甲氧基苯并噻唑偶氮-8-羟基喹啉-5-磺酸的合成及与钴的显色反应研究

合成了新显色试剂7-[6-甲氧基-(2-苯并噻唑偶氮)]-8-羟基喹啉-5-磺酸.该试剂在弱酸性(pH5.0)条件下,在有非离子表面活性剂存在时,与钴形成紫红色的络合物.其最大吸收波长λ_(max)=560nm,表观摩尔吸光系数为6.17×10~4L·mol~(-1)·cm~(-1).钴含量在0～8μg/10ml范围内服从比耳定律.应用拟定的方法测定了维生素B~(12)等试样中的钴,结果满意.     

1-(6-硝基-2-苯并噻唑)-3-(5-溴-8-喹啉)-三氮烯与Co(Ⅱ)的高灵敏显色反应及其应用

报道了在CPB 存在下,新试剂1-(6-硝基-2-苯并噻唑)-3-(5-溴-8-喹啉)-三氮烯(NBTBQT)与钴的显色反应.在pH 9.5的硼砂-NaOH缓冲介质中,试剂与钴形成2:1 深蓝色络合物,其最大吸收波长位于655 nm处,表观摩尔吸光系数为1.94×105 L·mol-1·cm-1,钴的质量浓度在0～0.24 mg/L 的范围内符合比尔定律.方法应用于维生素B12注射液和水系沉积物的测定.     

1-(4-磺基苯)-3-(6-溴-苯并噻唑)-三氮烯合成及与钴(Ⅱ)的显色反应研究

合成了一种新试剂1-(4-磺基苯)-3-(6-溴-苯并噻唑)-三氮烯(SPBMBTT),并研究了在非离子表面活性剂Tween-80存在下与钴(Ⅱ)的显色反应。在pH 11.3的Na2CO3-HCl缓冲溶液中,试剂与钴(Ⅱ)形成配合比为1∶2的橙红色配合物,用双峰双波长法测定,其表观摩尔吸光系数ε=2.29×105L.mol-1.cm-1,钴(Ⅱ)含量在0~240μg/L范围内符合比耳定律。此法已用于vita-min B12针剂和茶叶中微量钴的测定,结果满意。     

新显色剂8-(2-苯并噻唑偶氮)-5-氨基喹啉的合成及其与钴(Ⅱ)显色反应的研究

合成了3种5-氨基喹啉8位偶氮新试剂, 研究了其与钴(Ⅱ)的显色反应. 对8-BTA-5-AQ与钴的显色反应作了详细研究. 在pH 3.8的缓冲溶液中, 试剂与钴(Ⅱ)形成紫红色配合物, 其最大吸收峰位于620 nm, 表观摩尔吸光系数为5.5×104 L·mol-1·cm-1, 钴量在0～0.40 μg/mL范围内符合比尔定律. 方法已用于合金钢中微量钴的测定.     

meso-四(3-氯-4-磺酸苯基)卟啉与钴(Ⅱ)显色反应的光度法研究

研究了弱碱性介质中新试剂meso-四(3-氯-4磺酸苯基)卟啉(m-ClTPPS4)与钴(Ⅱ)的显色反应条件.不加任何辅助试剂,沸水浴中加热,m-ClTPPS4与Co(Ⅱ)形成检测灵敏度很高的1:1(M:L)配合物,其最大吸收波长为426 nm,表观摩尔吸光系数达4.0×105L@mo1-1@cm-1.钴(Ⅱ)含量在0～5.0μg/25 mL范围内符合比耳定律.该方法应用于维生素B12中钴(Ⅱ)的测定,结果满意.     

5-(5-氟-2-吡啶偶氮)-2,4-二氨基甲苯与钴显色反应的研究及应用

研究了新合成试剂5-(5-氟-2-吡啶偶氮)-2,4-二氨基甲苯(5-F-PADAT)与钴(Ⅱ)的显色反应。实验表明,在pH4.7~9.0范围内,钴与试剂形成紫红色配合物,其最大吸收波长位于506 nm。该配合物在无机酸作用下,可转化为另一具有较高吸收特性的质子化型体,最大吸收波长红移到565 nm,适宜的酸浓度范围分别为:0.24~3.6 mol/L HClO4、0.16~3.84 mol/L H2SO4、0.48~2.4 mol/L HCl、0.64~3.84 mol/L H3PO4。配合物表观摩尔吸光系数ε565=9.1×104L.mol-1.cm-1,钴(Ⅱ)质量浓度在0~0.5μg/mL内符合比尔定律。所拟方法已应用于维生素B12针剂中微量钴的测定。     

新试剂5-(2''-氨基-4''-羟基苯偶氮)邻苯二甲酰肼(AHPP) 的合成及其光度法测定钴

本文报道新试剂5-(2′-氨基-4′-羟基苯偶氮)邻苯二甲酰肼的合成,并研究了该试剂用于光度法测定钴的反应条件.钴与试剂在 pH7.7～9.0(0.06mol·L~(-1)Na_2B_4O_7-HCl缓冲介质)时形成稳定配合物,最大吸收位于542nm处,摩尔吸光率为5.7×10~3L·mol~(-1)·cm~(-1),配合物的组成为 1:2的 Co:AHPP,钴浓度在0～1.02×10~(-4)mol·L~(-1)范围内符合Beer′s law.试验了共存离子的影响,发现除Cu(Ⅱ),Ni(Ⅱ)略有干扰(可掩蔽)外,其它常见离子均允许大量存在,该法已直接用于不锈钢和维生素B_(12)中钴的测定.     

2,5-二(邻羟苯基)-1,3,4-噻二唑与钴显色反应的研究

研究了在两性表面活性剂十二烷基二甲基氧化胺(OB-2)存在下,钴与新合成试剂2,5-二(邻羟苯基)-1,3,4-噻二唑的显色条件及应用,建立了测定钴的新方法。在pH 8.0 NH3-NH4Cl缓冲溶液中,钴与2,5-二(邻羟苯基)-1,3,4-噻二唑反应生成1∶3黄绿色螯合物,最大吸收波长为410 nm。加入OB-2后,使其最大吸收波长红移至470 nm,表观摩尔吸光系数为5.74×104L.mol-1.cm-1,钴质量浓度在0.2~2.4μg/mL范围内服从比耳定律,可用于维生素B12针剂和水样中钴的测定,回收率在97.7%~98.2%之间。     

新显色剂2-(5-羧基-1,3,4-三氮唑偶氮)-5-二乙氨基酚与钴的显色反应的研究

研究了新显色剂2-(5-羧基-1,3,4-三氮唑偶氮)-5-二乙氨基酚与钴的显色反应,试剂与钴在pH 6.0～8.0范围内形成稳定的紫红色络合物,其组成比为1:3,λ_(max)=540nm,络合物表观摩尔吸光系数为5.7×10~4,Co~(2+)在0～0.8mg·L~(-1)范围内符合比耳定律,络合物在强酸溶液中能稳定存在,可消除大量离子的干扰,有良好的选择性,方法可以不经分离直接测定维生素B_(12)和合成工业废水中的微量钴,结果满意。     

用2-(5-硝基-2-吡啶偶氮)-5-二乙氨基苯酚反相高效液相色谱测定痕量铁、钴、镍

本文采用新试剂2-(5-硝基-2-吡啶偶氮)-5-二乙氨基苯酚(5-NO_2-PADAP)为柱前衍生试剂,不需对离子试剂,用含40mmol/L 的 pH6.0的乙酸-乙酸钠缓冲溶液和10~(-4)mol/LEDTANa_2的甲醇-水溶液(67.5:32.5)为流动相,在 ODS 柱上,20min 内 HPLC 测定了 Fe(Ⅲ)、CO(Ⅱ)和 Ni(Ⅱ)的5-NO_2-PADAP 的络合物,这是同类衍生试剂中最简单流动相体系。当信噪比 SNR=2时,检出限分别为0.17、0.17和0.09ng/ml。是同类体系中灵敏度最高的。方法用于同时测定硝酸试剂和茶叶中的铁、钴和镍,结果良好。     

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.     

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。     

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。     

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.     

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.     

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.     

高效液相色谱-紫外检测法测定水产品中氨苯砜及其代谢物残留量EI北大核心CSCD

建立了水产品中氨苯砜及其代谢产物N-乙酰氨苯砜残留量同时测定的高效液相色谱-紫外检测法(HPLC-UV)。样品经1%氨化乙腈提取,正己烷去脂,MCX阳离子固相萃取柱富集净化,氮吹浓缩,定容过膜后测定。以甲醇和水为流动相,ZORBAX SB-C_(18)色谱柱梯度洗脱分离,采用保留时间定性,外标法定量。在最佳检测条件下,目标化合物质量浓度在5~200 ng/mL范围内线性关系良好(R^(2)> 0.999),检出限(LOD)为10.0μg/kg,定量限(LOQ)为20.0μg/kg。以不同类型的水产品为空白基质,在20,50,100μg/kg加标水平下,氨苯砜的回收率为70.1%~81.7%,N-乙酰氨苯砜的回收率为84.2%~109.5%,相对标准偏差(RSD)均小于10%。该方法能够实现大批量水产品中氨苯砜及其代谢物残留量的检测。     

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%。     

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.