Micellar and microemulsion electrokinetic chromatography (MEKC & MEEKC) separation of six closely structural pyridoncarboylxic acid derivatives were studied and compared. Both anionic surfactant sodium dodecyl sul...Micellar and microemulsion electrokinetic chromatography (MEKC & MEEKC) separation of six closely structural pyridoncarboylxic acid derivatives were studied and compared. Both anionic surfactant sodium dodecyl sulfate (SDS) and cationic surfactant hexadecyl-trimethyl ammonium bromide (CTAB) were used to form micellar and microemulsion as pseudostation phases, respectively. The effects of the separation conditions on retention time and selectivity were studied. Good resolutions were obtained in selected systems, indicating that there is markably different selectivity between SDS and CTAB systems.展开更多
Reducing the oil-water interfacial tension(IFT)to ultra-low is believed the primary mechanism for surfactant-based enhanced oil recovery(EOR)process.However,field trials have shown that low concentration surfactant fl...Reducing the oil-water interfacial tension(IFT)to ultra-low is believed the primary mechanism for surfactant-based enhanced oil recovery(EOR)process.However,field trials have shown that low concentration surfactant flooding can also improve oil recovery without ultra-low IFT.To clarify the mechanism behind,the currently-used surfactant,naphthenic arylsulfonate(NAS),was used to unravel its function during surfactant flooding from the horizon of micron-and nano-scale.The solubilization capacity of NAS micelle to petroleum fractions was evaluated through light absorbance strategy,smallangle neutron scattering,dynamic light scattering and transmission electron microscopy.It was found that micellar solubilization plays a significant role during the surfactant flooding.In-situ emulsification was visualized in microfluidics with three types of microchips,respectively.A series of displacement tests were carried out with NAS solution pumping into oil-saturated chip.The results show that in-situ emulsification improve oil recovery mainly through blocking and entrainment effects.Results from this work aid in understanding the interaction between surfactant solution and petroleum fractions at low surfactant concentration,which is helpful for design surfactant-based displacing system for EOR process.展开更多
High-quality mesoporous silica MCM-48 were synthesized under basic conditions by using the mixture of cetyltrimethylammonium bromide (CTAB) and alkylamine (CnNH2n+3, n=8,10,12,14, respectively) as templates. The effec...High-quality mesoporous silica MCM-48 were synthesized under basic conditions by using the mixture of cetyltrimethylammonium bromide (CTAB) and alkylamine (CnNH2n+3, n=8,10,12,14, respectively) as templates. The effects of the alkylamines with different chain lengths (n=8,10,12,14,16,18, respectively) on the silica structure were investigated.展开更多
Ganoderma(lingzhi)is a famous herbal medicine and edible supplement in oriental countries for a long history.In this study,a simple micellar electrokinetic chromatography(MEKC)method was established for the analysis o...Ganoderma(lingzhi)is a famous herbal medicine and edible supplement in oriental countries for a long history.In this study,a simple micellar electrokinetic chromatography(MEKC)method was established for the analysis of nucleosides and bases,the major bioactive components in Ganoderma for the first time.By optimizing the borate concentration,the sodium dodecyl sulfate(SDS)concentration and the pH value of running buffer,10 nucleosides and bases achieved an ideal separation.In real sample analysis,the developed method was successfully used to determine the 10 target analytes in 23 batches of Ganoderma samples from different regions.Results indicated that contents of 10 investigated analytes in each sample showed obvious variation.The principal components analysis(PCA)and hierarchical cluster analysis(HCA)analysis classified the samples into three groups,and the HCA tree visualized the relationships which was mainly contributed by geographical partition.The results indicated geographical origin to be an important factor that affect the accumulation of nucleosides and bases in Ganoderma.In summary,this study provides a simple and practical strategy for quality assessment and cultivation reference of Ganoderma.展开更多
Biopartitioning micellar chromatography(BMC)is a potentially high throughput and low cost alternative for in vitro prediction of drug absorption,which can mimic the drug partitioning process in biological systems.In t...Biopartitioning micellar chromatography(BMC)is a potentially high throughput and low cost alternative for in vitro prediction of drug absorption,which can mimic the drug partitioning process in biological systems.In this paper,a data set of 56 compounds representing acidic,basic,neutral and amphoteric drugs from various structure classes with human oral absorption(HOA)data available were employed to show the effect of acidity of drugs in oral absorption prediction.HOA was reciprocally correlated to the negative value of the capacity factor(kBMC)determined by BMC at pH 7.4 and 6.5.The relationships between kBMC and the corresponding HOA values of all compounds were rather poor,but the correlations were improved when the acidity of drugs was taken into consideration.Moreover,the proposed models allowed obtaining of good predictive values for both highly and poorly absorbed compounds.It is demonstrated that the constructed models derived from compounds with the same kind of charge property are of more practically meaningful and rigorous.展开更多
An efficient and greener protocol for the synthesis of 1-halo-naphthols by the action of hydrogen peroxide and alkali metal halides in aqueous micellar media is been described in the present work. This is an environme...An efficient and greener protocol for the synthesis of 1-halo-naphthols by the action of hydrogen peroxide and alkali metal halides in aqueous micellar media is been described in the present work. This is an environmentally clean and safe procedure, which involved insitu generation of the active halogen in presence of alkali halides. Cationic surfactants such as cetyltrimethylammoniumbromide (CTAB) and cetyltrimethylammoniumchloride (CTAC) were found to facilitate efficiency of halogenation in aqueous media.展开更多
To separate cadmium ions from aqueous solution efficiently, micellar-enhanced ultrafiltration(MEUF) of hollow ultrafiltration membrane was used, with sodium dodecyl benzene sulfonate (SDBS) and sodium dodecyl (sulfate...To separate cadmium ions from aqueous solution efficiently, micellar-enhanced ultrafiltration(MEUF) of hollow ultrafiltration membrane was used, with sodium dodecyl benzene sulfonate (SDBS) and sodium dodecyl (sulfate) (SDS) as surfactants. The important parameters affecting the rejection of cadmium, the permeate flux and the secondary resistance were investigated, including surfactant species, surfactant concentration, operating time, trans-membrane pressure, the addition of electrolyte and solution pH. The results show that the rejection rate of cadmium reaches 97.8%. Trans-membrane pressure and the addition of electrolyte (NaCl) are less influential while surfactant species, surfactant concentration and pH value are important for micellar-enhanced ultrafiltration. The optimum concentration of surfactant is the critical micelle concentration, and SDBS is better than SDS. (Micellar-)(enhanced) ultrafiltration with SDBS can separate cadmium ions from aqueous solution efficiently.展开更多
Enantiomeric separation of epinephrine and salbutamol was investigated by micellar electrokinetic chromatography employing β-cyclodextrin as chiral additive in ammonium chloride-ammonia solution. The analytes were de...Enantiomeric separation of epinephrine and salbutamol was investigated by micellar electrokinetic chromatography employing β-cyclodextrin as chiral additive in ammonium chloride-ammonia solution. The analytes were detected by electrochemistry using gold microelectrode at +0.65 V versus SCE reference electrode. The effects of detection potential, concentration of β-cyclodextrin, concentration of sodium dodecyl sulfate, pH value of electrolyte and applied voltage were discussed.展开更多
A simple and selective micellar electrokinetic chromatographic (MEKC) method has been developed for the analysis of five pharmaceutical binary mixtures containing three non-steroidal anti- inflammatory drugs (NSAIDs)....A simple and selective micellar electrokinetic chromatographic (MEKC) method has been developed for the analysis of five pharmaceutical binary mixtures containing three non-steroidal anti- inflammatory drugs (NSAIDs). The investigated mixtures were Ibuprofen (IP)-Paracetamol (PC), Ibuprofen (IP)-Chlorzoxazone (CZ), Ibuprofen (IP)-Methocarbamol (MC), Ketoprofen (KP)-Chlorzoxazone (CZ) and Diclofenac sodium (DS)-Lidocaine hydrochloride (LC). The separation was run for all mixtures using borate buffer (20 mM, pH 9) containing 15% (v/v) methanol and 100 mM sodium dodecyl sulphate (SDS) at 15 kV and the components were detected at 214 nm. Different factors affecting the electrophoretic mobility of the seven investigated drugs were studied and optimized. The method was validated according to international conference of harmonization (ICH) guidelines and United States pharmacopoeia (USP). The method was applied to the analysis of five pharmaceutical binary mixtures in their dosage forms. The results were compared with other reported high performance liquid chromatographic methods and no significant differences were observed.展开更多
The origin of pseudo peak was studied by means of micellar electrokinetic capillary chromatography with cetyltrimethylaminium bromide as the pseudo stationary phase. It has been pointed that two peaks may appear for o...The origin of pseudo peak was studied by means of micellar electrokinetic capillary chromatography with cetyltrimethylaminium bromide as the pseudo stationary phase. It has been pointed that two peaks may appear for one component under certain conditions. Experiments showed that the relative areas of the two peaks of analyte depended on the time and the temperature of reaction between analyte and surfactant, and the concentration of surfactant in the sample solution. It means that the interaction between the analyte and the surfactant is a slow process, and a stable substance can be produced from the interaction. It is the substance and the analyte that may lead to the formation of two peaks. The fast interaction mechanism between the solute and the micellar should be queried from the experiment result.展开更多
To separate zinc ions from aqueous solution efficiently, micellar-enhanced ultrafiltration(MEUF) of hollow ultrafiltration membrane was used with sodium dodecyl sulfate(SDS) as surfactant.The formation of micellar and...To separate zinc ions from aqueous solution efficiently, micellar-enhanced ultrafiltration(MEUF) of hollow ultrafiltration membrane was used with sodium dodecyl sulfate(SDS) as surfactant.The formation of micellar and the adsorption mechanism were investigated, including the influence of the ratio of SDS to zinc ions on the micelle quantity, the micelle ratio, the gross adsorptive capacity, the rejection of zinc ions and the adsorption isotherm law. The results show that the rejection rate of zinc ions reaches 97% and the adsorption of zinc ions on SDS conforms to the Langmuir adsorption isotherm and the adsorption is a chemical adsorption process.展开更多
An amphiphilic porphyrin, 5, 10, 15, 20-tetra(4-hydroxyphenyl)-porphyrin (P) was solubilized in SDS micellar solutions. By taking advantage of protonation property of pyridine groups of amphiphilic porphyrin and the U...An amphiphilic porphyrin, 5, 10, 15, 20-tetra(4-hydroxyphenyl)-porphyrin (P) was solubilized in SDS micellar solutions. By taking advantage of protonation property of pyridine groups of amphiphilic porphyrin and the UV-Vis spectral sensitivity of Soret band and Q bands to the microenvironment of the porphyrin moiety, two-step protonation was studied in detail by means of UV-Vis spectroscopy. The free base, monocation and dication were described in detail in SDS micellar solution. The possibility of microphase transition was proposed to relate to the observation of two isosbestic points.展开更多
A flow injection method is proposed for determining vanadium(V). The method is based on its catalytic effect on the oxidation of malachite green oxalate by bromate. The reaction was monitored spectrophotometrically by...A flow injection method is proposed for determining vanadium(V). The method is based on its catalytic effect on the oxidation of malachite green oxalate by bromate. The reaction was monitored spectrophotometrically by measuring malachite green oxalate absorbance at λmax = 625 nm. The reagents and manifold variables, which have influences on the sensitivity, were investigated and the optimum conditions were established. The optimized conditions made it possible to determine vanadium in the ranges of 10-140 ng/mL with a detection limit of 5.2 ng/mL and a sample rate of 20 ± 5 samples/h.展开更多
A simple,eco-friendly.sensitive and economic flow injection spectrofluorimetric method was developed for the determination of O-(β-hydroxyethyl)rutosidcs.The procedure was based on the use of an anionic surfactant su...A simple,eco-friendly.sensitive and economic flow injection spectrofluorimetric method was developed for the determination of O-(β-hydroxyethyl)rutosidcs.The procedure was based on the use of an anionic surfactant such as sodium dodecyl sulfate to provide an appreciable O-(β-hydroxyethyl)rutosides fluorescence enhancement,increasing considerably the sensitivity of detection.All the variables affecting the fluorescence intensity were studied and optimized.The flow rate was 5 mL/min with detection at 450 nm(after excitation at 346 nm).A linear correlation between drug amount and peak area was established for 0-(β-hydroxyethyl)rulosides in the range of 0.01-200 μg/mL with a detection limit of0.001 μg/mL(s/n = 3).Validation processes were performed by recovering studies with satisfactory results.The new methodology can be employed for the routine analysis of 0-(P-hydroxyethyl)rutosides in bulks as well as in commercial formulations.展开更多
A micellar electrokinetic capillary chromatography (MECC) was developed for the determination of aniline and 6 substituted anilines. The seven components were separated within 25min in the buffer solution of 40mmol/L ...A micellar electrokinetic capillary chromatography (MECC) was developed for the determination of aniline and 6 substituted anilines. The seven components were separated within 25min in the buffer solution of 40mmol/L sodium borate and 100mmol/L SDS. It was found that the separation was dependent on operating voltage, pH value, borate and SDS concentrations.The analytical performance was examined in terms of linear response and reproducibility.Wastewater was determined by the established method.展开更多
[Objective] To investigate the factors affecting sesame residue protein extraction and find the optimum extraction conditions.[Method] Sesame residue proteins were extracted with bis(2-ethylhexyl)sulfosuccinate(AOT)/i...[Objective] To investigate the factors affecting sesame residue protein extraction and find the optimum extraction conditions.[Method] Sesame residue proteins were extracted with bis(2-ethylhexyl)sulfosuccinate(AOT)/isooctane reverse micellar system.Orthogonal test was used to screen the optimum combination of four factors including sesame residue concentration,pre-extraction pH value,potassium chloride concentration and reverse extraction time.The yield of extracted sesame residue proteins was the indicator to evaluate the efficiency of process.[Result] The optimum extraction conditions are as follows:sesame residue concentration:0.06 g/ml;pre-extraction pH value,3.0;potassium chloride concentration,1.5 mol/L;and reverse extraction time,20 min.In the optimum extraction conditions,the extraction rate was up to 86%.[Conclusion] Extraction of sesame residue proteins can be well performed with AOT/isooctane reverse micellar system.展开更多
The cleavage of DNA (pUC18) by lipophilic macrocyclic polyamine Co(II) complex was investigated in metallomicellar system. The results showed that the conversion of plasmid DNA (pUC18) increases with the increase of t...The cleavage of DNA (pUC18) by lipophilic macrocyclic polyamine Co(II) complex was investigated in metallomicellar system. The results showed that the conversion of plasmid DNA (pUC18) increases with the increase of the concentration of complex under physiological conditions.展开更多
基金the National Natural Science Foundation of China.
文摘Micellar and microemulsion electrokinetic chromatography (MEKC & MEEKC) separation of six closely structural pyridoncarboylxic acid derivatives were studied and compared. Both anionic surfactant sodium dodecyl sulfate (SDS) and cationic surfactant hexadecyl-trimethyl ammonium bromide (CTAB) were used to form micellar and microemulsion as pseudostation phases, respectively. The effects of the separation conditions on retention time and selectivity were studied. Good resolutions were obtained in selected systems, indicating that there is markably different selectivity between SDS and CTAB systems.
基金Natural Science Foundation of China for its financial support(grant number:U1762218)
文摘Reducing the oil-water interfacial tension(IFT)to ultra-low is believed the primary mechanism for surfactant-based enhanced oil recovery(EOR)process.However,field trials have shown that low concentration surfactant flooding can also improve oil recovery without ultra-low IFT.To clarify the mechanism behind,the currently-used surfactant,naphthenic arylsulfonate(NAS),was used to unravel its function during surfactant flooding from the horizon of micron-and nano-scale.The solubilization capacity of NAS micelle to petroleum fractions was evaluated through light absorbance strategy,smallangle neutron scattering,dynamic light scattering and transmission electron microscopy.It was found that micellar solubilization plays a significant role during the surfactant flooding.In-situ emulsification was visualized in microfluidics with three types of microchips,respectively.A series of displacement tests were carried out with NAS solution pumping into oil-saturated chip.The results show that in-situ emulsification improve oil recovery mainly through blocking and entrainment effects.Results from this work aid in understanding the interaction between surfactant solution and petroleum fractions at low surfactant concentration,which is helpful for design surfactant-based displacing system for EOR process.
基金the State Key Program Foundation of China (97021107)The National Natural Science Foundation of China (29992590-4).
文摘High-quality mesoporous silica MCM-48 were synthesized under basic conditions by using the mixture of cetyltrimethylammonium bromide (CTAB) and alkylamine (CnNH2n+3, n=8,10,12,14, respectively) as templates. The effects of the alkylamines with different chain lengths (n=8,10,12,14,16,18, respectively) on the silica structure were investigated.
基金financially supported by the Research Committee of the University of Macao(MYRG2018-00239-ICMS and MYRG2014-00089-ICMS-QRCM)the Macao Science and Technology Development Fund(162/2017/A3)Guangzhou International Science and Technology Cooperation Project(File no.201807010044)。
文摘Ganoderma(lingzhi)is a famous herbal medicine and edible supplement in oriental countries for a long history.In this study,a simple micellar electrokinetic chromatography(MEKC)method was established for the analysis of nucleosides and bases,the major bioactive components in Ganoderma for the first time.By optimizing the borate concentration,the sodium dodecyl sulfate(SDS)concentration and the pH value of running buffer,10 nucleosides and bases achieved an ideal separation.In real sample analysis,the developed method was successfully used to determine the 10 target analytes in 23 batches of Ganoderma samples from different regions.Results indicated that contents of 10 investigated analytes in each sample showed obvious variation.The principal components analysis(PCA)and hierarchical cluster analysis(HCA)analysis classified the samples into three groups,and the HCA tree visualized the relationships which was mainly contributed by geographical partition.The results indicated geographical origin to be an important factor that affect the accumulation of nucleosides and bases in Ganoderma.In summary,this study provides a simple and practical strategy for quality assessment and cultivation reference of Ganoderma.
文摘Biopartitioning micellar chromatography(BMC)is a potentially high throughput and low cost alternative for in vitro prediction of drug absorption,which can mimic the drug partitioning process in biological systems.In this paper,a data set of 56 compounds representing acidic,basic,neutral and amphoteric drugs from various structure classes with human oral absorption(HOA)data available were employed to show the effect of acidity of drugs in oral absorption prediction.HOA was reciprocally correlated to the negative value of the capacity factor(kBMC)determined by BMC at pH 7.4 and 6.5.The relationships between kBMC and the corresponding HOA values of all compounds were rather poor,but the correlations were improved when the acidity of drugs was taken into consideration.Moreover,the proposed models allowed obtaining of good predictive values for both highly and poorly absorbed compounds.It is demonstrated that the constructed models derived from compounds with the same kind of charge property are of more practically meaningful and rigorous.
文摘An efficient and greener protocol for the synthesis of 1-halo-naphthols by the action of hydrogen peroxide and alkali metal halides in aqueous micellar media is been described in the present work. This is an environmentally clean and safe procedure, which involved insitu generation of the active halogen in presence of alkali halides. Cationic surfactants such as cetyltrimethylammoniumbromide (CTAB) and cetyltrimethylammoniumchloride (CTAC) were found to facilitate efficiency of halogenation in aqueous media.
基金Project (50225926) supported by the National Foundation for Distinguished Young Scholars Project (20020532017)supported by the Doctoral Foundation of Ministry of Education of China Project (2003AA644010) supported by the National High techResear
文摘To separate cadmium ions from aqueous solution efficiently, micellar-enhanced ultrafiltration(MEUF) of hollow ultrafiltration membrane was used, with sodium dodecyl benzene sulfonate (SDBS) and sodium dodecyl (sulfate) (SDS) as surfactants. The important parameters affecting the rejection of cadmium, the permeate flux and the secondary resistance were investigated, including surfactant species, surfactant concentration, operating time, trans-membrane pressure, the addition of electrolyte and solution pH. The results show that the rejection rate of cadmium reaches 97.8%. Trans-membrane pressure and the addition of electrolyte (NaCl) are less influential while surfactant species, surfactant concentration and pH value are important for micellar-enhanced ultrafiltration. The optimum concentration of surfactant is the critical micelle concentration, and SDBS is better than SDS. (Micellar-)(enhanced) ultrafiltration with SDBS can separate cadmium ions from aqueous solution efficiently.
文摘Enantiomeric separation of epinephrine and salbutamol was investigated by micellar electrokinetic chromatography employing β-cyclodextrin as chiral additive in ammonium chloride-ammonia solution. The analytes were detected by electrochemistry using gold microelectrode at +0.65 V versus SCE reference electrode. The effects of detection potential, concentration of β-cyclodextrin, concentration of sodium dodecyl sulfate, pH value of electrolyte and applied voltage were discussed.
文摘A simple and selective micellar electrokinetic chromatographic (MEKC) method has been developed for the analysis of five pharmaceutical binary mixtures containing three non-steroidal anti- inflammatory drugs (NSAIDs). The investigated mixtures were Ibuprofen (IP)-Paracetamol (PC), Ibuprofen (IP)-Chlorzoxazone (CZ), Ibuprofen (IP)-Methocarbamol (MC), Ketoprofen (KP)-Chlorzoxazone (CZ) and Diclofenac sodium (DS)-Lidocaine hydrochloride (LC). The separation was run for all mixtures using borate buffer (20 mM, pH 9) containing 15% (v/v) methanol and 100 mM sodium dodecyl sulphate (SDS) at 15 kV and the components were detected at 214 nm. Different factors affecting the electrophoretic mobility of the seven investigated drugs were studied and optimized. The method was validated according to international conference of harmonization (ICH) guidelines and United States pharmacopoeia (USP). The method was applied to the analysis of five pharmaceutical binary mixtures in their dosage forms. The results were compared with other reported high performance liquid chromatographic methods and no significant differences were observed.
基金Supported by the National Natural Science Foundation of China(No. 2 0 0 75 0 0 5 ) and the Natural Science Foundation ofHebei ProvinceChina(No. 2 0 0 0 77,2 0 2 0 96 )
文摘The origin of pseudo peak was studied by means of micellar electrokinetic capillary chromatography with cetyltrimethylaminium bromide as the pseudo stationary phase. It has been pointed that two peaks may appear for one component under certain conditions. Experiments showed that the relative areas of the two peaks of analyte depended on the time and the temperature of reaction between analyte and surfactant, and the concentration of surfactant in the sample solution. It means that the interaction between the analyte and the surfactant is a slow process, and a stable substance can be produced from the interaction. It is the substance and the analyte that may lead to the formation of two peaks. The fast interaction mechanism between the solute and the micellar should be queried from the experiment result.
基金Project(50608028) supported by the National Natural Science Foundation of ChinaProject(50225926) supported by the National Foundation for Distinguished Young Scholars+2 种基金Project(20020532017) supported by the Doctoral Foundation of Ministry of Education of ChinaProject(2003AA644010) supported by the National High-Tech Research Program of ChinaProject([2005]100) supported by Scientific Research Fund of Hunan Provincial Education Department, China
文摘To separate zinc ions from aqueous solution efficiently, micellar-enhanced ultrafiltration(MEUF) of hollow ultrafiltration membrane was used with sodium dodecyl sulfate(SDS) as surfactant.The formation of micellar and the adsorption mechanism were investigated, including the influence of the ratio of SDS to zinc ions on the micelle quantity, the micelle ratio, the gross adsorptive capacity, the rejection of zinc ions and the adsorption isotherm law. The results show that the rejection rate of zinc ions reaches 97% and the adsorption of zinc ions on SDS conforms to the Langmuir adsorption isotherm and the adsorption is a chemical adsorption process.
文摘An amphiphilic porphyrin, 5, 10, 15, 20-tetra(4-hydroxyphenyl)-porphyrin (P) was solubilized in SDS micellar solutions. By taking advantage of protonation property of pyridine groups of amphiphilic porphyrin and the UV-Vis spectral sensitivity of Soret band and Q bands to the microenvironment of the porphyrin moiety, two-step protonation was studied in detail by means of UV-Vis spectroscopy. The free base, monocation and dication were described in detail in SDS micellar solution. The possibility of microphase transition was proposed to relate to the observation of two isosbestic points.
文摘A flow injection method is proposed for determining vanadium(V). The method is based on its catalytic effect on the oxidation of malachite green oxalate by bromate. The reaction was monitored spectrophotometrically by measuring malachite green oxalate absorbance at λmax = 625 nm. The reagents and manifold variables, which have influences on the sensitivity, were investigated and the optimum conditions were established. The optimized conditions made it possible to determine vanadium in the ranges of 10-140 ng/mL with a detection limit of 5.2 ng/mL and a sample rate of 20 ± 5 samples/h.
基金the National University of San Luis(Project 22/Q228)INQUISAL-CONICET(Instituto de Quimica de San Luis-Consejo Nacional de Investigaciones Cientificas y Tecnicas, PIP-CONICET 11220100100405) for the financial support
文摘A simple,eco-friendly.sensitive and economic flow injection spectrofluorimetric method was developed for the determination of O-(β-hydroxyethyl)rutosidcs.The procedure was based on the use of an anionic surfactant such as sodium dodecyl sulfate to provide an appreciable O-(β-hydroxyethyl)rutosides fluorescence enhancement,increasing considerably the sensitivity of detection.All the variables affecting the fluorescence intensity were studied and optimized.The flow rate was 5 mL/min with detection at 450 nm(after excitation at 346 nm).A linear correlation between drug amount and peak area was established for 0-(β-hydroxyethyl)rulosides in the range of 0.01-200 μg/mL with a detection limit of0.001 μg/mL(s/n = 3).Validation processes were performed by recovering studies with satisfactory results.The new methodology can be employed for the routine analysis of 0-(P-hydroxyethyl)rutosides in bulks as well as in commercial formulations.
文摘A micellar electrokinetic capillary chromatography (MECC) was developed for the determination of aniline and 6 substituted anilines. The seven components were separated within 25min in the buffer solution of 40mmol/L sodium borate and 100mmol/L SDS. It was found that the separation was dependent on operating voltage, pH value, borate and SDS concentrations.The analytical performance was examined in terms of linear response and reproducibility.Wastewater was determined by the established method.
基金supported by the grants from Research Foun-dation of Xuzhou Institute of Technology (XKY2007222)
文摘[Objective] To investigate the factors affecting sesame residue protein extraction and find the optimum extraction conditions.[Method] Sesame residue proteins were extracted with bis(2-ethylhexyl)sulfosuccinate(AOT)/isooctane reverse micellar system.Orthogonal test was used to screen the optimum combination of four factors including sesame residue concentration,pre-extraction pH value,potassium chloride concentration and reverse extraction time.The yield of extracted sesame residue proteins was the indicator to evaluate the efficiency of process.[Result] The optimum extraction conditions are as follows:sesame residue concentration:0.06 g/ml;pre-extraction pH value,3.0;potassium chloride concentration,1.5 mol/L;and reverse extraction time,20 min.In the optimum extraction conditions,the extraction rate was up to 86%.[Conclusion] Extraction of sesame residue proteins can be well performed with AOT/isooctane reverse micellar system.
基金We are thankful to the National Natural Science Foundation of China for financial support (No. 29872027).
文摘The cleavage of DNA (pUC18) by lipophilic macrocyclic polyamine Co(II) complex was investigated in metallomicellar system. The results showed that the conversion of plasmid DNA (pUC18) increases with the increase of the concentration of complex under physiological conditions.
