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1.
运用高效液相色谱-大气压电离串联四极杆质谱(HPLC-APCI(+)MS/MS)内标法分析动物源性食品中多种硝基咪唑类(nitroimidazoles)药物——甲硝唑(MNZ)、地美硝唑(DMZ)、替硝唑(TNZ)、洛硝唑(RNZ)的含量。样品添加氘代标示物HMMNI—D^3、IPZ—OH—D^3后,用乙腈提取,通过OASIS HLB C18 SPE柱净化,Waters Sunfire C18色谱柱分离,采用梯度洗脱,流动相为0.1%甲酸水溶液和0.1%甲酸乙腈溶液;大气压电离源正离子MRM模式检测:MNZ m/z 172.0/82.1,172.0/128.0;DMZ m/z 142.0/81.1,142.0/96.1;TNZ m/z 248.0/121.0,248.0/93.1;RNZ m/z 201.0/140.0,201.0/110.0;IPZ—OH—D^3m/z189.0/125.0,189.0/171.0;HMMNI—D^3m/z161.0/58.0,161.0/143.1。方法定量下限(LOQ,S/N〉10)0.2μg/kg,在质量浓度0.2—25.0μg/L范围内,峰面积与质量浓度成良好线性(r〉0.9991)。  相似文献   

2.
对虾中氯霉素残留的分析方法研究   总被引:16,自引:0,他引:16  
用液相色谱-质谱法定量检测对虾中微量的氯霉素残留。采用乙酸乙酯超声提取对虾组织中的氯霉素残留,以甲醇为流动相,选择m/x321/152为氯霉素的检测离子对,用多反应监测(MRM)技术测定。氯霉素流出液相色谱的时间在1.5min以内;线性范围是0.28-28.0μg/L;线性相关系数为0.99991。对虾中氯霉素的定量检测下限是0.07μg/kg,平均回收率在89%以上。该方法快速、灵敏,定量范围宽,检验结果准确可靠,应用性强。  相似文献   

3.
高效液相色谱法检测鳗鱼中氟苯尼考残留量   总被引:14,自引:0,他引:14  
建立了鳗鱼肌肉中氟苯尼考残留的分析方法。采用乙酸乙酯作为提取剂,提取液挥干后溶于缓冲液中,经正已烷脱脂、C18SPE小柱净化后,采用高效液相色谱进行分析,方法在1~200ng之间呈线性相关;相关系数r=0.9999。对于0.05、0.10、0.50mg/kg 3个添加水平,平均回收率均在90%以上,相对标准偏差为4.24%~7.36%,方法检出限和定量限分别为9.1μg/kg和22.3μg/kg。  相似文献   

4.
建立了鸡肉组织中氯霉素残留的液相色谱-电喷雾质谱联用(LC—ESI—MS—MS)测定法。采用微量化前处理方法,省去固相萃取步骤,以m/z321.0为母离子,m/z152.1、257.0和194.1为子离子,采用多反应监测(MRM)负离子模式对鸡肉组织中的氯霉素残留进行检测、方法的检出限为0.010μg/kg(S/N≥3),定量下限为0.10μg/kg,线性范围为0.100~1.00μg/L,加标回收率为74.3%~84.0%,相对标准偏差(n=6)为7.9%~12.7%。该法具有操作简便、有机试剂消耗量少、测定周期短等优点。  相似文献   

5.
采用高效液相色谱法测定哺乳妇女单剂量静滴甲硝唑 ( 2 0mg/kg ,n =8)、替硝唑 ( 1 3mg/kg ,n =7)乳汁药物浓度 ,色谱柱为 pecoshereC1 8( 3μm ,3.3cm× 4.6mm) ,氯仿提取乳汁中药物 ,其平均回收率大于 88.8% .乳汁中甲硝唑与替硝唑药代动力学参数tmax,Cmax,t1 / 2Ke分别为 1 .7± 1 .0h ,2 0 .1 0± 4.95μg/mL ,6.4± 3.3h和 1 .3±0 .6h ,1 7.2 3± 3.1 2 μg/mL ,1 1 .0± 3.5h .  相似文献   

6.
建立了超高效液相色谱-串联质谱联用法测定奶粉中甲硝唑(MNZ)、二甲硝唑(DMZ)和洛硝哒唑(RNZ)3种硝基咪唑类残留物的方法。样品以乙酸乙酯和乙腈提取,正己烷脱脂,浓缩过滤后进行超高效液相色谱-串联质谱分析,多反应监测正离子模式扫描。实验优化了质谱条件,并考察了方法的灵敏度、准确度、精密度和回收率。甲硝唑、二甲硝唑和洛硝哒唑的线性范围为2.5~100.0μg/L,定量下限均为2.5μg/kg,在2.5、5.0、10.0μg/kg 3个水平的加标回收率为89%~112%,相对标准偏差为4.0%~7.1%。该方法简捷、灵敏度高,可用于奶粉中硝基咪唑残留的检测。  相似文献   

7.
建立了分析海藻类产品中2种无机砷价态的高效液相色谱-原子荧光光谱(HPLC—AFS)联用的分析方法.样品经稀硝酸热浸提后离心,取上清液过C18小柱及0.22μm滤膜,进样分析.结果表明:2种无机砷在5.0~100.0μg/L范围内呈良好的线性关系,相关系数r均大于0.999,As(Ⅲ)的最低定量限为0.01mg/kg,As(V)的最低定量限为0.02mg/kg,As(Ⅲ)和As(V)的样品加标回收率为86.2%~106.5%,相对标准偏差(RSD)为3.47%-6.14%.方法可满足海藻类产品中2种价态无机砷的含量分析要求.  相似文献   

8.
采用反相高效液相色谱/四级杆串联质谱(RP-HPLC/MS/MS)同时测定鸡肉中的5种喹诺酮药物(quinolones,QNs)。均质后的鸡肉样品采用磷酸盐缓冲溶液和乙腈的混和溶液提取。提取液经正己烷液-液分配(LLP)去除脂肪后,用C18固相萃取(SPE)柱净化,氨化甲醇洗脱,洗脱液用氮气吹干,流动相定容后,分析物采用LC/MS/MS电喷雾电离(ESI),正离子,多反应监测(MRM)模式检测,外标法定量。在添加浓度2.5~10μg/kg范围内,5种QNs的回收率在79.8%~95.1%之间;相对标准偏差(RSD)均小于11.7%。环丙沙星、丹诺沙星、恩诺沙星检出限(LOD)为0.5μg/kg,沙托沙星为1.0μg/kg,氟甲喹为0.1μg/kg。  相似文献   

9.
高效液相色谱串联质谱测定蜂蜜、蜂王浆中氯霉素残留   总被引:7,自引:0,他引:7  
前处理方法包括添加同位素内标氯霉素-d5和采用10%偏磷酸沉淀蜂王浆产品中的蛋白质,上清液经乙酸乙酯提取,自制硅胶柱和Oasis小柱净化。净化后的提取溶液用高效液相色谱-电喷雾电离质谱检测,多反应监测3对离子(321.0/256.9、321.0/194.0、321.0/175.8)。该方法对不同基质样品的加标回收率为91%-107%;相对标准偏差小于10%;蜂蜜和蜂王浆的方法检出限分别为0.1μg/kg和0.2μg/kg。  相似文献   

10.
建立了液相色谱-串联质谱(LC—MS/MS)同时检测动物源性食品中14种苯二氮革类药物及其代谢物残留量的测定方法。在pH5.2乙酸铵缓冲溶液中药物残留经酶解后,用氨水调节pH值大于9.5。溶液经乙酸乙酯-异丙醇(体积比5:1)提取和阳离子交换柱(MCX)净化,并用多反应监测技术所确定的定性离子对检测物进行定性和同位素内标法定量。方法的定量下限为1.0μg/kg,线性范围为1.0~20.0μg/L,各基质的加标平均回收率为64%~117%,相对标准偏差为3.6%~12.3%。  相似文献   

11.
In the context of the preparation of camptothecin and luotonin A analogs, the synthesis of some key keto-precursors and their use in Friedländer condensation are described. This paper also focuses on the stability of these keto intermediates and emphasizes the major differences between indolizinones and pyrroloquinazolinones series. Noteworthy is also the report of some original structures isolated as by-products of some experiments.  相似文献   

12.
KMnO4-mediated oxidative CN bond cleavage of tertiary amines producing secondary amine was introduced, which was trapped by electrophiles (acyl chloride and sulfonyl chloride) to form amides and sulfonamides. The reaction could take place at mild condition, tolerating a wide range of function groups and affording products in moderate to excellent yields.  相似文献   

13.
The review contains a concise historical account and information on the most significant researches undertaken by the staff at the A. E. Favorsky Irkutsk Institute of Chemistry, Siberian Branch of the Russian Academy of Sciences on the Chemistry of Heterocyclic Compounds. Dedicated to Academician of the Russian Academy of Sciences B. A. Trofimov on his 70th jubilee. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1443–1502, October, 2008.  相似文献   

14.
Different approaches for the synthesis of 1-benzyloxypyrazin-2(1H)-one derivatives from simple amino acids have been investigated. A library of 33 precursors for the preparation of N-hydroxy pyrazinones was obtained in moderate to good yields.  相似文献   

15.
The highly regioselective Buchwald–Hartwig amination at C-2 of the cheap and readily accessible reagent, 2,4-dichloropyridine with a range of anilines and heterocyclic amines is described. This new methodology is robust and provides a facile access to 4-chloro-N-phenylpyridin-2-amines on 0.25 mol scale. These intermediates undergo a further Buchwald–Hartwig amination at higher temperature to enable rapid exploration of the chemical space at C-4 and to provide a library of 2,4-bisaminopyridines.  相似文献   

16.
A new and simple synthesis of novel N-protected methyl 5-substituted-4-hydroxypyrrole-3-carboxylates, which exist in equilibrium with their 4-oxo tautomers, has been developed in two steps starting from N-protected α-amino acids. The key intermediates are enaminones, which can also be isolated, characterized, and used for the construction of other functionalized heterocycles, before they spontaneously decompose to pyrrole products. 4-Hydroxypyrroles are prone to partial aerial oxidation but can be efficiently alkylated or reduced to stable polysubstituted pyrrolidine derivatives.  相似文献   

17.
The chemoselectivity in the intramolecular CH insertion of various diazosulfonamides has been experimentally studied. The results reveal that the aliphatic 1,4-, 1,5-, or 1,6-C(sp3)?H insertions of diazosulfonamides are not accessible, while the aromatic 1,5-C(sp2)?H insertion can be realized specifically by adjusting the diazo-adjacent group. In addition, the general chemoselectivities in the intramolecular CH insertions of diazosulfonyl compounds are summarized. Generally, diazosulfones undergo both aromatic 1,5-C(sp2)?H and aliphatic 1,5- and 1,6-C(sp3)?H insertions, while diazosulfonates undergo aliphatic 1,5- and 1,6-C(sp3)?H insertions. However, diazosulfonamides only undergo aromatic 1,5-C(sp2)?H insertion.  相似文献   

18.
An efficient approach to the synthesis of highly congested di, penta and hexacyclic pyrazoles as well as imidazole fragment containing novel heterocyclic molecule has been developed through a carbanion induced transformation of suitably functionalized 2H-pyran-2-ones, benzo[h]chromene and thiochromeno[4,3-b]pyrans. Due to the presence of fluorescence, we report their prime application metal sensor as off/on switching in ferric ions.  相似文献   

19.
20.
Quercetin, the polyphenolic compound, which has the highest daily intake, is well known for its protective effects against aging diseases and has received a lot of attention for this reason. Both quercetin 3-O-β-d-glucuronide and quercetin 3′-O-β-d-glucuronide are human metabolites, which, together with their regioisomers, are required for biological as well as physical chemistry studies. We present here a novel synthetic route based on the sequential and selective protections of the hydroxyl functions of quercetin allowing selective glycosylation, followed by TEMPO-mediated oxidation to the glucuronide. This methodology enabled us to synthesize the five O-β-d-glucosides and four O-β-d-glucuronides of quercetin, including the major human metabolite, quercetin 3-O-β-d-glucuronide.  相似文献   

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