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1.
顶空衍生化固相微萃取法测定酱油中3-氯-1,2丙二醇   总被引:1,自引:0,他引:1  
建立顶空衍生化固相微萃取测定酱油中3-氯-1,2丙二醇(3-MCPD)的方法。聚乙二醇-二乙烯基苯(CW-DVB)萃取纤维先顶空吸附苯基硼酸,然后同时萃取和衍生化样品顶空气体中的3-MCPD和内标物d5-3-MCPD,衍生化产物在进样口热解吸,GC-MS检测,内标法定量,特征离子为m/z196、201。结果表明,样品中3-MCPD质量浓度为0.01~1mg/kg时,工作曲线的线性良好(r=0.9994),添加回收率为89%~104%,检出限为0.01mg/kg。  相似文献   

2.
建立了气相色谱-三重四极杆串联质谱(GC-MS/MS)同时测定调味品中氨基甲酸乙酯(EC)和氯丙醇(3-氯-1,2-丙二醇(3-MCPD)和2-氯-1,3-丙二醇(2-MCPD))的方法。样品添加同位素内标后,采用Extrelut TM NT有机硅藻土填料进行基质固相分散萃取,先用正己烷淋洗除杂,再用乙酸乙酯-乙醚(20∶80,v/v)混合溶剂洗脱被测物,洗脱液经浓缩后采用GC-MS/MS多反应监测(MRM)模式测定。EC、3-MCPD和2-MCPD的方法检出限依次为2、5和5μg/kg,线性范围依次为5~1 000μg/kg(r=0.999 7)、10~1 000μg/kg(r=0.999 1)和10~1 000μg/kg(r=0.999 5)。酱油、料酒(黄酒)、沙拉酱和方便面调味料4种基体中在20、100和400μg/kg 3个水平加标测定的平均回收率和相对标准偏差(RSD,n=7)范围分别为EC:87.7%~104%(RSD为4.3%~10.7%)、3-MCPD:90.1%~109%(RSD为2.6%~10.2%)、2-MCPD:90.9%~103%(RSD为3.0%~9.5%)。在部分酱油、料酒和方便面调味料中同时检测到了EC、3-MCPD和2-MCPD,在部分沙拉酱中检测到了EC或3-MCPD。该法准确、快速,适用于调味品中EC、3-MCPD和2-MCPD的同时检测。  相似文献   

3.
采用同位素稀释气相色谱-质谱联用(GC-MS)法,快速测定酱油中3-氯-1,2-丙二醇(3-MCPD)的含量。试样中加入3-氯-1,2-丙二醇的氘代同位素作为内标,经超声混匀后加入到自行填装的弗罗里硅土柱中,以乙醚洗脱,洗脱液经氮气吹干后在正己烷溶剂中进行衍生化,衍生化试剂采用七氟丁酰咪唑。GC-MS采用选择离子监测(SIM)模式进行定性定量分析。结果表明,本方法的添加回收率为95.0%-101.0%;相对标准偏差为3.2%~4.8%;检出限达到0.010mg/kg。本方法步骤简单,溶剂用量少,定性定量准确可靠。可快速测定酱油等调味品中3-氯-1,2-丙二醇的含量。  相似文献   

4.
酱油中3-氯-1,2-丙二醇(3-MCPD)的暴露评估   总被引:1,自引:0,他引:1  
罗祎  李立  国伟  凌云  储晓刚 《大学化学》2009,24(1):42-44
通过对世界各国和国际组织对3-氯-1,2-丙二醇(3-MCPD)的评估结果分析和研究,结合我国酱油调查消费数据以及生产和检测3-MCPD的含量数据,采用国际食品添加剂联席会议(JECFA)和食品科学委员会(SCF)均推荐的毒性值进行暴露评估,评估结果为:将我国酱油中3-MCPD最高允许量设置为0.4mg/kg,对于人类健康及满足国际贸易的要求是适宜的。  相似文献   

5.
李珊  易青  苗虹  吴永宁 《分析化学》2016,(6):893-900
建立了食用植物油中总氯丙醇脂肪酸酯(氯丙醇酯)的同位素稀释-气相色谱-质谱(GC-MS)检测方法。样品经甲醇钠-甲醇溶液水解,硅藻土小柱净化,七氟丁酰咪唑(HFBI)衍生后,GC-MS 检测,同位素内标法定量。3-MCPD 酯、2-MCPD 酯、1,3-DCP 酯和2,3-DCP 酯在0.050~2.000 mg/ L 浓度范围内,均呈良好线性相关,相关系数(R)均大于0.9995。3-MCPD 酯、2-MCPD 酯、1,3-DCP 酯和2,3-DCP 酯的检出限分别为0.015,0.015,0.030和0.030 mg/ kg,定量限分别为0.050,0.050,0.100和0.100 mg/ kg。以空白特级初榨橄榄油为空白基质的加标回收实验的平均回收率为87.0%~110.5%,相对标准偏差(RSD)均小于10.1%。在74份食用植物油样品中,3-MCPD 酯、2-MCPD 酯和1,3-DCP 酯的检出率分别为94.6%,63.5%和5.4%,未检出2,3-DCP 酯;3-MCPD 酯、2-MCPD 酯和1,3-DCP 酯的含量分别在未检出(ND)~10.646 mg/ kg、ND ~3.617 mg/ kg 和ND ~0.089 mg/ kg 之间。本方法简便、准确、可靠,适用于食用植物油中总氯丙醇酯的测定。  相似文献   

6.
邢晓平  曹玉华 《色谱》2006,24(2):192-195
运用毛细管电泳-电化学检测法研究了水解植物蛋白液中3-氯-1,2-丙二醇(3-MCPD)含量的测定。探索了3-MCPD检测的最佳电泳条件。以328 μm的铜圆盘电极为工作电极,在电极电位为+0.65 V(参比电极为饱和甘汞电极),检测池缓冲液为0.05 mol/L氢氧化钠,运行缓冲液为30 mmol/L硼砂(pH 9.24)时,3-MCPD能被很好地分离。3-MCPD的线性范围为6.6~200 mg/L,检测限为0.22 mg/L。研究了水解缓冲液的pH值、水解温度、水解时间等因素对3-MCPD水解反应的影响,用毛细管电泳-电化学检测法检测水解反应过程中3-MCPD的含量。结果表明,在pH 8.0的水解缓冲液中,将水解植物蛋白调味液前体于90 ℃条件下恒温加热1 h,能有效地控制3-MCPD的含量在1.0 mg/kg以下,从而达到我国食品安全允许的限量标准。  相似文献   

7.
陈捷  王志元 《色谱》2006,24(5):447-450
建立了酸水解植物蛋白及酱油中3-氯-1,2-丙二醇(3-MCPD)的固相萃取-气相色谱/质谱测定方法。样品经Aoisa-HBL固相萃取柱萃取,正己烷-乙酸乙酯净化提取,七氟丁酰咪唑衍生,衍生物经气相色谱/负化学电离-质谱(GC/NCI-MS)选择离子模式(SIM)检测,外标法定量。3-MCPD的定量检测限为0.5 μg/kg,平均回收率为92.2%~97.4%,相对标准偏差为3.6%~10.9%。该方法检测灵敏度高,定性定量准确。  相似文献   

8.
易青  苗虹  吴永宁 《分析化学》2016,(5):678-684
建立了食品中氯丙醇类化合物的非衍生化在线凝胶渗透色谱-气相色谱-串联质谱(Online GPC-GCMS/MS)测定方法,目标化合物包括3-氯-1,2-丙二醇(3-MCPD)、2-氯-1,3-丙二醇(2-MCPD)、1,3-二氯-2-丙醇(1,3-DCP)和2,3-二氯-1-丙醇(2,3-DCP).样品中加入氘代同位素内标后,采用ExtrelutTM NT硅藻土进行固相支持液液萃取净化,用正己烷淋洗去除非极性杂质,以乙酸乙酯萃取目标物,萃取液经浓缩后直接采用Online GPC-GC-MS/MS测定.4种氯丙醇在0.005~1.000 mg/L范围内呈良好线性,相关系数均大于0.999,4种氯丙醇的检出限在0.002~ 0.005 mg/kg之间,定量限在0.005~0.01 mg/kg之间.以空白酱油样品为代表性基质的3个水平(0.02,0.1和0.5 mg/kg)的加标回收率和相对标准偏差(RSD,n=6)分别为94.8%~106.3% (2.2% ~ 10.3%),91.8%~108.8%(2.1%~10.6%)和83.1% ~109.4%(1.3%~9.4%).采用本方法分别对酱油、水解植物蛋白液(粉)、料酒、鸡精、面包和糕点样品进行检测,均得到了满意的测定结果.  相似文献   

9.
采用同位素稀释气相色谱-质谱联用(GC-MS)法,快速测定酱油中3-氯-1,2-丙二醇(3-MCPD)的含量。试样中加入3-氯-1,2-丙二醇的氘代同位素作为内标,经超声混匀后加入到自行填装的弗罗里硅土柱中,以乙醚洗脱,洗脱液经氮气吹干后在正己烷溶剂中进行衍生化,衍生化试剂采用七氟丁酰咪唑。GC-MS采用选择离子监测(SIM)模式进行定性定量分析。结果表明,本方法的添加回收率为95.0%~101.0%;相对标准偏差为3.2%~4.8%;检出限达到0.010mg/kg。本方法步骤简单,溶剂用量少,定性定量准确可靠。可快速测定酱油等调味品中3-氯-1,2-丙二醇的含量。  相似文献   

10.
采用同位素稀释的气相色谱-质谱(GC-MS)联用技术,建立了面包中3-氯-1,2-丙二醇脂肪酸酯(3-MCPD酯)的检测方法.样品经正己烷超声提取后用甲醇钠/甲醇水解,硅藻土小柱净化,提取液经七氟丁酰咪唑(HFBI)衍生后注入GC-MS测定.目标化合物经弱极性的气相毛细管色谱柱分离,采用选择离子监测模式(SIM)监测,以同位素内标进行定量.3-MCPD酯在0.025~1.600 mg/L范围内均呈良好的线性关系,相关系数(r)为0.9999,其在面包中的检出限(LOD)低至10μg/kg.以空白面包样品进行加标水平为40、100、160和240μg/kg的加标回收实验,回收率在78.9%~117.0%之间,相对标准偏差(RSD)为2.1%~4.9%,说明该方法的精密度和准确度均良好.本方法灵敏度高、定性准确,适合于面包中3-MCPD酯的检测.  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.
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   

14.
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   

15.
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   

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.
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   

19.
20.
A general synthesis of previously unknown semicarbazone-based α-amidoalkylating reagents, 4-(tosylmethyl)semicarbazones, has been developed. The synthesis involved three-component condensation of semicarbazones of aliphatic or aromatic aldehydes with the same or other aldehydes and p-toluenesulfinic acid. The scope and limitations of this reaction were investigated. The compounds obtained were demonstrated to be an efficient α-(4-semicarbazono)alkylating agents. They were reacted with H- (sodium borohydride), O- (sodium methylate), S- (sodium phenylthiolate), N- (pyrrolidine, sodium succinimide), P- (trialkyl phosphites), and C-nucleophiles (sodium diethyl malonate) to give the corresponding products of the tosyl group substitution, 4-substituted semicarbazones, including analogues of nitrofurazone. Among the prepared compounds tested in vitro for antibacterial and antifungal activity, three nitrofuryl-containing semicarbazones exhibited high biological activities with minimum inhibitory concentration (MIC) values of 8–32 μg/mL.  相似文献   

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