固相萃取/高效液相色谱-串联质谱法测定水产品中氨苯砜及其代谢物残留量

建立了高效液相色谱－串联三重四极杆质谱（HPLC－MS/MS）测定水产品中氨苯砜及其代谢物残留量的方法。样品加入D8－氨苯砜内标,经1%氨化乙腈提取,正己烷去脂后,采用MCX阳离子固相萃取柱进行富集和净化,氮吹浓缩至0.2 mL左右。用甲醇和水作为流动相,以CAPCELL PAK C18色谱柱（2.0 mm × 100 mm,3 μm）进行分离,在质谱多反应监测（MRM）、正离子电离模式下测定,采用内标法定量。氨苯砜和N-乙酰氨苯砜在0.1 ~ 5.0 μg/kg范围内线性关系良好,相关系数（r2）均大于0.99,方法检出限（LOD）为0.1 μg/kg,定量下限（LOQ）为0.2 μg/kg。以不同类型的水产品为空白基质,在0.2、1.0、2.0 μg/kg加标水平下,平均加标回收率为94.0% ~ 109%,相对标准偏差（RSD）为2.7% ~ 11%。用该法对药代实验中获得的阳性肌肉样品进行测定,通过对化合物的保留时间和离子对信息进行鉴别,鉴定出氨苯砜的代谢产物为N-乙酰氨苯砜。该方法的检出限低、精密度好、准确度高,能够实现对不同水产品中氨苯砜残留量的准确定性与定量检测。     

动物组织中氨苯砜及其代谢产物残留量的液相色谱串联质谱法测定

建立了动物组织中氨苯砜及其代谢产物N-乙酰氨苯砜的液相色谱-电喷雾串联质谱检测方法(HPLC-ESI MS/MS).采用YMC-Pack Pro C18(3 μm,100 mm×2.0 mm i.d.)反相色谱柱,以碱性乙腈为提取液,以HLB和MCX固相萃取柱为净化柱,乙腈-水为流动相,梯度洗脱,流速0.3 mL/min,以正离子多反应监测模式测定,同位素内标法定量,进样量15 μL.方法的定量下限为0.5 μg/kg,线性范围为0.5 ～5.0 μg/kg,加标回收率为92% ～103%,相对标准偏差为4.8% ～11.0%.该法具有灵敏、准确等优点,适用于动物组织中氨苯砜及其代谢产物N-乙酰氨苯砜残留的确证检测.     

固相萃取-高效液相色谱/串联质谱法测定水产品中硫酸新霉素残留量

建立了一种分析水产品中硫酸新霉素残留量的固相萃取-高效液相色谱/串联质谱法。样品经三氯乙酸水溶液提取,固相萃取小柱净化。用带加热电喷雾离子源的高效液相色谱/串联质谱以选择反应离子监测(SRM)正离子模式检测,基质标准曲线定量。结果显示,在草鱼、斑点叉尾鮰、鳗鲡、南美白对虾和甲鱼空白肌肉中添加硫酸新霉素水平为25~1 000μg/kg时,其加标回收率为91.04%~114.57%,相对标准偏差为1.91%~9.62%。硫酸新霉素的检测限为10μg/kg,定量限为25μg/kg。方法适用于水产品中硫酸新霉素残留量的测定,也适用于硫酸新霉素在水产动物体内组织分布和消除研究。     

气相色谱法和液相色谱-串联质谱法测定水产品中敌敌畏残留量

建立了水产品中敌敌畏残留量检测的两种不同方法,比较了气相色谱(GC)与液相色谱-串联质谱(LC-MS/MS)检测方法的适用性。GC法检出限为3.0μg/kg,定量限为10.0μg/kg;LC-MS/MS法检出限为0.3μg/kg,定量限为1.0μg/kg。当敌敌畏添加水平在5.0~15.0μg/kg时,GC法方法回收率为75.0%~90.9%,相对标准偏差为2.8%~9.6%;LC-MS/MS法方法回收率为89.7%~98.1%,相对标准偏差为1.0%~5.0%。结果表明,应用GC与LC-M S/M S检测方法均能满足水产品中敌敌畏残留分析要求,但在不考虑实验成本的前提下,LC-MS/MS法更具有优势。     

超声萃取/气相色谱-质谱联用法同时测定皮革及其制品中21种有害有机溶剂的残留量

建立了气相色谱-质谱/选择离子监测方法,对皮革及其制品中21种有害有机溶剂的残留量进行了同时测定。该方法以乙酸乙酯为萃取溶剂,45℃下超声萃取皮革及其制品中残留的有害有机溶剂,萃取液经固相萃取柱净化后进行气相色谱-质谱/选择离子监测法分析,外标法定量。结果表明,在信噪比(S/N)为10的条件下,乙二醇二丁醚(EGDBE)、三乙二醇二甲醚(TEGDME)、二乙二醇单丁醚(DEGBE)和三乙二醇单乙醚(TEGEE)的定量下限均为50μg/kg,N-甲基乙酰胺(MA)和N-甲基甲酰胺(MF)的定量下限均为150μg/kg,甲酰胺的定量下限为300μg/kg,其余14种组分的定量下限均为100μg/kg。在3个不同加标水平下,方法的平均加标回收率为82.1%~94.9%,相对标准偏差(RSD,n=9)为1.6%~4.8%。该方法简单快捷,灵敏度高,可用于皮革及其制品中有害有机溶剂残留量的测定。     

改进QuChERS–气相色谱法测定水产品中硫丹残留量

建立了水产品中硫丹残留量的改进样品快速处理技术(QuChERS)–气相色谱法检测方法。水产品样品以乙腈为提取剂,应用改进的QuChERS方法进行净化,并利用气相色谱法进行检测,以基质匹配标准溶液外标法定量。在2~10μg/kg添加水平范围内,α-硫丹和β-硫丹的平均回收率分别为97.8%~107.7%,98.5%~102.9%;测定结果的相对标准偏差分别为1.77%~10.4%,2.55%~5.84%;方法检出限分别为1.8,2.0μg/kg;定量限分别为5.4,6.0μg/kg。该法满足水产品中硫丹残留量的测定要求。     

液相色谱-串联质谱法测定水产品中亮绿、亚甲基蓝及其代谢物残留量

建立了水产品中亮绿、亚甲基蓝及其代谢物残留量同时测定的液相色谱-串联质谱(LC-MS/MS)方法。样品经乙酸铵缓冲溶液和乙腈提取,二氯甲烷液液萃取,PRS固相萃取柱净化,氮吹浓缩,定容后测定。以2 mmol/L乙酸铵(含0. 1%甲酸)、乙腈和甲醇为流动相,CAPCELL PAK C_(18)色谱柱进行分离,在选择反应监测(SRM)模式下测定,外标法定量。在最佳实验条件下,5种化合物在1. 0～100. 0μg/L范围内线性关系良好(r~2 0. 999),检出限(LOD,S/N≥3)均为1. 0μg/kg,定量下限(LOQ,S/N≥10)均为2. 0μg/kg;在水产品中加标水平为1. 0、5. 0、10. 0μg/kg时,回收率为70. 3%～92. 1%,相对标准偏差(RSD,n=6)为2. 3%～13%。该方法灵敏度高,能有效检测水产品中亮绿、亚甲基蓝及其代谢物的残留量。     

微波辅助萃取/气相色谱-串联质谱法同时测定皮革及其制品中5种限用酰胺类溶剂的残留量

建立了同时测定皮革及其制品中5种限用酰胺类溶剂残留量的气相色谱-串联质谱分析方法。以甲醇为萃取溶剂,微波萃取皮革及其制品中残留的限用酰胺类溶剂,萃取物经固相萃取柱净化后,进行气相色谱-串联质谱分析,外标法定量。在优化条件下,甲酰胺、N-甲基甲酰胺、N,N-二甲基甲酰胺、N-甲基乙酰胺、N,N-二甲基乙酰胺的定量下限(LOQ,S/N=10)分别为20,10,1,20,3μg/kg。在3个不同加标水平下,方法的平均加标回收率为81.4%~86.9%,相对标准偏差(RSD,n=9)为4.5%~8.7%。该方法简便快速,灵敏度高,定量下限远小于REACH法规的限量要求,可完全满足皮革及其制品中限用酰胺类溶剂残留量检测工作的要求。     

双柱固相萃取净化-液相色谱-串联质谱法测定牛奶和奶粉中链霉素和双氢链霉素残留量

建立了双柱固相萃取净化-液相色谱-串联质谱(HPLC-MS/MS)测定牛奶和奶粉中链霉素和双氢链霉素残留量的分析方法。样品用H3PO4溶液提取,三氯乙酸沉淀蛋白,苯磺酸型和羧酸型固相萃取柱净化,经Atlantis C18色谱柱分离,以电喷雾离子源在正离子多反应监测(MRM)模式下进行测定。牛奶中链霉素和双氢链霉素的方法检出限均为4μg/kg,定量限均为10μg/kg,奶粉中链霉素和双氢链霉素的方法检出限均为30μg/kg,定量限均为80μg/kg,方法回收率为80%~86%,相对标准偏差为5.9%~11.5%。本方法适用于牛奶和奶粉中链霉素和双氢链霉素残留量的测定。     

改良的QuEChERS结合高效液相色谱-串联质谱同时测定水产品中7种阿维菌素类药物残留

建立了改良的QuEChERS结合高效液相色谱-串联质谱(HPLC-MS/MS)同时测定水产品中7种阿维菌素类药物(阿维菌素、伊维菌素、多拉菌素、塞拉菌素、乙酰氨基阿维菌素、莫西菌素和埃玛菌素)的分析方法。样品经0.2%(v/v)氨化乙腈提取,3 g无水硫酸镁和2 g无水硫酸钠除水剂和沉淀蛋白质,100 mg十八烷基硅烷(C18)和500 mg无水硫酸镁净化。以0.1%(v/v)甲酸乙腈(含5 mmol/L乙酸铵)-0.1%(v/v)甲酸水溶液(含5 mmol/L乙酸铵)为流动相,采用Varian Pursuit ULTRA C8色谱柱(100 mm×2.0 mm,2.8μm)进行分离。在加热电喷雾离子(HESI)源、正离子模式下采用多反应监测模式检测,基质匹配标准曲线外标法定量。阿维菌素、伊维菌素、多拉菌素、塞拉菌素、乙酰氨基阿维菌素和莫西菌素在2~200μg/L范围内、埃玛菌素在0.2~20μg/L范围内呈线性相关,相关系数(r)均≥0.997 2,水产品中阿维菌素类药物的加标回收率为71.6%~112.8%,相对标准偏差(RSD)为4.7%~13.1%,不同水产品的基质效应均小于15%。阿维菌素、伊维菌素、多拉菌素、塞拉菌素、乙酰氨基阿维菌素和莫西菌素的定量限均为5μg/kg,埃玛菌素的定量限为0.25μg/kg。该法操作简便,重复性好,适用于水产品中7种阿维菌素类药物残留量的同时测定。     

氯离子加速的铜基芬顿反应用于对多巴胺的比色检测EI北大核心CSCD

基于氯离子加速的铜基芬顿反应构建了一种便捷、快速、无标记的比色分析方法并将其应用于多巴胺(DA)的快速检测。Cl^(-)可以加速Cu^(2+)催化过氧化氢(H_(2)O_(2))产生羟基自由基,进而氧化3,3′,5,5′-四甲基联苯胺(TMB)显色,而DA可以与Cu^(2+)配位,使反应速率减慢。基于此,可以利用检测液的颜色及TMB^(2+)在452 nm处吸光度的变化来实现对DA的检测。DA的浓度在0~10μmol/L及10~50μmol/L范围内与TMB^(2+)在452 nm处的吸光度呈线性相关,检出限为0.5μmol/L。本方法已用于实际样品的检测。     

4D-proteomics-based breast cancer progressionEI北大核心CSCD

：The occurrence and development of breast cancer go through multiple processes，and the protein molecular information in its evolution is intricate and complex. The 4D-proteomics technique was used to investigate the tumor progression of MMTV-PyMT transgenic mice. The results of protein identification and differential expression analysis showed that a total of 5819 proteins were identified in 4D-proteomics analysis and 5667 proteins were quantifiable. Compared with 3-week-old tumors，a total of 270 differentially expressed proteins were found in the 5-week-old tumors，while 255 proteins in the 7-week-old tumors. We also detected 23 of proteins （such as，Srpk11 and Tinagl1）with gradual up-regulation and 35 of proteins （such as，Pdgfrb， Col1a2 and Col1a1）with gradual down-regulation during the tumor progression，including 3-，5-and 7-weeks. We also performed bioinformatics analysis，including subcellular localization，GO function analysis and pathway enrichment analysis. The results showed that the biological processes（immune regulation and lipid metabolism） and enrichment pathways （metabolic pathway）involved in differentially expressed proteins remained the same during the tumor progression，but some cellular components and molecular functions changed，such as，protein locations were extracellular region and membrane in 5-weeks-old tumors as well as cytoplasm in 7-weeks-old tumors. And important protein functions were protein binding functions in 5-weeks-old tumors as well as nucleotide binding in 7-weeks-old tumors. The acquired protein biomarkers and pathways could help with the accurate exploration of molecular mechanisms of tumor progression，screening of molecular targets of breast cancer，and evaluation of personalized treatment programs. © 2023, Youke Publishing Co.,Ltd. All rights reserved.     

Effect of metal ions on enantioseparation of five amino acids by ligand exchange capillary zone electrophoresisEI北大核心CSCD

Enantioseparation of five amino acids was conducted by chiral ligand exchange capillary zone electrophoresis (CLE-CZE). L-His and different metal ions in a certain proportion were used to form chiral recognition complexes. The enantiomers were exchanged with L-His ligands in the complex. Then, the separation of enantiomers was obtained according to the different ligand exchange ability. Effects of the valence and the electron layers of metal ions on the resolution were investigated systemically. Baseline separation of D, L-Phe, D, L-Tyr and D, L-Trp was obtained within 12 min when 4 mmol/L Co(Ⅱ) and 8 mmol/L L-His were added to the phosphate buffer solution (20 mmol/L, pH 8.0). The resolutions of D, L-Phe, D, L-Tyr and D, L-Trp were 1.53, 2.04, and 1.58, respectively. Partial chiral separation of D, L-Ser and D, L-Val was achieved under the same conditions. When Co(II) was used as the central ion, the resolution was better than that of Cu(II) and Zn(II), although they had the same number of electron layers and valence. The resolution of amino acids with Ag(I) as the central ion was not as good as that of divalent metal ions. Metal ions with three electron layers had better separation results than that with four electron layers. © 2023, Youke Publishing Co.,Ltd. All rights reserved.     

Cascaded strand displacement for non-enzymatic target recycling amplification electrochemical detection of SARS-CoV-2EI北大核心CSCD

An electrochemical biosensor for low cost and highly sensitive and selective detection of SARS-CoV-2 target nucleic acid was developed based on two cascaded toehold-mediated strand displacement reactions (TSDRs). Driven by thermodynamic entropy, the target nucleic acid bound to the first toehold region of the probes, leading to the first TSDR and the second toehold region exposed. Subsequently, the methylene blue (MB)-modified signal probe triggered the second TSDR and led to cyclic reuse of the target nucleic acid. Based on cascaded TSDRs, a large number of signal probes were combined on the sensor surface to produce significantly enhanced square wave voltammetry (SWV)electrochemical signals. The results showed that the SWV signal intensity was proportional to the logarithm of the target nucleic acid concentration, and had a good linear relationship in the range of 5×10-14-5×10-10 mol/L with a detection limit of 1.8×10-14 mol/L. Moreover, the sensor could be employed to monitor SARS-CoV-2 nucleic acid in 10% serum samples. © 2023, Youke Publishing Co.,Ltd. All rights reserved.     

Pd nanoparticles on boron doped graphene catalyst for electrochemical detection of hydrogen peroxide prepared by electroless deposition methodEI北大核心CSCD

Taking advantage of large conjugated structure and reductivity of boron-doped graphenethe palladium nanoparticles/boron-doped graphene catalyst was prepared by electroless deposition method using boron-doped graphene as reductant and stabilizer. The average size of palladium nanoparticles highly dispersed on the surface of boron-doped graphene was about 6.5 nm. The electrochemical sensor was prepared by modifying the as-formed catalyst on the surface of glassy carbon electrode. The obtained electrochemical sensor exhibited an excellent electrochemical catalytic activity for H2 O2 . It exhibited high sensitivity with the detection limit as low as 830 nmol/L and good linearity in the range of 2.5-300 μµmol/L for detection of H2 O2 . It could be utilized for the determination of H2 O2 in milk samples. © 2022, Youke Publishing Co.,Ltd. All rights reserved.     

超高效液相色谱-三重四极杆质谱法测定化妆品中秋水仙碱、秋水仙胺和秋水仙碱苷EI北大核心CSCD

建立了一种同时测定化妆品中秋水仙碱、秋水仙胺和秋水仙碱苷的超高效液相色谱-三重四极杆质谱分析方法。试样经正己烷饱和的甲醇-乙腈(1∶1,V/V)混合溶剂超声提取,蜡基类样品经正己烷溶解分散后提取,膏霜类样品在提取液中加入乙酸铵以改善样品乳化情况,提取液离心过滤后,以5 mmol/L乙酸铵(含0.1%甲酸)-甲醇作为流动相梯度洗脱,经ACQUITY UPLC BEH C_(18)色谱柱分离后,采用超高效液相色谱-三重四极杆质谱在电喷雾正离子电离模式和多反应监测(MRM)模式检测。3种化合物在0.5~10μg/L范围内线性关系良好,相关系数大于0.995,检出限为3.0μg/kg,定量限为10.0μg/kg,在10.0,20.0,100μg/kg 3个加标水平下的平均回收率为81.5%~109.2%,相对标准偏差为0.5%~8.7%。该方法适用于化妆品中秋水仙碱、秋水仙胺和秋水仙碱苷的测定。     

Determination of 15 polycyclic aromatic hydrocarbons in lotus root by QuEChERS-high performance liquid chromatographyEI北大核心CSCD

A method for the determination of 15 priority polycyclic aromatic hydrocarbonsPAHsin lotus root by QuEChERS technique combined with high performance liquid chromatography HPLC was established. Lotus root samples were extracted by acetonitrilefiltrated after salting out and purified by C18 and primary secondary aminePSAsorbent. Then the 15 kinds of PAHs were analyzed by HPLC with diode array detector or fluorescence detector after being separated by Athena PAHs column. When the 15 kinds of PAHs were analyzed by diode array detectorthe linear relationships were good between 0.02 and 1.0 mg/L with the correlation coefficients above 0.99 for all the 15 kinds of PAHs. The limits of quantitation were 0.02 mg/kg for allthe average recoveries of the 15 kinds of PAHs were 84.7%-117.1%and the relative standard deviations were 0.73%-11%. When the 14 kinds of PAHsexcept for acenaphthyleneanalyzed by fluorescence detectorthe linear relationships were good between 0.001 and 1.0 mg/L with the correlation coefficients above 0.99 for all the 14 kinds of PAHs except for acenaphthylene. The limits of quantitation were 5 μµg/kg for allthe average recoveries of the 14 kinds of PAHsexcept for acenaphthylenewere 69.1%-111.8%and the relative standard deviations were 0.18%-9.7%. Diode array detector and fluorescence detector are complementary. Diode array detector can analyze all the PAHsbut its sensitivity is relatively low. Fluorescence detector is not suitable for acenaphthylene with weak fluorescence signalbut its sensitivity is much higher than that of diode array detector. This method is suitable for simultaneously and quickly determination of 15 kinds of PAHs in lotus root. © 2022, Youke Publishing Co.,Ltd. All rights reserved.     

Determination of cobalt ion based on polyethyleneimine modified silver nanoclustersEI北大核心CSCD

PolyethyleneiminePEImodified silver nanoclustersAg NCswere synthesized through chemical reduction method by using PEI as stabilizerAgNO3 as silve source and ascorbic acid as reducing agentand it was applied to the detection of cobalt ions. It was found that the fluorescence of the silver nanoclusters was quenched by Co2+ for the aggregation of PEI-Ag NCs caused by the coordination between cobalt ion and amino group on polyethyleneimine. Under the optimized experimental conditionsthe fluorescence quenching degree of PEI-Ag NCs was piecewise linear with the concentration of cobalt ion in the range of 8.30×10-7-4.17×10-4 mol/L and the detection limit was 0.41 μµmol/L. © 2022, Youke Publishing Co.,Ltd. All rights reserved.     

新型低共熔溶剂的制备及其在分散液-液微萃取水样中臧红T和胭脂红的应用EI北大核心CSCD

建立了一种基于低共熔溶剂的旋涡辅助分散液-液微萃取和高效液相色谱连用检测水样中臧红T和胭脂红染料的方法。制备了一类分别由苄基三乙基溴化铵、苄基三丁基溴化铵、苄基三乙基氯化铵或苄基三丁基氯化铵(氢键受体)和正辛酸(氢键供体)组成的新型疏水性低共熔溶剂。最佳萃取条件为:选取苄基三丁基氯化铵和正辛酸(摩尔比为1∶2)制备的低共熔溶剂为萃取剂,萃取剂用量为75μL,萃取时间为1 min,溶液pH=7,NaCl浓度为3 mg/mL。在最优化条件下,检测臧红T和胭脂红的线性范围为4.8~1000 ng/mL;相关系数(R^(2))分别为0.9981和0.9987;检出限分别为1.5和1.8 ng/mL;定量限均为4.8 ng/mL。将该方法应用于实际水样中臧红T和胭脂红的测定,加标回收率为88.5%~113.6%,相对标准偏差均低于8.8%。     

Simultaneous determination of 73 fragrance allergens and 4 pesticides in silicone mosquito repellent products by ultrasonic solvent extraction combined with gas chromatography-tandem mass spectrometryEI北大核心CSCD

以73种致敏性芳香剂与4种农药为目标化合物,建立了硅胶驱蚊手环中致敏性芳香剂与农药同时测定的气相色谱-串联质谱(GC-MS/MS)方法。DB-17MS色谱柱分离,动态多反应监测模式(dMRM),外标法定量。采用阳性样品优化前处理条件,结果显示,以无水乙醇为提取溶剂、密闭控温超声提取可以有效提取硅胶样品中农药与致敏性芳香剂。最佳条件下,77种目标分析物在0.1~100 mg/L范围内线性良好(R^(2)>0.9920),定量限0.02~5.0 mg/kg,回收率66%~120%,相对标准偏差0.2%~9.8%。采用上述方法对14个驱蚊手环样品进行检测,共检出31种目标化合物。该方法可用于硅胶样品中致敏性芳香剂和农药高通量定向筛查。