气相色谱法测定食品接触材料中12种单体的迁移量

目的建立同时测定食品接触材料中12种丙烯酸酯和甲基丙烯酸酯类单体迁移量的分析方法。方法采用水、乙酸(质量分数为3%)、乙醇(体积分数为10%)和橄榄油浸泡食品接触材料,将得到的水、乙酸、乙醇等水性模拟物和橄榄油模拟物分别经过80,90℃顶空加热20 min后,通过DB-624石英毛细管柱(30 m×0.32 mm×1.8μm)分离,顶空进样分析,氢火焰离子化检测器检测,保留时间定性,峰面积定量。结果 12种单体在0.1~50 mg/L(水性模拟物)及0.5~50 mg/kg(橄榄油模拟物)的浓度范围内呈良好线性,相关系数R大于0.999。加标回收率为89.3%~109.6%,相对标准偏差为1.13%~7.55%。结论该方法前处理简便,分离度好,分析灵敏度高,满足食品接触材料中12种丙烯酸酯和甲基丙烯酸酯类单体迁移量的分析要求。     

PC 制品中双酚 A 定量分析方法的研究

目的研究双酚A在水、乙醇(质量分数为65%,全文同)、乙酸(4%)等3种食品模拟物中的迁移行为,探讨温度对双酚A迁移行为的影响,进而建立检测聚碳酸酯(PC)制品中双酚A向食品模拟物迁移溶出的定量分析方法。方法采用溶剂萃取法提取食品模拟物中的双酚A,并用GC-MS进行迁移量测定。结果该方法的工作曲线在0.05~200 mg/L范围内线性关系良好(r=0.9997),检出限为0.02 mg/L,检测方法灵敏,精确度较高。双酚A在3种模拟液中的检出量大小顺序为乙醇(65%)水乙酸(4%)。结论双酚A在同一食品介质中的迁移量随温度的升高呈上升趋势,且向水和酒精类食品的迁移比向酸性食品的迁移显著。     

液相色谱——双质谱法测定食品接触材料双酚A双酚S的迁移量

选取了食品接触材料制品塑料杯和金属罐为研究对象,建立对双酚A、双酚S迁移量同时检验的液质法。确定了仪器条件,在本条件下,双酚A、双酚S检出限为0.002mg/L,定量限为0.006 mg/L。加标水平在0.5～1.0mg/L时,双酚A回收率为94.0%～97.9%,RSD值(n=6)为2.5%～2.9%;双酚S回收率为94.4%～95.3%,RSD值(n=6)为1.8%～2.5%。比较了三氯甲烷与二氯甲烷模拟液对塑料杯中双酚A、双酚S迁移试验,结果显示二氯甲烷模拟液迁移能力更强。比较了三氯甲烷、正庚烷、4%(v/v)乙酸溶液、4%(m/v)碳酸钠溶液四种模拟液对金属罐（马口铁材质）中双酚A、双酚S的迁移试验,结果显示三氯甲烷及正庚烷对双酚A、双酚S迁移能力较强。该方法检出限低,准确、高效、稳定,可用于食品接触材料制品中双酚A、双酚S同时检验。     

食品模拟物中 2,2,4,4-四甲基-1,3-环丁二醇迁移量的测定

目的建立气相色谱/质谱法测定食品模拟物中2,2,4,4-四甲基-1,3-环丁二醇(TMCD)迁移量的方法。方法食品模拟物经甲醇提取后,采用DB-5ms色谱柱程序升温分离,以72作为目标离子,用外标法进行定量。结果水基模拟物中的TMCD在0.25~25.0 mg/L范围内线性良好,定量限为0.25 mg/L;脂类食品模拟物(橄榄油)中的TMCD在1.25~25.0 mg/L范围内线性良好,定量限为1.25 mg/L;相关系数均不小于0.995,回收率为82.2%~106.9%,相对标准偏差(n=6)为0.3%~8.1%。结论该方法快速、准确、灵敏,适用于食品模拟物中2,2,4,4-四甲基-1,3-环丁二醇(TMCD)迁移量的测定。     

高效液相色谱法同时测定食品接触材料中九种抗氧剂的特定总迁移量

建立了高效液相色谱(HPLC)法检测五种食品模拟物(10%乙醇、3%乙酸、20%乙醇、50%乙醇和异辛烷)中没食子酸丙酯(Nipa 49)、没食子酸辛酯(Stabilizer GA-8)、没食子酸十二酯(Progallinla)、2,4-二(十二烷基硫甲基)-6-甲基苯酚(RC 1726)、4,6-二(辛硫甲基)邻甲酚(AO 1520)、2,2'-亚甲基二[4-甲基-6-(1-甲基环己基)]苯酚(Ionox wsp)、2,2'-甲亚基双(6-环己基-4-甲基酚)(ZKF)、2,2'-亚甲基双-(1,1-二甲基乙基)-4-乙基苯酚(AO 425)和2,2'-亚甲基双-(4-甲基-6-叔丁基苯酚)(AO 2246)九种抗氧剂的特定总迁移量[SML(T)]。食品模拟物浸泡待测样品,冷却至室温并混匀,水基食品模拟物(10%乙醇、3%乙酸、20%乙醇、50%乙醇)用含0.05%三(2-羧乙基)膦盐酸盐(TCEP)的四氢呋喃1:1稀释,经亲水性聚四氟乙烯针头过滤器过滤后进样;异辛烷食品模拟物旋蒸氮吹浓缩至近干,用含0.05%TCEP的甲醇定容,再经亲水性聚四氟乙烯针头过滤器过滤后进样。用C8柱梯度洗脱分离;检测波长为285 nm;进样量为20μL;方法在五种食品模拟物中的定量限为0.005~1.0 mg/L;水基食品模拟物在3~72、0.5~12、0.3~7.2或0.15~3.6 mg/L,异辛烷食品模拟物在30~720、5~120、3~72或1.5~36 mg/L范围内线性关系良好(r20.9982);0.3~84 mg/L三水平的加标回收率为83.7%~113%,相对标准偏差为0.8%~11.2%。结果表明,该方法色谱分离和线性关系较好,回收率和准确度较高,定量限完全满足欧盟(EU)NO 10/2011法规附表2中九种抗氧剂SML(T)的限量要求,并已应用于实际样品的检测。     

HPLC测定聚丙烯餐具中12种抗氧化剂迁移量

目的建立高效液相色谱法,测定聚丙烯餐具中12种抗氧化剂的迁移量。方法采用蒸馏水、质量分数为3%的乙酸溶液、质量分数为10%的乙醇溶液、质量分数为20%的乙醇溶液、质量分数为50%的乙醇溶液、异辛烷、聚2,6-二苯基苯乙烷这7种食品模拟物浸提聚丙烯餐具中的12种抗氧化剂,经高效液相色谱-二极管阵列检测器测定,利用外标法进行定量。结果质量浓度为5.0~100.0 mg/L的范围内,12种抗氧化剂线性关系良好,R2≥0.9995,检出限为0.5~2.0 mg/L,平均回收率在87.1%~98.7%,相对标准偏差在0.8%~3.1%。结论利用HPLC法测定聚丙烯餐具中12种抗氧化剂的迁移量,该方法操作简便、快速、灵敏,可为食品接触材料中抗氧化剂分析提供参考。     

气相色谱法测定塑料奶瓶中迁移出的双酚A

本文介绍了塑料奶瓶(以聚碳酸酯为主要材质)中迁移出双酚A的气相色谱检测法。样品用食品模拟物(水)浸泡后,浸泡液经固相萃取(SPE)富积,五氟丙酸酐(PFPA)衍生后用GC-ECD检测。该方法的最低检测检出限为0.2μg/L,在0.2μg/L～50μg/L的线性范围内,相关系数r=0.9994。三种不同添加水平,三次平行实验平均回收率为92.3%～98.5%。方法的精密度(RSD)为3.35%～5.96%。该方法灵敏度高,准确,可靠,适用于聚碳酸酯奶瓶中迁移出微量双酚A的检测。     

塑料瓶中对苯二甲酸特定迁移量的研究

目的研究了高效液相色谱法测定不同食品模拟物中对苯二甲酸迁移量的适用性。结果以水、10%(v/v)乙醇、50%(v/v)乙醇、4%(v/v)乙酸作为食品模拟物,在0.8～16.0μg/m L范围内,对苯二甲酸在4种食品模拟物中的响应线性关系良好(r2≥0.999),加标回收率在98%～103%内。结果表明,该方法的色谱分离和线性关系较好,回收率高,完全满足国家标准中对苯二甲酸的的限量要求。     

气相色谱-质谱法测定食品接触耐高温材料中氯苯和对二氯苯迁移量

目的利用气相色谱-质谱联用法测定食品接触耐高温材料中氯苯类物质(氯苯、对二氯苯等)的迁移量。方法从水基、酸性、醇类、油基等食品模拟物的迁移试验中得到的样品,通过正己烷或甲醇等有机溶剂萃取后,提取液中的氯苯类物质经由键合聚乙二醇的毛细管柱分离,最终在质谱中进行检测分析。结果在优化萃取溶剂、色谱柱等检测条件下,该方法可有效测定食品模拟物中氯苯、对二氯苯等物质的迁移量,在0.05~50 mg/kg(水性模拟物)或0.2~50 mg/kg(油性模拟物)的范围内线性良好,检出限可达到0.02 mg/kg(水性模拟物)或0.1 mg/kg(油性模拟物),回收率在87.6%~113.2%之间,相对标准偏差小于10%(n=6)。结论建立了食品接触材料中氯苯和对二氯苯迁移量的气相色谱-质谱联用方法,该方法简单、快捷、准确,满足了食品接触材料中氯苯类物质日常检验的要求。     

啤酒易拉罐中苯酚和双酚A的迁移检测

目的建立一种测定啤酒易拉罐中苯酚和双酚A迁移量的方法,应用于市售易拉罐啤酒污染物的检测。方法选用体积分数为10%的乙醇为食品模拟物,在迁移温度为60℃,迁移时间为10 d的条件下开展迁移研究,采用高效液相色谱-荧光法对迁移样液进行检测。结果在文中的试验方法下,苯酚和双酚A在7 min内可实现完全分离,方法的检出限(LOD)分别为6.0和1.5μg/L。苯酚在20~400μg/L质量浓度范围内线性良好(相关系数为0.9999),双酚A在5~100μg/L质量浓度范围内线性良好(相关系数为0.9998)。通过对空白样品进行加标回收试验,苯酚回收率为90.0%~98.5%,相对标准偏差(RSD)为2.7%~6.2%;双酚A回收率为84.0%~102%,RSD为3.2%~5.3%。将该方法应用于7种易拉罐啤酒中苯酚和双酚A迁移量的检测,结果均未检出苯酚,双酚A检出量在6.9~14.8μg/kg之间。结论该方法准确度高、灵敏度好,能够满足啤酒易拉罐中苯酚和双酚A迁移量检测的要求。     

食品罐内涂膜中有害化学物质的迁移与检测

食品罐内涂膜中有害化学物质主要有双酚A、双酚A二缩水甘油醚、双酚F、双酚F二缩水甘油醚、酚醛清漆甘油醚及其衍生物等,国际上对这些有害化学物质的使用做出了相关限定。常用的食品罐检测前处理方法有液-液萃取法、固相萃取法以及固相微萃取法等,食品罐内涂膜中有害化学物质的检测方法主要有高效液相色谱法、气相色谱-质谱法和酶联免疫法。针对食品罐内涂膜有害物质迁移的研究还存在有害物质毒性机理不健全和检测方法不完善等问题,寻找一种精确、简便且可同时检测多种有害物质的方法,并加强对有害化学物质迁移模型的建立是该领域的研究方向。     

Determination of Four Types of Hazardous Chemicals in Food Contact Materials by UHPLC‐MS/MS

A simple ultrahigh‐performance liquid chromatography (UHPLC) tandem mass spectrometric method for the identification and quantification of two photoinitiators 4‐methylbenzophenone and 2‐ethylhexyl‐4‐dimethylaminobenzoate; nine plasticizers including di(2‐ethylhexyl) adipate and diisobutyl adipate; three primary aromatic amines 4‐aminobiphenyl, 4‐amino‐2′,3‐dimethylazobenzene and bis‐(4‐aminophenyl) methane and six bisphenols bisphenol F diglycidyl ether, bisphenol A diglycidyl ether, bisphenol A (BPA), bisphenol B (BPB), bisphenol E (BPE) and bisphenol F (BPF) in food contact materials has been developed. The chromatographic conditions, pre‐treatment methods and matrix effects were studied and optimized. For the determination of the four bisphenols, BPA, BPB, BPE and BPF, the UHPLC method employed a mobile phase of aqueous ammonia and methanol in binary gradient mode, and measurement was based on a triple quadrupole mass spectrometer equipped with an electrospray ionization (ESI) source operating in negative ion mode. The remaining chemicals were determined using the ESI source in positive ion mode and using the [M + NH₄]⁺ or [M + H]⁺ adducts as precursor ions for tandem mass spectrometry. The calibration graphs were linear with correlation coefficients of above 0.995. Detection limits for the method were in the range of 1–16 µg/kg. Analyte recovery values were in the range of 70–114%, and relative standard deviations were 1–14%. Under optimized conditions, the chromatographic separation was performed in 12 min. The validation data indicated that the method was effective for the determination of the four classes of hazardous chemicals in plastic packaging materials or in can lacquers. The optimized method was successfully applied to trace analysis of commercially available food contact materials. Copyright © 2014 John Wiley & Sons, Ltd.     

氰酸酯/环氧树脂共混物热分解动力学

利用动态TGA方法研究了双酚A二缩水甘油醚环氧树脂和酚醛环氧树脂与双酚A二氰酸酯的两类共混物的热稳定性。用Coats-Redfern研究了不同配比共混物的热分解动力学。结果表明,氰酸酯含量大的双酚A二缩水甘油醚环氧树脂/双酚A二氰酸酯共混物具有两阶段分解机理,而环氧含量大的双酚A二缩水甘油醚环氧树脂/双酚A二氰酸酯共混物具有均一的热分解活化能;相比较而言,酚醛环氧树脂/双酚A二氰酸酯共混物的分解活化能基本上不随温度和组成变化。从后期失重温度和活化能看,酚醛环氧树脂/双酚A二氰酸酯共混物具有比双酚A二缩水甘油醚环氧树脂/双酚A二氰酸酯共混物更高的热稳定性。     

Survey of Food Can Coatings in Thailand – Their Use,Extractable Residues and Migrations

Face‐to‐face interviews with manufacturers of food cans and producers of canned foods in Thailand were performed to collect information in real practice regarding the use of coating resins with respect to packed food types. For export markets, epoxy‐coated cans accounted for 58%, polyvinyl chloride organosol 35% and uncoated 7%. Meanwhile, the respective fractions for domestic markets were 83, 2 and 15%. The identification of coating polymers was confirmed using Fourier transmission infrared technique. It was found that acetonitrile extraction could be used to predetermine the compliance of coated cans before use, provided that the detected amounts are below the limits. Interestingly, the highest levels of bisphenol A diglycidyl ether (BADGE) and its hydrolysed products detected in simulants and 45 canned food samples were factors of 10 to 21 below its SML of 9 mg/kg, and the percentage of samples containing ‘non‐detectable’ levels of BADGE ranging from 10 to 70; of chlorohydroxy BADGE – factors of 3 to 13 below 1 mg/kg, and the percentage of ‘non‐detectable’ ranging from 57 to 85; and of bisphenol A – factors of 32 to 140 below 0.60 mg/kg, and the percentages of ‘non‐detectable’ ranging from 0 to 95. The determination of BADGE and its derivatives was performed on a high‐performance liquid chromatograph with a fluorescence detector, while bisphenol A using a gas chromatography–mass spectrometry technique. All cans and canned food samples extensively complied with European Union regulations and Japanese voluntary standards. Copyright © 2017 John Wiley & Sons, Ltd.     

Migrants from food cans revisited – application of a stochastic model for a more realistic assessment of exposure to bisphenol A diglycidyl ether (BADGE)

We have used a two‐dimensional probabilistic model to estimate the short‐term dietary exposure of UK consumers to bisphenol A diglycidyl ether (BADGE) migrating from light metal food packaging. Using three UK National Dietary and Nutrition Surveys comprising 4–7‐day dietary surveys for different ages and genders, actual body weights and survey years, a sample representative of the UK population was obtained, comprising around 4200 food items. The packaging type of each food item was assigned by utilizing known packaging type from the database or by sampling from a distribution based upon market share information or expert judgement. For concentration data, we have used published data for foods or food simulants or a combination of both. The probabilistic approach allowed sensitivity analysis to evaluate the relative importance of the input parameters and placed confidence bounds on the outputs to show the effect of the uncertainties. The refined estimates gave an exposure for UK consumers, at the 97.5th percentile level, of 0.41–0.83 μ/kg body weight (bw)/day for the different age ranges and scenarios run. All estimates are well below the new tolerable daily intake value of 150 μ/kg bw/day for BADGE and its two hydrolysed forms, and are also well below the restriction value of 17 μ/kg bw/day for the other regulated BADGE derivatives. The main contributors to exposure are beverages, along with aqueous and acidic foods. This is because of the high consumption of these classes of foodstuffs, even though levels of migration into these foodstuffs and into their appropriate simulants is normally non‐detectable. Reducing the non‐detectable level six‐fold reduced the estimate of exposure by 40–60%. Copyright © 2006 John Wiley & Sons, Ltd.     

海因环氧树脂/DDS体系的制备与性能

合成了海因环氧树脂,采用红外光谱和核磁共振进行了表征,制备了海因环氧树脂/二氨基二苯砜(DDS)体系,研究了海因环氧树脂/DDS体系的固化反应特性及固化物的性能。结果表明,树脂体系在100℃~296℃有一放热峰,峰值温度为197℃,140℃的凝胶时间长于42 min,在180℃下仅8 min;树脂浇铸体的氧指数为26.6,弯曲强度为111MPa,弯曲模量为4.14 GPa,冲击强度为14.8 kJ/m2。     

海因环氧树脂/HHPA体系的制备与性能

合成了海因环氧树脂,采用红外光谱和核磁共振进行了表征,以六氢苯酐(HHPA)为固化剂,制备了海因环氧树脂/HHPA体系,研究了海因环氧树脂/HHPA体系的固化反应性及其固化物的性能。结果表明:树脂体系在升温速率为10℃/min的条件下,在90～210℃有一放热峰,峰值温度为152.5℃;100℃下的凝胶时间大于42min,在140℃下为8min;树脂浇铸体的氧指数为23,抗弯强度为122MPa,弯曲模量为2.7GPa,冲击强度为14.9kJ/m2。     

环氧树脂的NM R 表征

用1H、13C 核磁共振波谱对二酚基丙烷环氧树脂E-51、缩水甘油胺型环氧树脂A G-80、脂环族缩水甘油酯TDE-85 的结构进行了表征, 并通过二维COSY 谱及1H-13C 化学位移相关谱对各共振峰进行了指认。      

形状记忆氢化双酚A型环氧树脂的制备与性能

为研究聚丙二醇二缩水甘油醚(JH-230)对热固性形状记忆环氧树脂基本性能的影响,将异佛尔酮二胺(IPDA)与具有不同分子量比的氢化双酚A型环氧树脂(AL-3040)、聚丙二醇二缩水甘油醚(JH-230)共混,经完全固化制备出一种新型的形状记忆氢化双酚A型环氧树脂。借助傅里叶红外光谱仪(FT-IR)、差示扫描量热仪(DSC)、动态热机械分析仪(DMA)和拉伸-回复形状记忆测试分析了热固性形状记忆环氧树脂的分子结构以及JH-230对固化体系玻璃化转变温度、储能模量和形状记忆性能的影响。研究表明,JH-230可以增加固化体系链段的柔韧性;固化体系的玻璃化转变温度与动态模量随JH-230含量的增加而降低;该形状记忆氢化双酚A型环氧树脂体系具有良好的形状记忆性能,且形变完全回复时间随JH-230含量的增加而延长。     

Chemical agent identification by field-based attenuated total reflectance infrared detection and solid-phase microextraction

Attenuated total reflectance Fourier transform infrared (ATR-FT-IR) spectroscopy is used to identify liquid and solid-phase chemicals. This research examines the feasibility of identifying vapor-phase chemicals using a field-portable ATR-FT-IR spectrometer (TravelIR) combined with solid-phase microextraction (SPME). Two nerve agent simulants, diisopropyl methylphosphonate (DIMP) and di-methyl methylphosphonate (DMMP), and three sorbent polymers were evaluated. Each polymer was deposited as a thin film on the instrument's sampling interface to partition and concentrate the simulants from air samples prepared in Tedlar bags. The lowest vapor concentrations identified were 50 ppb (v/v) (DIMP) and 250 ppb (v/v) (DMMP). The ATR-FT-IR instrument demonstrated a linear response at concentrations of 1 ppm (v/v) and below. Increasing the sample exposure time, the sample air velocity, and the film thickness was demonstrated to increase the amount of analyte extracted from the air sample. This research demonstrates that it is feasible to use a portable ATR-FT-IR spectrometer with SPME sampling to detect and identify vapor-phase chemicals.