为了正常的体验网站,请在浏览器设置里面开启Javascript功能!

对羟基苯甲酸酯

2017-10-25 15页 doc 123KB 15阅读

用户头像

is_212655

暂无简介

举报
对羟基苯甲酸酯对羟基苯甲酸酯 食品防腐剂对羟基苯甲酸乙酯分子印迹聚合物的制备及吸附性能的研究 对羟基苯甲酸乙酯对真菌的抑菌效果很强,多用作抑菌防腐剂,在我国广泛应用于液体制剂及半固体制剂,及食品及化妆品的防腐。但是,有时候食品防腐剂也是一把“双刃剑”,也有可能给人们的健康带来一定的麻烦。在我国,目前食品生产中使用的防腐剂绝大多数都是人工合成的,使用不当会有一定的副作用;有些防腐剂甚至含有微量毒素,长期过量摄入会对人体健康造成一定的损害,甚至可能有致癌作用。本文采用分子印迹技术制备对羟基苯甲酸乙酯分子印迹聚合物,通过填充成固相萃取柱研究了...
对羟基苯甲酸酯
对羟基苯甲酸酯 食品防腐剂对羟基苯甲酸乙酯分子印迹聚合物的制备及吸附性能的研究 对羟基苯甲酸乙酯对真菌的抑菌效果很强,多用作抑菌防腐剂,在我国广泛应用于液体制剂及半固体制剂,及食品及化妆品的防腐。但是,有时候食品防腐剂也是一把“双刃剑”,也有可能给人们的健康带来一定的麻烦。在我国,目前食品生产中使用的防腐剂绝大多数都是人工合成的,使用不当会有一定的副作用;有些防腐剂甚至含有微量毒素,长期过量摄入会对人体健康造成一定的损害,甚至可能有致癌作用。本文采用分子印迹技术制备对羟基苯甲酸乙酯分子印迹聚合物,通过填充成固相萃取柱研究了该印迹聚合物对对羟基苯甲酸乙酯的选择性萃取性能,探讨了它在分离富集该有害成分应用中的可行性。 1 实验部分 1.1 仪器与试剂 日本岛津GC-2010气相色谱仪,UV2450可见--紫外光分光光度计(岛津);XK96-B快速混匀器(姜堰市新康医疗器械有限公司); 气相色谱仪条件,氢火焰离子化检测器(FID),DB-5熔融石英毛细管色谱柱(15 m× 0. 10 mm× 0. 1μm);进样口温度:260 ?;柱温程序:初始柱温160 ?,保持0.2 min;升温速率120?/min,最终温度280?,保持0. 1min。检测器温度290?,载气为H色谱柱线流速50cm /s,检测器氢气流量30mL/min,空气2, 流量300mL/min,尾吹气(N )流量30mL/min,进样体积为1μ L。 2 对羟基苯甲酸乙酯(分析纯,国药集团化学试剂有限公司);α-甲基丙烯酸(分析纯,郑州派尼化学试剂有限公司);偶氮二异丁腈(AIBN,分析纯,上海精细化工科技有限公司);乙二醇二甲基丙烯酸酯(EDMA,分析纯,ACRO公司产品(北京百零威有限公司));其余试剂均为分析纯, 水为去离子二次蒸馏水。EDMA,MAA均减压蒸馏出去阻聚剂后使用。 1.2 分子印迹聚合物的制备 intensive development. (5) have different emphasis: for development, "with development, the emphasis on" way, from space, multiple groups from a single radiation-belt open development. Spatial structure of 2, the prominent cultural city protection elements on the development of the whole city and culture series supporting role, with natural landscapes and green for the background, according to the combined city, urban Group organization structure, set up a decentralized development patterns, building ... Three rivers: the Yangtze, jinsha River and minjiang rivers, cities in three rivers based on development along the Yangtze River, city on the River, River in the city. Multiple groups: the relatively compact area layout, each district consists of multiple groups, and the area has both integrated urban functions, and have their own characteristics and perimeter formation Li Zhuang, Li Zhuangdong characteristic tour area and Hong Kong in group, consists of 17 groups. Band: modern features gathering along the Yangtze River belt. Dvn group in the upper reaches of the jinsha River along the river continues to the East to South stream groups, layout along the city's main commercial, business, administrative, cultural and creative research and development in science and education function of modern service and port equipment manufacturing, liquor, and other features and modern industry. 2.5-2 spatial planning figure 2.6 in Yibin city, Central City urban development vision vision 称取0.083g(0.5mmol)的对羟基苯甲酸乙酯于10mL的甲醇中,振荡使其全部溶解,分别加入0.26ml(3mmol)MAA、1.89ml(10mmol)EDMA和0.03g (0.195mmol) AIBN,用快速混匀器充分振荡使其充分作用,将混合液放入25 mL具塞试管中,超声脱15min,然后充入氮气15min,密封。将其放入60?恒温水浴中加热24h,所得的棒状聚合物粉碎并过75μm筛,用200mL的V(甲醇)?V(乙酸)=4?1的溶液在索氏提取器中抽提24 h除去分子,再用甲醇洗脱,除去乙酸,晾干后60?真空干燥24h,放入干燥器中备用。 与此同时,用同样比例和制取非印迹聚合物(未加模板分子)。 1.3 聚合物的静态吸附试验 称取10份等量的分子印迹聚合物,每份为50mg,分别置于10mL离心管中,加入5mL浓度为1.0 – 100μg/mL的对羟基苯甲酸乙酯的甲醇溶液,室温下振荡, 然后将各混合液转入离心机中离心,取上清液,进气相色谱分析。依据工作曲线计算不同吸附时间对羟基苯甲酸乙酯的浓度。根据结合前后溶液中对羟基苯甲酸乙酯浓度的变化,由方程Q=(C- C )*V/m计算出聚合物对对羟基苯甲酸乙00 酯的结合量Q(μg/g ),绘出结合量Q与吸附时间关系的动力学曲线。依据吸附速率和平衡吸附量衡量不同聚合条件下分子印迹聚合物的特异性吸附性能。Q为聚合物对底物的吸附量, μg/L;C为底物的原始浓度,μg/L;C为吸附后母0 液中底物的浓度,μg/L;V为所取各对羟基苯甲酸乙酯溶液的体积,L。 0 1.4 固相萃取选择性能实验 1.4.1萃取柱的制备 采用湿法装柱: 称取对羟基苯甲酸乙酯印迹聚合物0.15g,加入15mL甲醇制成浆液,装入容量为1mL、直径为8mm的医用玻璃注射器,用玻璃棉填塞上下部,装填均匀后再用30mL甲醇冲洗。 1.4.2选择性萃取方法 制备好的萃取柱依次用10mL甲醇活化,10mL水润湿后,取由蒸馏水配制的浓度为10μg/ml的对羟基苯甲酸(BA),对羟基苯甲酸甲酯(MP),对羟基苯甲intensive development. (5) have different emphasis: for development, "with development, the emphasis on" way, from space, multiple groups from a single radiation-belt open development. Spatial structure of 2, the prominent cultural city protection elements on the development of the whole city and culture series supporting role, with natural landscapes and green for the background, according to the combined city, urban Group organization structure, set up a decentralized development patterns, building ... Three rivers: the Yangtze, jinsha River and minjiang rivers, cities in three rivers based on development along the Yangtze River, city on the River, River in the city. Multiple groups: the relatively compact area layout, each district consists of multiple groups, and the area has both integrated urban functions, and have their own characteristics and perimeter formation Li Zhuang, Li Zhuangdong characteristic tour area and Hong Kong in group, consists of 17 groups. Band: modern features gathering along the Yangtze River belt. Dvn group in the upper reaches of the jinsha River along the river continues to the East to South stream groups, layout along the city's main commercial, business, administrative, cultural and creative research and development in science and education function of modern service and port equipment manufacturing, liquor, and other features and modern industry. 2.5-2 spatial planning figure 2.6 in Yibin city, Central City urban development vision vision 酸乙酯(EP),对羟基苯甲酸丙酯(PP)的混合标准溶液2.0mL,加载至萃取柱上端。然后用3mL V(水)?V(甲醇)=8:2的溶液淋洗,收集淋洗液;然后用3ml甲醇洗脱萃取柱,收集洗脱液按方法以下方法进行分析。 2 结果与讨论 2.1 功能单体的影响 在0.025mmol/L的对羟基苯甲酸乙酯的乙腈溶液中分别加入不同种类不同浓度的功能单体(α-甲基丙烯酸,丙烯酰胺,丙烯腈,丙烯酸,丙烯酸甲酯,丙烯酸丁酯),其中印迹聚合物比上功能单体的摩尔比例分别为1:1,1:5,1:10,1:20,1:30。实验结果明随着各种功能单体浓度的增加, 对羟基苯甲酸乙酯紫外最大吸收波长发生红移,表明模板分子与各个单体之间存在较强的相互作用。而且当各种单体与模板分子的比例固定时,模板分子与α-甲基丙烯酸相互作用最强。 随后,以对羟基苯甲酸乙酯为模板分子,以α-甲基丙烯酸,丙烯酰胺,丙烯腈,丙烯酸,丙烯酸甲酯,丙烯酸丁酯功能单体分别合成印迹聚合物和非印迹聚合物,比较六种聚合物对模板分子的吸附能力。实验结果表明,以α-甲基丙烯酸为功能单体的印迹聚合物对模板分子的吸附能力最强,而且吸附量大于非印intensive development. (5) have different emphasis: for development, "with development, the emphasis on" way, from space, multiple groups from a single radiation-belt open development. Spatial structure of 2, the prominent cultural city protection elements on the development of the whole city and culture series supporting role, with natural landscapes and green for the background, according to the combined city, urban Group organization structure, set up a decentralized development patterns, building ... Three rivers: the Yangtze, jinsha River and minjiang rivers, cities in three rivers based on development along the Yangtze River, city on the River, River in the city. Multiple groups: the relatively compact area layout, each district consists of multiple groups, and the area has both integrated urban functions, and have their own characteristics and perimeter formation Li Zhuang, Li Zhuangdong characteristic tour area and Hong Kong in group, consists of 17 groups. Band: modern features gathering along the Yangtze River belt. Dvn group in the upper reaches of the jinsha River along the river continues to the East to South stream groups, layout along the city's main commercial, business, administrative, cultural and creative research and development in science and education function of modern service and port equipment manufacturing, liquor, and other features and modern industry. 2.5-2 spatial planning figure 2.6 in Yibin city, Central City urban development vision vision 迹聚合物。说明在合成的印迹聚合物中,α-甲基丙烯酸与模板分子相互作用较强,说明了合成的聚合物中存在对模板分子的特意性吸附位点。 2. 2 平衡吸附性能的研究 测定了MIPs在不同浓度的对羟基苯甲酸乙酯溶液中的吸附量,即结合等温线。实验结果见图2-3。比较两曲线可知,随着对羟基苯甲酸乙酯溶液浓度的增加,单位质量分子印迹聚合物的吸附量也增加,并且在60 μg/mL时达到平衡,图中可以看出单位质量印迹聚合物的吸附量远大于非印迹聚合物的吸附量。这表明在印迹过程中,印迹聚合物中存在对模板分子特异的结合位点,模板分子在MIP中留下的印迹空穴及空穴上的活性结合位点决定了MIPs对模板分子的高度亲和力和特意性识别。 intensive development. (5) have different emphasis: for development, "with development, the emphasis on" way, from space, multiple groups from a single radiation-belt open development. Spatial structure of 2, the prominent cultural city protection elements on the development of the whole city and culture series supporting role, with natural landscapes and green for the background, according to the combined city, urban Group organization structure, set up a decentralized development patterns, building ... Three rivers: the Yangtze, jinsha River and minjiang rivers, cities in three rivers based on development along the Yangtze River, city on the River, River in the city. Multiple groups: the relatively compact area layout, each district consists of multiple groups, and the area has both integrated urban functions, and have their own characteristics and perimeter formation Li Zhuang, Li Zhuangdong characteristic tour area and Hong Kong in group, consists of 17 groups. Band: modern features gathering along the Yangtze River belt. Dvn group in the upper reaches of the jinsha River along the river continues to the East to South stream groups, layout along the city's main commercial, business, administrative, cultural and creative research and development in science and education function of modern service and port equipment manufacturing, liquor, and other features and modern industry. 2.5-2 spatial planning figure 2.6 in Yibin city, Central City urban development vision vision 随后进行 Scatchard 分析。其方程为 Q/ C =( Q – Q ) / K其中 Q 为maxd 聚合物对对羟基苯甲酸乙酯的平衡结合量,C为溶液中的平衡浓度,K为结合位d点的平衡离解常数,Q为结合位点的最大表现结合容量。以Q/ C 对Q 作图,max 得到常温下的 Scatchard 曲线: 由图3-16 可以看出, Q/ C 对Q 呈直线关系,解吸系数为0.061mmol/mL,0.04 mmol/mL,这表明在MIPs中存在2种不同的结合位点。由于对羟基苯甲酸乙酯分子中含有一个羟基,一个羰基,这两个基团中的氧原子都可以与α-甲基丙烯酸中羧基上的氢原子形成氢键。根据对羟基苯甲酸乙酯分子的特点,估计模板分子和α-甲基丙烯酸的作用过程如图2-5。 intensive development. (5) have different emphasis: for development, "with development, the emphasis on" way, from space, multiple groups from a single radiation-belt open development. Spatial structure of 2, the prominent cultural city protection elements on the development of the whole city and culture series supporting role, with natural landscapes and green for the background, according to the combined city, urban Group organization structure, set up a decentralized development patterns, building ... Three rivers: the Yangtze, jinsha River and minjiang rivers, cities in three rivers based on development along the Yangtze River, city on the River, River in the city. Multiple groups: the relatively compact area layout, each district consists of multiple groups, and the area has both integrated urban functions, and have their own characteristics and perimeter formation Li Zhuang, Li Zhuangdong characteristic tour area and Hong Kong in group, consists of 17 groups. Band: modern features gathering along the Yangtze River belt. Dvn group in the upper reaches of the jinsha River along the river continues to the East to South stream groups, layout along the city's main commercial, business, administrative, cultural and creative research and development in science and education function of modern service and port equipment manufacturing, liquor, and other features and modern industry. 2.5-2 spatial planning figure 2.6 in Yibin city, Central City urban development vision vision 2.3 分子印迹聚合物的固相萃取选择性能 实验研究了印迹聚合物对四种结构类似的防腐剂的选择性,分子结构见图 2-6。印迹聚合物对四种物质的萃取结果见图2-7。由图2-7可以看出,印迹聚 合物对对羟基苯甲酸乙酯的吸附能力最强,回收率接近100%,说明分子印迹聚 合物对模板分子的吸附具有高度的选择性。图2-8为四种防腐剂的标准混合 intensive development. (5) have different emphasis: for development, "with development, the emphasis on" way, from space, multiple groups from a single radiation-belt open development. Spatial structure of 2, the prominent cultural city protection elements on the development of the whole city and culture series supporting role, with natural landscapes and green for the background, according to the combined city, urban Group organization structure, set up a decentralized development patterns, building ... Three rivers: the Yangtze, jinsha River and minjiang rivers, cities in three rivers based on development along the Yangtze River, city on the River, River in the city. Multiple groups: the relatively compact area layout, each district consists of multiple groups, and the area has both integrated urban functions, and have their own characteristics and perimeter formation Li Zhuang, Li Zhuangdong characteristic tour area and Hong Kong in group, consists of 17 groups. Band: modern features gathering along the Yangtze River belt. Dvn group in the upper reaches of the jinsha River along the river continues to the East to South stream groups, layout along the city's main commercial, business, administrative, cultural and creative research and development in science and education function of modern service and port equipment manufacturing, liquor, and other features and modern industry. 2.5-2 spatial planning figure 2.6 in Yibin city, Central City urban development vision vision 2.4 方法的回收率和精密度 根据上述的试验 , 用自来水配置的含BA,MP,EP,PP的5.0,10.0,20.0μg/mL的混标溶液,在装有0.15g MIP的萃取柱中,以0.2mL/min的流速加载6mL用3 mL V (水):V (甲醇) = 8:2 进行淋洗,再用3mL甲醇洗脱。过程中使用气相色谱进行检测,平行实验3次,测得四种物质的平均回收率在97.0 %-101%之间和RSD范围1.5-5.2,表明此方法对防腐剂对羟基苯甲酸乙酯有较高的选择性。 表 2-1回收率及精密度实验(n=3) -1-1-11 加标浓5μ g/mL 10μ g/mL 20μ g/mL 度 回收率 RSD 回收率 RSD 回收率 RSD 待测物 intensive development. (5) have different emphasis: for development, "with development, the emphasis on" way, from space, multiple groups from a single radiation-belt open development. Spatial structure of 2, the prominent cultural city protection elements on the development of the whole city and culture series supporting role, with natural landscapes and green for the background, according to the combined city, urban Group organization structure, set up a decentralized development patterns, building ... Three rivers: the Yangtze, jinsha River and minjiang rivers, cities in three rivers based on development along the Yangtze River, city on the River, River in the city. Multiple groups: the relatively compact area layout, each district consists of multiple groups, and the area has both integrated urban functions, and have their own characteristics and perimeter formation Li Zhuang, Li Zhuangdong characteristic tour area and Hong Kong in group, consists of 17 groups. Band: modern features gathering along the Yangtze River belt. Dvn group in the upper reaches of the jinsha River along the river continues to the East to South stream groups, layout along the city's main commercial, business, administrative, cultural and creative research and development in science and education function of modern service and port equipment manufacturing, liquor, and other features and modern industry. 2.5-2 spatial planning figure 2.6 in Yibin city, Central City urban development vision vision 对羟基苯甲酸 97.0% 5.2 99.0% 3.2 100% 1.5 对羟基苯甲酸甲98.2% 3.6 98.8% 3 99.0% 2.8 酯 对羟基苯甲酸乙100.2% 1.5 100.8% 1.7 101% 1.9 酯 对羟基苯甲酸丙99.0% 3.9 99.5% 2.8 99.8% 2.5 酯 3. 结论 研究了以对羟基苯甲酸乙酯分子印迹聚合物的制备及吸附性能。通过Scatchard分析说明印迹聚合物具有两类结合位点。方法具有较高的回收率97.0 %-101%之间和较低的RSD1.5-5.2。结果表明MISPE 柱对模板分子具有较高的选择性,是理想的固相萃取填料,以解决目前对羟基苯甲酸乙酯检测中面临的难. intensive development. (5) have different emphasis: for development, "with development, the emphasis on" way, from space, multiple groups from a single radiation-belt open development. Spatial structure of 2, the prominent cultural city protection elements on the development of the whole city and culture series supporting role, with natural landscapes and green for the background, according to the combined city, urban Group organization structure, set up a decentralized development patterns, building ... Three rivers: the Yangtze, jinsha River and minjiang rivers, cities in three rivers based on development along the Yangtze River, city on the River, River in the city. Multiple groups: the relatively compact area layout, each district consists of multiple groups, and the area has both integrated urban functions, and have their own characteristics and perimeter formation Li Zhuang, Li Zhuangdong characteristic tour area and Hong Kong in group, consists of 17 groups. Band: modern features gathering along the Yangtze River belt. Dvn group in the upper reaches of the jinsha River along the river continues to the East to South stream groups, layout along the city's main commercial, business, administrative, cultural and creative research and development in science and education function of modern service and port equipment manufacturing, liquor, and other features and modern industry. 2.5-2 spatial planning figure 2.6 in Yibin city, Central City urban development vision vision
/
本文档为【对羟基苯甲酸酯】,请使用软件OFFICE或WPS软件打开。作品中的文字与图均可以修改和编辑, 图片更改请在作品中右键图片并更换,文字修改请直接点击文字进行修改,也可以新增和删除文档中的内容。
[版权声明] 本站所有资料为用户分享产生,若发现您的权利被侵害,请联系客服邮件isharekefu@iask.cn,我们尽快处理。 本作品所展示的图片、画像、字体、音乐的版权可能需版权方额外授权,请谨慎使用。 网站提供的党政主题相关内容(国旗、国徽、党徽..)目的在于配合国家政策宣传,仅限个人学习分享使用,禁止用于任何广告和商用目的。

历史搜索

    清空历史搜索