To simultaneously enrich,separate,and determine five fluoroquinolone antibiotics(FQs)in marine crude drugs(MCDs),seawater and seafood,we conducted this study using vortex assisted dispersed liquid-liquid microextracti...To simultaneously enrich,separate,and determine five fluoroquinolone antibiotics(FQs)in marine crude drugs(MCDs),seawater and seafood,we conducted this study using vortex assisted dispersed liquid-liquid microextraction(DLLME),followed by capillary electrophoresis(CE)-UV.A single-variable optimization was employed to examine the factors influencing the separation effect of CE and the extraction efficiency of DLLME,including buffer solution,organic solvent,separation voltage,extractant,dispersant,and sample solution pH.Under the optimal conditions,the baseline separation of the five FQs was achieved within 6 min.The analytical performance of the method was assessed using six types of actual samples,including three MCDs of hippocampus,clam,and kelp,seawater,and two seafood of prawn and pomfret,demonstrating good linearity ranging from 0.1-5 or 0.01-5μg/mL.The limits of detection(LODs)and limits of quantification(LOQs)for the five FQs in MCDs were 0.0022-0.0292 and 0.0066-0.0973μg/mL,respectively.The LODs and LOQs in seawater and seafood were 0.0009-0.0262 and 0.0029-0.0874μg/mL,respectively.The matrix effects of this method were evaluated in the hippocampus,seawater,and prawn,and the results show that DLLME could effectively eliminate matrix interference.Satisfactory recovery rates were achieved in all the six tested actual samples.This developed DLLME-CE method was proven simple to operate,accurate and reliable,with high sensitivity,making it suitable for the analysis of multiple antibiotic residues in complex matrices.展开更多
The coating material is considered as the key of solid-phase microextraction(SPME)due to the fact that which has much effect on the selectivity and sensitivity of the analytical method.Herein,the porous hollow carbon ...The coating material is considered as the key of solid-phase microextraction(SPME)due to the fact that which has much effect on the selectivity and sensitivity of the analytical method.Herein,the porous hollow carbon nanospheres(PHCNs)were synthesized by selectively removing the interior part of solid inhomogeneous nanospheres with acetone.Using PHCNs as new coating material,a SPME fiber was prepared.To the best of our knowledge,PHCNs was utilized as a SPME fiber coating for the first time.The fiber coating material PHCNs demonstrated excellent thermal stability(>800℃)and long usage lifespan(≥60 times).A headspace SPME(HS-SPME)was established to non-contact extract and enrich polycyclic aromatic hydrocarbons(PAHs)prior to gas chromatography-flame ionization detector(GC-FID)analysis.The HS-SPME not only can eliminate non-volatile interferences from matrix,but also be able to protect fiber coating and prolong lifespan of fiber prober.The linearity in the linear range of 0.01-30 ng/m L and limits of detection from 0.003 ng/mL to 0.006 ng/mL were obtained by HS-SPME-GC-FID with PHCNs as fiber coating.The enrichment factors were calculated as 5420-9211 compared with conventional direct introduce analysis.The spiked recoveries of real samples including campus lake water and lime tree honey were obtained from 80.93%to 118.0%with relative standard deviation no higher than 10.6%.The π-π stacking interaction,CH/π interaction,and unique built-in cavities significantly enhance the extraction performance of PHCNs coating fiber to PAHs.This work demonstrated that the PHCNs as fiber coating materials present good application prospects for the extraction and enrichment of trace PAHs from complex matrixes.展开更多
采用高密度疏水性低共熔溶剂(Hydrophobic Deep Eutectic Solvents,HDESs)为萃取剂,结合分光光度法,建立了一种涡旋辅助-液相微萃取技术,并成功应用于水中亚甲基蓝的快速测定。HDESs由薄荷醇(氢键受体)和对氯苯酚(氢键供体)按1:1的摩尔...采用高密度疏水性低共熔溶剂(Hydrophobic Deep Eutectic Solvents,HDESs)为萃取剂,结合分光光度法,建立了一种涡旋辅助-液相微萃取技术,并成功应用于水中亚甲基蓝的快速测定。HDESs由薄荷醇(氢键受体)和对氯苯酚(氢键供体)按1:1的摩尔比合成,具有优异的疏水性、高密度特性和对亚甲基蓝的较高亲和力。系统考察了萃取剂的种类和用量、涡旋时间及pH值等关键参数对亚甲基蓝萃取效果的影响。在最佳萃取条件(HDESs用量100μL,pH=8,涡旋时间90 s)下,平均加标回收率为89.83%~102.3%,相对标准偏差RSD≤7.58%。该方法在亚甲基蓝的实际水样分析中具有较高的准确性和实用性。展开更多
The chlorination process is one of the water treatment method used for the disinfection of water. The disinfection by products are trihalomethanes such as chloroform, dichloromethane, dibromochloromethane and bromofor...The chlorination process is one of the water treatment method used for the disinfection of water. The disinfection by products are trihalomethanes such as chloroform, dichloromethane, dibromochloromethane and bromoform. A headspace solid-phase microextraction method has been developed for determination oftrihalomethanes in water samples. The experimental parameters such as the stirring rate, extraction time, extraction temperature and desorption time were investigated. The linearity, detection limits and percentage recovery were evaluated. The optimum conditions were stirring rate 800 rpm/min, extraction time 6 min, extraction temperature 20 ~C, desorption time 2.5 min and desorption temperature 220 ~C. The detection limits were 0.01 ~g/L and the recoveries were in the range of 86-110 %, The proposed method was successfully applied to determination of THM4 in tap water samples. The THM4 contents were varied depending on the sample sites and the season. The total THM4 contents in cool, summer and rainy season were in the range of 27.58-41.89, 32.06-60.73 and 46.26-69.87 p.g/L, respectively. Confirmation of the detected compounds in water samples were performed by gas chromatograph-mass spectrometer. The mass spectra of the target compounds in water samples is in good agreement with trihalomethanes standard spectra.展开更多
基金Supported by the National Natural Science Foundation of China(No.22176210)the Major Innovation Fund of Shandong Province(No.2021ZDSYS23)。
文摘To simultaneously enrich,separate,and determine five fluoroquinolone antibiotics(FQs)in marine crude drugs(MCDs),seawater and seafood,we conducted this study using vortex assisted dispersed liquid-liquid microextraction(DLLME),followed by capillary electrophoresis(CE)-UV.A single-variable optimization was employed to examine the factors influencing the separation effect of CE and the extraction efficiency of DLLME,including buffer solution,organic solvent,separation voltage,extractant,dispersant,and sample solution pH.Under the optimal conditions,the baseline separation of the five FQs was achieved within 6 min.The analytical performance of the method was assessed using six types of actual samples,including three MCDs of hippocampus,clam,and kelp,seawater,and two seafood of prawn and pomfret,demonstrating good linearity ranging from 0.1-5 or 0.01-5μg/mL.The limits of detection(LODs)and limits of quantification(LOQs)for the five FQs in MCDs were 0.0022-0.0292 and 0.0066-0.0973μg/mL,respectively.The LODs and LOQs in seawater and seafood were 0.0009-0.0262 and 0.0029-0.0874μg/mL,respectively.The matrix effects of this method were evaluated in the hippocampus,seawater,and prawn,and the results show that DLLME could effectively eliminate matrix interference.Satisfactory recovery rates were achieved in all the six tested actual samples.This developed DLLME-CE method was proven simple to operate,accurate and reliable,with high sensitivity,making it suitable for the analysis of multiple antibiotic residues in complex matrices.
基金supported by National Natural Science Foundation of China(No.22376053)supported by the Natural Science Foundation of Henan Province,China(No.242300421034)Henan Key Scientific Research Programs to Universities and Colleges(No.22ZX003)。
文摘The coating material is considered as the key of solid-phase microextraction(SPME)due to the fact that which has much effect on the selectivity and sensitivity of the analytical method.Herein,the porous hollow carbon nanospheres(PHCNs)were synthesized by selectively removing the interior part of solid inhomogeneous nanospheres with acetone.Using PHCNs as new coating material,a SPME fiber was prepared.To the best of our knowledge,PHCNs was utilized as a SPME fiber coating for the first time.The fiber coating material PHCNs demonstrated excellent thermal stability(>800℃)and long usage lifespan(≥60 times).A headspace SPME(HS-SPME)was established to non-contact extract and enrich polycyclic aromatic hydrocarbons(PAHs)prior to gas chromatography-flame ionization detector(GC-FID)analysis.The HS-SPME not only can eliminate non-volatile interferences from matrix,but also be able to protect fiber coating and prolong lifespan of fiber prober.The linearity in the linear range of 0.01-30 ng/m L and limits of detection from 0.003 ng/mL to 0.006 ng/mL were obtained by HS-SPME-GC-FID with PHCNs as fiber coating.The enrichment factors were calculated as 5420-9211 compared with conventional direct introduce analysis.The spiked recoveries of real samples including campus lake water and lime tree honey were obtained from 80.93%to 118.0%with relative standard deviation no higher than 10.6%.The π-π stacking interaction,CH/π interaction,and unique built-in cavities significantly enhance the extraction performance of PHCNs coating fiber to PAHs.This work demonstrated that the PHCNs as fiber coating materials present good application prospects for the extraction and enrichment of trace PAHs from complex matrixes.
文摘采用高密度疏水性低共熔溶剂(Hydrophobic Deep Eutectic Solvents,HDESs)为萃取剂,结合分光光度法,建立了一种涡旋辅助-液相微萃取技术,并成功应用于水中亚甲基蓝的快速测定。HDESs由薄荷醇(氢键受体)和对氯苯酚(氢键供体)按1:1的摩尔比合成,具有优异的疏水性、高密度特性和对亚甲基蓝的较高亲和力。系统考察了萃取剂的种类和用量、涡旋时间及pH值等关键参数对亚甲基蓝萃取效果的影响。在最佳萃取条件(HDESs用量100μL,pH=8,涡旋时间90 s)下,平均加标回收率为89.83%~102.3%,相对标准偏差RSD≤7.58%。该方法在亚甲基蓝的实际水样分析中具有较高的准确性和实用性。
文摘The chlorination process is one of the water treatment method used for the disinfection of water. The disinfection by products are trihalomethanes such as chloroform, dichloromethane, dibromochloromethane and bromoform. A headspace solid-phase microextraction method has been developed for determination oftrihalomethanes in water samples. The experimental parameters such as the stirring rate, extraction time, extraction temperature and desorption time were investigated. The linearity, detection limits and percentage recovery were evaluated. The optimum conditions were stirring rate 800 rpm/min, extraction time 6 min, extraction temperature 20 ~C, desorption time 2.5 min and desorption temperature 220 ~C. The detection limits were 0.01 ~g/L and the recoveries were in the range of 86-110 %, The proposed method was successfully applied to determination of THM4 in tap water samples. The THM4 contents were varied depending on the sample sites and the season. The total THM4 contents in cool, summer and rainy season were in the range of 27.58-41.89, 32.06-60.73 and 46.26-69.87 p.g/L, respectively. Confirmation of the detected compounds in water samples were performed by gas chromatograph-mass spectrometer. The mass spectra of the target compounds in water samples is in good agreement with trihalomethanes standard spectra.
文摘该研究通过顶空固相微萃取-气相色谱-质谱联用技术(headspace-solid phase microextraction-gas chromatography-mass spectrometry,HS-SPME-GC-MS)和高通量测序技术系统解析了3种大曲的特征香气化合物及微生物群落结构。研究发现,3种大曲分为以吡嗪类或以酯类化合物为主体风味两类。采用多元统计分析并根据变量投影重要性指标(variable importance in the projection,VIP)分析共鉴定出31种特征香气化合物。利用高通量测序技术对大曲的细菌群落结构进行解析,结合相关性分析,从多个维度判定了其核心微生物为火山渣芽孢杆菌属(Scopulibacillus)和芽孢杆菌属(Bacillus),其与多种吡嗪类、酚类、醇类等特征风味物质显著相关。通过分离培养及固态发酵实验探究其风味代谢能力,核心微生物的应用结果表明大曲细菌菌群的生物量及吡嗪类化合物的含量明显提升,改变了大曲的香气组成,进一步证实了其对大曲主体风味的调控功能。该研究在实现大曲风味定向调控、提升白酒品质方面具有重要意义。
