthetic fragments,compound 8 and compound 10,then the two fragments were combined together.Rhuschalcone Ⅰ were first synthesized by selective methylation,iodination,methoxymethylation,aldol condensation,Ullmann reaction,deprotection from m-dihydroxybenzene and p-hydroxybenzaldehyde.The chemical structures of the key intermediate and the final target product were verified by 1H NMR,13C NMR and ESI-MS.
Rhuschalcone Ⅰ was adopted to two synthetic fragments,compound 8 and compound 10,then the two fragments were combined together.Rhuschalcone Ⅰ were first synthesized by selective methylation,iodination,methoxymethylation,aldol condensation,Ullmann reaction,deprotection from m-dihydroxybenzene and p-hydroxybenzaldehyde.The chemical structures of the key intermediate and the final target product were verified by 1H NMR,13C NMR and ESI-MS.
2011, 28(6): 657-661
doi: 10.3724/SP.J.1095.2011.00459
Abstract:
3,8-Bis-(1-hydroxyethyl) deuteroporphyrin dimethyl ester(Ⅲ) was prepared from hemin(I) by the ways of HBr-H3CCOOH addition reaction,OH- nucleophilic substitution reaction and anhydrous hydrogen chloride catalyzed esterification.It was then oxidized by Jones reagent to form 3,8-bisacetyl deuteroporphyrin dimethyl ester(Ⅳ).The effects of reaction temperature and reaction time on the yield of 3,8-bis-(1-hydroxyethyl) deuteroporphyrin dimethyl ester(Ⅱ) were studied.The conditions of esterification reaction were modified.A cheaper and selective oxidant was used in the synthesization of 3,8-bisacetyl deuteroporphyrin dimethyl ester(Ⅳ).The results showed that the yield of hematoporphyrin(Ⅱ) reaches to the highest of 98.5% when the temperature is 35℃ and the reaction time is 25 h.The yield of hematoporphyrin dimethyl ester is 72.1% when the catalyst is anhydrous hydrogen chloride.The cost of 3,8-bisacetyl deuteroporphyrin dimethyl ester(Ⅳ) was decreased greatly when the oxidant is Jones reagent.The target products were characterized with 1H NMR,IR and MS.
3,8-Bis-(1-hydroxyethyl) deuteroporphyrin dimethyl ester(Ⅲ) was prepared from hemin(I) by the ways of HBr-H3CCOOH addition reaction,OH- nucleophilic substitution reaction and anhydrous hydrogen chloride catalyzed esterification.It was then oxidized by Jones reagent to form 3,8-bisacetyl deuteroporphyrin dimethyl ester(Ⅳ).The effects of reaction temperature and reaction time on the yield of 3,8-bis-(1-hydroxyethyl) deuteroporphyrin dimethyl ester(Ⅱ) were studied.The conditions of esterification reaction were modified.A cheaper and selective oxidant was used in the synthesization of 3,8-bisacetyl deuteroporphyrin dimethyl ester(Ⅳ).The results showed that the yield of hematoporphyrin(Ⅱ) reaches to the highest of 98.5% when the temperature is 35℃ and the reaction time is 25 h.The yield of hematoporphyrin dimethyl ester is 72.1% when the catalyst is anhydrous hydrogen chloride.The cost of 3,8-bisacetyl deuteroporphyrin dimethyl ester(Ⅳ) was decreased greatly when the oxidant is Jones reagent.The target products were characterized with 1H NMR,IR and MS.
2011, 28(6): 662-667
doi: 10.3724/SP.J.1095.2011.00435
Abstract:
Trans-1,2-cyclohexanediol was synthesized by the oxidation of cyclohexene using H2O2 as the oxidant and ionic liquids(ILs) as the catalyst and solvent.The effects of different imidazolium ionic liquids,reaction time,reaction temperature and the amount of H2O2 on the yield and selectivity of trans-1,2-cyclohexanediol were investigated.The experimental results showed that ionic liquids based on imidazolium cations containing 1~2 carboxyl groups and [PF6] anion exhibited the highest catalytic activities among the seven imidazolium ionic liquids.Under optimized conditions:reaction temperature 100℃,n(H2O2):n(cyclohexene)=1.1:1,and reaction time 5 h,the yield and selectivity of trans-1,2-cyclohexanediol were 95% and 97% with IL c(0.60 g,2.1 mmol) as the catalyst,and 84% and 90% with IL f(0.20 g,0.6 mmol) as the catalyst,respectively.From the dosage of ionic liquid,it can be seen the catalytic efficiency of IL f containing two carboxyl groups was higher.
Trans-1,2-cyclohexanediol was synthesized by the oxidation of cyclohexene using H2O2 as the oxidant and ionic liquids(ILs) as the catalyst and solvent.The effects of different imidazolium ionic liquids,reaction time,reaction temperature and the amount of H2O2 on the yield and selectivity of trans-1,2-cyclohexanediol were investigated.The experimental results showed that ionic liquids based on imidazolium cations containing 1~2 carboxyl groups and [PF6] anion exhibited the highest catalytic activities among the seven imidazolium ionic liquids.Under optimized conditions:reaction temperature 100℃,n(H2O2):n(cyclohexene)=1.1:1,and reaction time 5 h,the yield and selectivity of trans-1,2-cyclohexanediol were 95% and 97% with IL c(0.60 g,2.1 mmol) as the catalyst,and 84% and 90% with IL f(0.20 g,0.6 mmol) as the catalyst,respectively.From the dosage of ionic liquid,it can be seen the catalytic efficiency of IL f containing two carboxyl groups was higher.
2011, 28(6): 668-672
doi: 10.3724/SP.J.1095.2011.00454
Abstract:
Catalysts of titanosilicate zeolite(TS-1) supported on silica gel microsphere were prepared after direct crystallization and calcination of the microspheric silica gel soaked in the TS-1 synthetic solution,in order to produce catalysts with good catalytic and recycling properties.The catalysts were characterized by XRD,IR and SEM,and were used in the synthesis of phenol by a direct oxidation of benzene with the hydrogen peroxide as the oxidant.The result showed that TS-1 molecular sieve was loaded on the surface of silica gel very well.On the conditions with the crystallization temperature at 160℃,crystallization time of 72 h,calcination temperature of 550℃,and calcination time of 6 h,the catalysts prepared showed good catalytic properties.On the conditions of the initial material content of benzene 0.5 mol and hydrogen peroxide 0.1 mol,catalyst 8 g,the reaction temperature at 60℃,and the reaction time 3 h,the convertion of benzene was 10.32%,and the selectivity to phenol was 97.12%.After recycling for nine times,the convertion of benzene was 9.42%,and the selectivity to phenol was 93.14%.
Catalysts of titanosilicate zeolite(TS-1) supported on silica gel microsphere were prepared after direct crystallization and calcination of the microspheric silica gel soaked in the TS-1 synthetic solution,in order to produce catalysts with good catalytic and recycling properties.The catalysts were characterized by XRD,IR and SEM,and were used in the synthesis of phenol by a direct oxidation of benzene with the hydrogen peroxide as the oxidant.The result showed that TS-1 molecular sieve was loaded on the surface of silica gel very well.On the conditions with the crystallization temperature at 160℃,crystallization time of 72 h,calcination temperature of 550℃,and calcination time of 6 h,the catalysts prepared showed good catalytic properties.On the conditions of the initial material content of benzene 0.5 mol and hydrogen peroxide 0.1 mol,catalyst 8 g,the reaction temperature at 60℃,and the reaction time 3 h,the convertion of benzene was 10.32%,and the selectivity to phenol was 97.12%.After recycling for nine times,the convertion of benzene was 9.42%,and the selectivity to phenol was 93.14%.
2011, 28(6): 673-677
doi: 10.3724/SP.J.1095.2011.00467
Abstract:
Trimethyltin chloride and mesoporous molecular sieve Al-MCM-41 were heated at 135℃ for 4.5 h under stirring conditions and nitrogen atmosphere,to obtain(CH3)3 Sn-O-MCM-41[(CH3)3 SnM].The composition,structure,and physical and chemical surface properties of the resulted solid were characterized by inductively coupled plasma mass spectrometry(ICP-MS),Fourier transform infrared spectroscopy(FTIR),N2 adsorption-desorption,NH3 chemisorption(NH3-TPD),X-ray diffraction(XRD),and transmission electron microscopy(TEM).The results showed that the grafting yield was 14.44% for Sn in mass fraction.TPD acid(NH3) of Al-MCM-41 before and after reaction with trimethyltin chloride increased from 0.652 6 mmol/g to 1.294 4 mmol/g.(CH3)3SnM resulted in a decrease of the surface areas and the pore size and an increase of the mesopous volume and surface acidity compared to Al-MCM-41.The thermal stability for the sample grafted with organotin was improved.The sample that was grafted with organotin on the Al-MCM-41 had the ordered hexagonal mesopore structure.The conversion rate is 96% when n(isoamyl alcohol):n(acetic acid)=1.0:1.0,w((CH3)3SnM)=5%,138℃ for 5 h,and the catalyst can be reused.A conversion rate of 86% can be attained when catalyst was reused five times under the same catalytic conditions.
Trimethyltin chloride and mesoporous molecular sieve Al-MCM-41 were heated at 135℃ for 4.5 h under stirring conditions and nitrogen atmosphere,to obtain(CH3)3 Sn-O-MCM-41[(CH3)3 SnM].The composition,structure,and physical and chemical surface properties of the resulted solid were characterized by inductively coupled plasma mass spectrometry(ICP-MS),Fourier transform infrared spectroscopy(FTIR),N2 adsorption-desorption,NH3 chemisorption(NH3-TPD),X-ray diffraction(XRD),and transmission electron microscopy(TEM).The results showed that the grafting yield was 14.44% for Sn in mass fraction.TPD acid(NH3) of Al-MCM-41 before and after reaction with trimethyltin chloride increased from 0.652 6 mmol/g to 1.294 4 mmol/g.(CH3)3SnM resulted in a decrease of the surface areas and the pore size and an increase of the mesopous volume and surface acidity compared to Al-MCM-41.The thermal stability for the sample grafted with organotin was improved.The sample that was grafted with organotin on the Al-MCM-41 had the ordered hexagonal mesopore structure.The conversion rate is 96% when n(isoamyl alcohol):n(acetic acid)=1.0:1.0,w((CH3)3SnM)=5%,138℃ for 5 h,and the catalyst can be reused.A conversion rate of 86% can be attained when catalyst was reused five times under the same catalytic conditions.
2011, 28(6): 678-682
doi: 10.3724/SP.J.1095.2011.00458
Abstract:
Hollow inorganic particles have attracted great interest because of their unique physicochemical properties.In this study,a simple and effective method for synthesizing silica hollow spheres is presented.The synthesis utilizes CaCO3 as spherical templates for the silica growth;tetraethyl orthosilicate(TEOS) is added to the template as a precursor for the silica formation.After CaCO3 spherical cores were removed by adding diluted hydrochloric acid,hollow silica spheres with smooth surface and uniform shell thickness around 60~70 nm were obtained.The core shell structure of CaCO3 sphere-silica composites and the hollow structure of silica spheres were characterized by FESEM,TEM,TGA,XRD and FTIR.The results indicated that the silica was coated on the surface of CaCO 3 spheres.The inner diameter of the hollow silica spheres with amorphous shell was about 1~2 μm.Amine functional silica hollow spheres were prepared via the hydrolysis of APTMs,then alginate was firstly grafted onto the surface of amine silica then the alginate coating was immobilized by gelling Ca2+ ions and alginate,which allows the formation of alginate-modified hollow SiO2.The size of microsphere is about 1~2 μm.Daunorubicin as a probing drug was loaded into the carrier,the maximum percent of envelop and load were 55.6% and 27.8% respectively.
Hollow inorganic particles have attracted great interest because of their unique physicochemical properties.In this study,a simple and effective method for synthesizing silica hollow spheres is presented.The synthesis utilizes CaCO3 as spherical templates for the silica growth;tetraethyl orthosilicate(TEOS) is added to the template as a precursor for the silica formation.After CaCO3 spherical cores were removed by adding diluted hydrochloric acid,hollow silica spheres with smooth surface and uniform shell thickness around 60~70 nm were obtained.The core shell structure of CaCO3 sphere-silica composites and the hollow structure of silica spheres were characterized by FESEM,TEM,TGA,XRD and FTIR.The results indicated that the silica was coated on the surface of CaCO 3 spheres.The inner diameter of the hollow silica spheres with amorphous shell was about 1~2 μm.Amine functional silica hollow spheres were prepared via the hydrolysis of APTMs,then alginate was firstly grafted onto the surface of amine silica then the alginate coating was immobilized by gelling Ca2+ ions and alginate,which allows the formation of alginate-modified hollow SiO2.The size of microsphere is about 1~2 μm.Daunorubicin as a probing drug was loaded into the carrier,the maximum percent of envelop and load were 55.6% and 27.8% respectively.
2011, 28(6): 683-688
doi: 10.3724/SP.J.1095.2011.00476
Abstract:
Monoclinic Ag2S nanoparticles and hexagonal CuS microstructures have been successfully prepared from solvent-extraction systems by a two-phase thermal method.In these systems,the extractant Cyanex 301(di-(2,4,4-trimethylpentyl) dithiophosphinic acid) acts as not only the surfactant but also the sulfur source.The products were characterized by powder X-ray diffraction(XRD),UV-Visible spectroscopy(UV-Vis),FTinfrared spectroscopy(FTIR) and transmission/scanning electron microscopy(TEM/SEM).It is found that the size of Ag2S nanoparticles becomes bigger with the increasing temperature and the morphology and size of CuS microstructures can be controlled by the feed concentration or temperature.
Monoclinic Ag2S nanoparticles and hexagonal CuS microstructures have been successfully prepared from solvent-extraction systems by a two-phase thermal method.In these systems,the extractant Cyanex 301(di-(2,4,4-trimethylpentyl) dithiophosphinic acid) acts as not only the surfactant but also the sulfur source.The products were characterized by powder X-ray diffraction(XRD),UV-Visible spectroscopy(UV-Vis),FTinfrared spectroscopy(FTIR) and transmission/scanning electron microscopy(TEM/SEM).It is found that the size of Ag2S nanoparticles becomes bigger with the increasing temperature and the morphology and size of CuS microstructures can be controlled by the feed concentration or temperature.
2011, 28(6): 689-694
doi: 10.3724/SP.J.1095.2011.00428
Abstract:
Water-soluble fluorescent CdSe quantum dots(QDs) were synthesized using thiolglycolic acid(TGA) as the stabilizer and characterized by fluorescence spectroscopy.The material exhibited strong visible fluorescence under excitation at 365 nm.QDs were applied to label blood fingerprints deposited on non-porous surfaces.Then fluorescent images of fingerprints were obtained by the charge-coupled device(CCD) camera.The effects of labeling time,blood concentration and stored time of blood fingerprints on imaging were investigated.The results showed that the fluorescent images could be obtained within labeling time of 30 min.CdSe QDs can detect blood fingerprints on different surfaces especially on black surface;1% diluted blood fingerprints also could be labeled.The labeled blood fingerprints have higher and stable fluorescence intensity,weaker background interference and better contrast between fingerprints and substrate.CdSe QDs are promising reagents for blood fingerprints development on non-porous dark surfaces.
Water-soluble fluorescent CdSe quantum dots(QDs) were synthesized using thiolglycolic acid(TGA) as the stabilizer and characterized by fluorescence spectroscopy.The material exhibited strong visible fluorescence under excitation at 365 nm.QDs were applied to label blood fingerprints deposited on non-porous surfaces.Then fluorescent images of fingerprints were obtained by the charge-coupled device(CCD) camera.The effects of labeling time,blood concentration and stored time of blood fingerprints on imaging were investigated.The results showed that the fluorescent images could be obtained within labeling time of 30 min.CdSe QDs can detect blood fingerprints on different surfaces especially on black surface;1% diluted blood fingerprints also could be labeled.The labeled blood fingerprints have higher and stable fluorescence intensity,weaker background interference and better contrast between fingerprints and substrate.CdSe QDs are promising reagents for blood fingerprints development on non-porous dark surfaces.
2011, 28(6): 695-698
doi: 10.3724/SP.J.1095.2011.00388
Abstract:
Pu exists in four different oxidation states(Ⅲ,Ⅳ,Ⅴ,Ⅵ) with in the Eh(Redox Potential) and pH ranges of natural environment.Pu(Ⅳ) in Pu(OH)4 form and Pu(Ⅴ) in PuO2(H2O)n+ form are the dominant oxidation states under equilibrium conditions for groundwater compositions.The sorption distribution coefficients(Kd) of Pu(Ⅳ) and Pu(Ⅴ) in the sand soil were studied by batch experiments,Kd of Pu(Ⅳ) is about 5.5×103 mL/g to 4×104 mL/g,Kd of Pu(Ⅴ) is 3.2×103 mL/g to 1.1×104 mL/g.In conclusion,Kd values of Pu(Ⅳ) in the sand soil were larger than those of Pu(Ⅴ).Such distribution coefficients increase with the increase of amount of clay in sand soil and the decrease of particle size.
Pu exists in four different oxidation states(Ⅲ,Ⅳ,Ⅴ,Ⅵ) with in the Eh(Redox Potential) and pH ranges of natural environment.Pu(Ⅳ) in Pu(OH)4 form and Pu(Ⅴ) in PuO2(H2O)n+ form are the dominant oxidation states under equilibrium conditions for groundwater compositions.The sorption distribution coefficients(Kd) of Pu(Ⅳ) and Pu(Ⅴ) in the sand soil were studied by batch experiments,Kd of Pu(Ⅳ) is about 5.5×103 mL/g to 4×104 mL/g,Kd of Pu(Ⅴ) is 3.2×103 mL/g to 1.1×104 mL/g.In conclusion,Kd values of Pu(Ⅳ) in the sand soil were larger than those of Pu(Ⅴ).Such distribution coefficients increase with the increase of amount of clay in sand soil and the decrease of particle size.
2011, 28(6): 699-703
doi: 10.3724/SP.J.1095.2011.00445
Abstract:
Amino-hydrotalcite like compound(Mg/Al-NH2-HTLc) was prepared by Mg/Al-hydrotalcite like compounds by intercalating sodium dodecyl sulfate(Mg/Al-SDS-HTLc) followed by condensation reactions with hexadecyltrimethyl ammonium bromide(CTAB) and(3-aminopropyl) triethoxysilane(APS).Then,it was used to modify graphite electrode for the adsorption of Escherichia Coli(E.coli).Cyclic voltammetry(CV) was used to investigate the disinfection of the modified electrode.The result showed that the germicidal efficiency could reach to 98.68% and the possible disinfection mechanism might be the oxidation of the substance(such as guanine) within the membrane of E.coli.
Amino-hydrotalcite like compound(Mg/Al-NH2-HTLc) was prepared by Mg/Al-hydrotalcite like compounds by intercalating sodium dodecyl sulfate(Mg/Al-SDS-HTLc) followed by condensation reactions with hexadecyltrimethyl ammonium bromide(CTAB) and(3-aminopropyl) triethoxysilane(APS).Then,it was used to modify graphite electrode for the adsorption of Escherichia Coli(E.coli).Cyclic voltammetry(CV) was used to investigate the disinfection of the modified electrode.The result showed that the germicidal efficiency could reach to 98.68% and the possible disinfection mechanism might be the oxidation of the substance(such as guanine) within the membrane of E.coli.
2011, 28(6): 704-708
doi: 10.3724/SP.J.1095.2011.00431
Abstract:
A carbon paste electrode used as the working electrode,the electrochemical behavior of erythromycin ethylsuccinate(EEs) was investigated by cyclic voltammetry(CV) and differential pulse voltammetry(DPV),a novel method was proposed for the determination of EEs.The results showed two irreversible anodic peaks appeared at 0.83 V and 0.97 V,respectively in 0.1 mol/L PBS buffer solution(pH=8.0),indicating that there were two-step irreversible oxidations.Quantitative measurements by chronoamperometry(I-t) showed that the peak currents were proportional to erythromycin ethylsuccinate concentration in the range of 2.0×10-7~2.8×10-6 and 2.8×10-6~3.1×10-5 mol/L,respectively,with the detection limit(S/N=3) of 1.0×10-7 mol/L.The recovery was in the range of 95.0%~98.8% with a RSD of 3.4%(n=3).The method showed a high selectivity and sensitivity,and could be used for the determination of EEs in the drugs with satisfactory result.
A carbon paste electrode used as the working electrode,the electrochemical behavior of erythromycin ethylsuccinate(EEs) was investigated by cyclic voltammetry(CV) and differential pulse voltammetry(DPV),a novel method was proposed for the determination of EEs.The results showed two irreversible anodic peaks appeared at 0.83 V and 0.97 V,respectively in 0.1 mol/L PBS buffer solution(pH=8.0),indicating that there were two-step irreversible oxidations.Quantitative measurements by chronoamperometry(I-t) showed that the peak currents were proportional to erythromycin ethylsuccinate concentration in the range of 2.0×10-7~2.8×10-6 and 2.8×10-6~3.1×10-5 mol/L,respectively,with the detection limit(S/N=3) of 1.0×10-7 mol/L.The recovery was in the range of 95.0%~98.8% with a RSD of 3.4%(n=3).The method showed a high selectivity and sensitivity,and could be used for the determination of EEs in the drugs with satisfactory result.
2011, 28(6): 709-715
doi: 10.3724/SP.J.1095.2011.00453
Abstract:
The thermal decomposition process of stavudine(STVD) was studied by means of thermogravimetry(TG),differential scanning calorimetry(DSC) and the infrared spectra of STVD.The molecular bond orders were calculated by using GAMESS method of quantum chemistry and the thermal decomposition mechanism of STVD was discussed.The parameters of thermal decomposition kinetics,such as activation energy Ea and preexponential factor A,were obtained by using Ozawa method.The expected lifetimes of STVD at different temperature were estimated using Dakin equation.The results indicated that the thermal decomposition of STVD was a three-stage process.Disconnection of the C-N bond between thymine ring and penta-atomic ring was the first decomposition step.Under nitrogen atmosphere,the temperature range of this first stage is from 139℃ to 173℃,in which the mass loss is 21.2% while Ea and A are 168.9 kJ/mol and 2.884×1019 min-1,respectively.The second thermal decomposition stage is from 173℃ to 313℃ with mass loss of 56.2%,Ea of 96.4 kJ/mol and A of 2.884×108 min-1.The decomposition rate of the third stage is very slow,but still has 10.9% remaining at 800℃.When decomposed under air atmosphere,the temperature range,the mass loss,Ea and A are from 139℃ to 166℃,19.1%,168.1 kJ/mol and 2.188×1019 min-1 for the first decomposition stage are from 166℃ to 314℃,53.9%,154.9 kJ/mol and 8.913×1013 min-1 for the second decomposition stage are from 314℃ to 550℃,27%,116.9 kJ/mol and 3.548×108 min-1 for the third decomposition stage.Accordingly,STVD was quite thermally stable under ambient temperature.
The thermal decomposition process of stavudine(STVD) was studied by means of thermogravimetry(TG),differential scanning calorimetry(DSC) and the infrared spectra of STVD.The molecular bond orders were calculated by using GAMESS method of quantum chemistry and the thermal decomposition mechanism of STVD was discussed.The parameters of thermal decomposition kinetics,such as activation energy Ea and preexponential factor A,were obtained by using Ozawa method.The expected lifetimes of STVD at different temperature were estimated using Dakin equation.The results indicated that the thermal decomposition of STVD was a three-stage process.Disconnection of the C-N bond between thymine ring and penta-atomic ring was the first decomposition step.Under nitrogen atmosphere,the temperature range of this first stage is from 139℃ to 173℃,in which the mass loss is 21.2% while Ea and A are 168.9 kJ/mol and 2.884×1019 min-1,respectively.The second thermal decomposition stage is from 173℃ to 313℃ with mass loss of 56.2%,Ea of 96.4 kJ/mol and A of 2.884×108 min-1.The decomposition rate of the third stage is very slow,but still has 10.9% remaining at 800℃.When decomposed under air atmosphere,the temperature range,the mass loss,Ea and A are from 139℃ to 166℃,19.1%,168.1 kJ/mol and 2.188×1019 min-1 for the first decomposition stage are from 166℃ to 314℃,53.9%,154.9 kJ/mol and 8.913×1013 min-1 for the second decomposition stage are from 314℃ to 550℃,27%,116.9 kJ/mol and 3.548×108 min-1 for the third decomposition stage.Accordingly,STVD was quite thermally stable under ambient temperature.
2011, 28(6): 716-721
doi: 10.3724/SP.J.1095.2011.00438
Abstract:
Three kinds of sulfo-butane betaines(SBm-4) are characterized by FT-IR,1H NMR and elemental analysis.Surface property,foaming property and emulsifying property of these compounds are studied.The results show that the critical micelle concentration(cmc) for SB12-4 is 2.20×10-3 mol/L,γcmc is 31.48 mN/m;while the cmc for SB14-4 is 2.80×10-4 mol/L,γcmc is 29.68 mN/m;and the cmc for SB16-4 is 2.30×10-5 mol/L,γcmc is 32.06 mN/m.The cmc decreases for the three kinds of sulfo-butane betaines as the alkyl chain length increases,while γcmc first decreases and then increases.As the mass concentration of three kinds of surfactants raised,the foaming power increased firstly,and reached to a certain value essentially unchanged.The foam stability was enhanced gradually with increasing the concentration.As the temperature increased,the foaming power was heightened slowly,while foam stability decreased.As the concentration was increased,the emulsifying power of three kinds of surfactants increased firstly and then decreased.
Three kinds of sulfo-butane betaines(SBm-4) are characterized by FT-IR,1H NMR and elemental analysis.Surface property,foaming property and emulsifying property of these compounds are studied.The results show that the critical micelle concentration(cmc) for SB12-4 is 2.20×10-3 mol/L,γcmc is 31.48 mN/m;while the cmc for SB14-4 is 2.80×10-4 mol/L,γcmc is 29.68 mN/m;and the cmc for SB16-4 is 2.30×10-5 mol/L,γcmc is 32.06 mN/m.The cmc decreases for the three kinds of sulfo-butane betaines as the alkyl chain length increases,while γcmc first decreases and then increases.As the mass concentration of three kinds of surfactants raised,the foaming power increased firstly,and reached to a certain value essentially unchanged.The foam stability was enhanced gradually with increasing the concentration.As the temperature increased,the foaming power was heightened slowly,while foam stability decreased.As the concentration was increased,the emulsifying power of three kinds of surfactants increased firstly and then decreased.
2011, 28(6): 722-726
doi: 10.3724/SP.J.1095.2011.00464
Abstract:
A new kind of anionic trisiloxane surfactant(ATSS) was synthesized by the ring-opening reaction of maleic anhydride(MA) with hydroxyl terminated polyether group trisiloxane(HPETS).HPETS was prepared by hydrosilylation from 1,1,1,3,5,5,5-heptamethyltrisiloxane(MDHM) and allyl polyoxyethylene ether(APE) in the presence of platinum catalyst.The chemical structure of ATSS was characterized by IR.The interfacial properties of ATSS were measured,and its application was investigated in pesticide.Experimental results show that ATSS exhibits excellent surface activity.The critical micelle concentration(cmc) of ATSS solution is 1.3 g/L.The surface tension(γcmc) of ATSS solution in cmc is 24.5 mN/m.When ATSS was respectively added with 0.1% into emamectin benzoate 2.5% EC,glyphosate isopropylamin 41% AS and thiophanatemethyl 36% SC diluted to 1000 times with water,the surface tension of emamectin benzoate solution,glyphosate isopropylamin solution and thiophanate-methyl solution was decreased respectively from 31.92 mN/m,55.20 mN/m and 39.66 mN/m to 24.92 mN/m,25.47 mN/m and 27.13 mN/m;while the contact angle on potherb spinach leaf was reduced respectively from 62.5°,68.0° and 57.0° to 37.0°,39.0° and 40.5°.
A new kind of anionic trisiloxane surfactant(ATSS) was synthesized by the ring-opening reaction of maleic anhydride(MA) with hydroxyl terminated polyether group trisiloxane(HPETS).HPETS was prepared by hydrosilylation from 1,1,1,3,5,5,5-heptamethyltrisiloxane(MDHM) and allyl polyoxyethylene ether(APE) in the presence of platinum catalyst.The chemical structure of ATSS was characterized by IR.The interfacial properties of ATSS were measured,and its application was investigated in pesticide.Experimental results show that ATSS exhibits excellent surface activity.The critical micelle concentration(cmc) of ATSS solution is 1.3 g/L.The surface tension(γcmc) of ATSS solution in cmc is 24.5 mN/m.When ATSS was respectively added with 0.1% into emamectin benzoate 2.5% EC,glyphosate isopropylamin 41% AS and thiophanatemethyl 36% SC diluted to 1000 times with water,the surface tension of emamectin benzoate solution,glyphosate isopropylamin solution and thiophanate-methyl solution was decreased respectively from 31.92 mN/m,55.20 mN/m and 39.66 mN/m to 24.92 mN/m,25.47 mN/m and 27.13 mN/m;while the contact angle on potherb spinach leaf was reduced respectively from 62.5°,68.0° and 57.0° to 37.0°,39.0° and 40.5°.
2011, 28(6): 727-732
doi: 10.3724/SP.J.1095.2011.00527
Abstract:
In order to understand the effect of Ti on the carbides and topologically close-packed phases(TCP) in a high-temperature cast nickel-based superalloy,samples with different Ti content after heat treatment and different aging time were investigated by optical microscopy(OM),scanning electron microscopy(SEM) and transmission electron microscopy(TEM).The results show that the microstructures of as-heated alloy with different Ti content are the same and all are composed of γ,γ',MC,and M23C6 carbides.With increasing Ti amount in the alloy,the volume fraction of carbides gradually increased.The carbide is mainly TaC when there is no Ti in the alloy,and the carbide gradually changes to(Ta,Ti) C with the addition of Ti.By examining the microstructures of alloys aged at 900℃ for different time,it has been found that the TCP segregated easily after addition of Ti in alloy.When the alloy with 2.7% mass fraction of Ti aged at 900℃ for 500 h,it shows that the σ phase contains a lot of Cr,W and Mo,indicating that it is necessary to control the amount of Ti in order to obtain an excellent phase stability of the alloy.
In order to understand the effect of Ti on the carbides and topologically close-packed phases(TCP) in a high-temperature cast nickel-based superalloy,samples with different Ti content after heat treatment and different aging time were investigated by optical microscopy(OM),scanning electron microscopy(SEM) and transmission electron microscopy(TEM).The results show that the microstructures of as-heated alloy with different Ti content are the same and all are composed of γ,γ',MC,and M23C6 carbides.With increasing Ti amount in the alloy,the volume fraction of carbides gradually increased.The carbide is mainly TaC when there is no Ti in the alloy,and the carbide gradually changes to(Ta,Ti) C with the addition of Ti.By examining the microstructures of alloys aged at 900℃ for different time,it has been found that the TCP segregated easily after addition of Ti in alloy.When the alloy with 2.7% mass fraction of Ti aged at 900℃ for 500 h,it shows that the σ phase contains a lot of Cr,W and Mo,indicating that it is necessary to control the amount of Ti in order to obtain an excellent phase stability of the alloy.
