羊睾丸和梅花鹿胎盘提取液中锌铜镉的测定

利用火焰原子吸收法直接测定了羊睾丸、梅花鹿肋提取液中锌、铜和的含量，并探讨了透析法和超滤法制备提取对元素含量的影响。这一结果为合理开发羊睾丸、梅花鹿胎盘提供液提供了数据。     

大孔树脂脱除中药水煎液中铅、镉和铜的研究

为探讨D001、D113和D7513种大孔树脂对葛根、毛冬青、乌药和苦参4种中药水煎液中模拟超标的铅、铜和镉离子的脱除效果,将中药水提取液经浓硝酸消化后,采用原子吸收光谱法测定了中药水煎液经大孔树脂处理前后铅、铜和镉的质量浓度变化。结果表明,4种中药水煎液经3种大孔树脂处理后,铅、铜和镉含量都普遍降低。可认为D001、D113与D751都能够显著脱除4种中药水提取液中的铅、铜和镉,尤其对镉的脱除效果最好,对铜的脱除效果相对较差,但脱除率都在58.9%以上;大孔螯合树脂D751的脱除效果最好。     

氢化物发生-原子荧光光谱法测定中草药中的微量铅

采用水煎煮法提取中草药,HNO3-H2O2密闭消解体系消解样品,应用氢化物发生-原子荧光光谱法测定中草药及其提取液中的微量铅;优化了仪器工作及实验条件,荧光强度与Pb质量浓度在0.49～400 μg/L范围内呈线性关系,相关系数:0.9996,检出限:0.49 μg/L;发现部分提取液中Pb量比原中草药样品中Pb量有明显降低.     

5种分散吸附剂对茶叶乙腈提取液组分的吸附作用研究

考察了丙基乙二胺(PSA)、C18、石墨化炭黑(GCB)、氧化铝、弗罗里硅土对茶叶乙腈提取液组分(茶多酚、儿茶素类化合物、咖啡碱和叶绿素)的吸附作用。结果表明:C18和GCB显著降低茶叶乙腈提取液颜色深度;PSA对茶多酚和儿茶素类化合物具有较强的吸附作用,50～200 mg PSA使提取液中茶多酚的含量下降了16.3%～67.7%,其它4种吸附剂使提取液中茶多酚的含量下降了0.33%～20.3%。GCB对提取液中的咖啡碱有较好的吸附效果,50～200 mgGCB使提取液中咖啡碱的含量下降了26.4%～68.2%,其它4种吸附剂使提取液中咖啡碱的含量下降了6.32%～28.6%。另外,PSA对叶绿素a和叶绿素b均有较好的吸附效果,且对叶绿素b的吸附效果比叶绿素a明显。     

孕鼠胎盘膜对混合稀土常乐的屏障作用

为评估混合稀土常乐对人体胚胎的潜在危害, 在光镜和电镜下观察了混合稀土常乐染毒后的胎盘组织, 以了解其在胎盘组织中的存在形式和分布情况, 同时应用电感耦合等离子体质谱法(ICP-MS)检测染毒后的孕鼠血清、胚胎组织提取液和羊水中的稀土含量以确定其能否通过胎盘屏障. 染毒于雌鼠妊娠第六天开始, 每天分别以0.3, 2, 5和20 mg·kg-1混合稀土常乐灌胃, 直至妊娠第十八天. 结果显示: 光镜下, 染毒组胎盘绒毛中毛细血管周围合体细胞滋养层胞质内积聚有许多圆形黑色细小颗粒, 颗粒的多少与染毒剂量呈正相关; 电镜下, 染毒组胎盘绒毛中可见有膜包裹的致密体及合体细胞滋养层细胞内线粒体有不同程度的空泡变和嵴断裂; ICP-MS检测: 孕鼠血清铈的含量随染毒剂量的增加而递增, 染毒组胎儿羊水和孕鼠血清中稀土总量, 只有20 mg·kg-1组与对照组相比有显著增加, 其余各组均无显著差异. 胚胎组织提取液中各组的稀土总含量没有变化. 由此得出结论: 胎盘膜对混合稀土常乐进入胚体有很大的限制作用, 但是, 当混合稀土常乐在胎盘膜中积累增加到一定程度时, 可少量透过胎盘屏障, 进入胚体.     

铜绿微囊藻液中提取叶绿素a作为基准物用于荧光光度法测定叶绿素含量

用乙醇从铜绿微囊藻中提取叶绿素a并用分光光度法测得提取液中叶绿素a的质量浓度为1 902.5μg·L-1,以叶绿素a作为标准物质,用荧光光度法测定叶绿素含量。叶绿素a的质量浓度在30~1 800μg·L-1范围内与荧光强度呈线性关系。试验表明:该提取液在冰箱4℃条件下保存,5h内其荧光值的相对误差为±2.5%;在pH 3~9范围内应用时,荧光值的相对误差为±5.0%;在温度5℃~30℃范围中使用时,荧光值的相对误差为±3.0%,证明提取液的稳定性能满足使用要求。与叶绿素标准品同时测定了5个水样中的叶绿素含量,经t检验所得结果之间无显著差异,说明可用叶绿素a代替叶绿素标准品作为荧光光度法中的基准物质。     

海洋珍珠生物提取液单独与顺铂联合对人宫颈癌Siha细胞的生长抑制作用

为探讨海洋珍珠生物提取液对人宫颈癌Siha细胞体外生长的抑制作用,以及海洋珍珠生物提取液增加Siha细胞对顺铂的敏感性,以期对治疗宫颈癌及其它肿瘤寻找新的治疗药物,体外培养人宫颈癌Siha细胞,分别用海洋珍珠生物提取液、顺铂、海洋珍珠生物提取液加顺铂处理24、48、72 h,采用四甲基偶氮唑蓝(MTT)比色法检测海洋珍珠生物提取液和顺铂及两者联合应用Siha细胞的存活率。结果表明,海洋珍珠生物提取液对Siha细胞的增殖有明显的抑制作用(P0.01),其处理,24、48、72 h的IC50分别为56.26、51.92、48.92μg/mL,顺铂对Siha细胞的24、48、72 h的IC50分别为16.74、4.68、6.69μg/mL;两者合用可大大提高对Siha细胞的抑制作用,比单用海洋珍珠生物提取液或单用顺铂均有明显的提高(P0.01)。提示海洋珍珠生物提取液能抑制Siha细胞的生长,同时能增加Siha细胞对顺铂的敏感性。     

软组织中的铅

软组织中的铅含量与年龄有关 ,在 5种铅含量最高的人体软组织中 ,铅浓度均随年龄而累积 ,40岁或 5 0岁时达到最大值 ,其中 4种组织中的最高平均浓度是出生时或儿童时期平均浓度的 4～ 1 0倍 ,值得注意的是 ,新生儿的软组织中就已存在铅 ,这表明铅可通过胎盘转运。比较孕妇分娩时母体和胎儿的血铅浓度 ,也证明铅可以透过胎盘并蓄积在胎儿体内。许多人发现 ,新生儿血铅水平与母体血铅水平显著相关 ,Ｓｉｋｏｒｓｋｉ (1 988)也发现 ,两者关系极为密切 (ｒ=0 72 1 )。动脉中铅浓度随年龄迅速累积似乎不可理解 ,因为从钙 -铅相伴的观点看 ,青少…     

海洋珍珠生物提取液对人宫颈癌Siha细胞增殖与凋亡作用的影响

为探讨海洋珍珠生物提取液对宫颈癌Siha细胞株增殖和凋亡的影响,采用MTT法检测了细胞增殖情况,在流式细胞仪用Annexin V和PI双染检测了细胞的凋亡率,PI单染法测定了细胞周期,Hoechst 33258/PI荧光染色法观测了Siha细胞的形态学改变,RT-PCR法测定了宫颈癌Siha细胞株内Bcl-2,Bax基因表达。结果表明,海洋珍珠生物提取液在一定质量浓度范围内,以浓度依赖性的方式抑制宫颈癌Siha细胞的生长(P0.05);以0,6,30和60μg/mL海洋珍珠生物提取液处理细胞24 h,Siha细胞早期凋亡率分别为5%,7.1%,32.25%和31.95%,晚期凋亡比例为0.45%,2.85%,8.55%和23.2%;荧光显微镜下细胞呈现典型的凋亡性改变;RT-PCR显示海洋珍珠生物提取液处理后宫颈癌Siha细胞内的Bcl-2 mRNA表达降低,Bax mRNA表达升高。提示海洋珍珠生物提取液以浓度依赖性的方式抑制宫颈癌Siha细胞增殖,并通过降低Bcl-2 mRNA,升高Bax mRNA来诱导细胞凋亡。     

韭菜有机溶剂提取液的气相色谱-质谱分析及其对香蕉枯萎病菌的抑制作用研究

采用气相色谱-质谱法对韭菜茎和叶的石油醚、三氯甲烷、二氯甲烷、丙酮、乙酸乙酯有机溶剂提取液进行了检测.结果表明:有机溶剂提取液中有二甲基二硫、二甲基三硫、甲基甲烷硫代磺酸盐、二甲基酯硫磺酸、甲基2-丙烯基二硫及杂环等多种含硫化合物,另外还检出较复杂的3-乙烯基-1,2-二硫代杂环己-5-烯类物质.低温条件下,茎中石油醚...     

多效皮肤外洗液元素分析

采用原子吸收光谱法（AAS）测定了多效皮肤外洗中的锌、铜、铁、钙、镁等六个元素含量,实验结果表明该药含有丰富的锌、铜、铁、钙、镁等有益元素,有害元素铅含量极微。符合皮肤外洗液要求。     

原子吸收光谱法测定益寿回春口服液中砷铅镉铬汞的含量

采用原子吸收光谱法测定了益寿回春口服液中砷、铅、镉、铬和汞的含量，并参照食品中重金属的限量规定进行了比较。结果表明，益寿回春口服液中的砷、铅、镉、铬和汞均低于限量标准，为该产品的质量控制提供了依据。     

温度对液态重金属Pb结构变化的影响

利用分子动力学模拟技术 ,详细考察了在不同温度下液态金属Pb的结构特点。结果发现液态金属Pb的有序度随温度降低不断增强 ;液态金属Pb中存在着不同类型的原子集团 ,原子集团是以不同类型的键对存在的。利用键对分析技术 ,计算出不同温度下的键对类型数和二十面体的两类键趋向序参数 ,从微观上分析了液体与固体的结构相关性。说明了液态金属在不同温度下有不同的结构形式 ,而不象人们想象得那样杂乱无章。     

青海种植山茛菪根部重金属元素特征

采集2～7年生人工种植山莨菪,用原子荧光光谱仪测定了镉、砷、汞,原子吸收光谱仪测定铅。结果表明,2—7年生种植山莨菪在每年9月份中,4种重金属元素含量水平由高到低依次为：砷、镉、铅、汞;铅和镉、砷和铅、且砷和镉之间均存在一定相关性。各种重金属的含量随着年份和生物量的增加而有所积累。     

Application of microwave-assisted dispersive liquid–liquid microextraction and graphite furnace atomic absorption spectrometry for ultra-trace determination of lead and cadmium in cereals and agricultural products

This study was designed to determine the ultra-trace amounts of lead (Pb) and cadmium (Cd) in various cereals (rice, wheat, barley, peas, beans, corn and lentil) obtained from the markets in Kermanshah city, West Iran. An efficient microextraction method was applied to separation and preconcentration of metal ions. This method is dispersive liquid–liquid microextraction based on solidification of floating organic drop, which overcomes the most important problems of other microextraction techniques. Some effective parameters on extraction were studied and, under optimised conditions, the enhancement factors were 122 and 115 for Cd and Pb, respectively. The calibration graphs were linear in the range of 0.1–50 µg kg^?1 with correlation coefficient more than 0.992. The detection limit was 0.05 µg kg^?1. The values of intra-day relative standard deviations and inter-day relative standard deviations were in the range of 4.7?5.3% and 6.0?6.8%, respectively. The Pb concentrations in rice and wheat samples were considerably higher than the allowable limits set by World Health Organization. The method was successfully applied to determination of the Pb and Cd in cereals, and application of the proposed method to the analysis of two certified reference materials produced results that were in good agreement with the certified values.     

Ionic liquid-based dispersive liquid–liquid microextraction for the separation and preconcentration of lead in water samples prior to FAAS determination without chelating agent

In the present study, an environment-friendly sample preparation method termed ionic liquid-based dispersive liquid–liquid microextraction combined with flame atomic absorption spectrometry has been developed for the determination of Pb(II) ion in water samples prior to flame atomic absorption spectrometry determination. In this method, ionic liquid was used as an extraction solvent instead of the organic solvent used in the conventional dispersive liquid–liquid microextraction (DLLME) assay, and there is no need for a chelating agent. Several variables that may affect extraction efficiencies, including pH, the volume of ionic liquid, the type and volume of disperser solvent, salt addition, and the time for centrifugation and extraction were studied and optimised. Under the optimised conditions, the calibration curve exhibited linearity over the range of 20.0–1000.0 μg L^?1. The enrichment factor and the limit of detection based on 3S_b/m were 35.0 and 5.9 μg L^?1, respectively. Seven replicate determination of a solution containing of 100.0 μg L^?1 Pb(II) ions gave a relative standard deviation of ±2.1%. Finally, the feasibility of the proposed method for Pb(II) determination was assessed by the analysis of certi?ed reference material and various water samples and the satisfactory results were obtained.     

儿童血铅含量与智力关系的探讨

为探讨儿童智力与血铅之间的关系 ,把 30名成绩差的学生作为实验组 ,把同龄 30名成绩好的学生作为对照组 ,将两组的血铅测定值及各组血铅≥ 1 0 μg/dL的人数占总数的百分率 ,进行对照比较。结果表明 ,实验组血铅含量显著高于对照组 (P <0 0 1 ) ,且实验组高血铅的百分率也显著高于对照组 (P <0 0 1 )     

Trace elements determination by energy dispersive X-ray fluorescence (EDXRF) in human placenta and membrane: a comparative study

This work is an application of energy dispersive X-ray fluorescence (EDXRF) as an analytical technique for trace elemental determination in human membrane and placenta and elemental concentrations correlations in both tissues. Whole samples were collected during the delivery from healthy mothers and full-term pregnancies. The age of the mother was between 25 and 40 years old, and the weight of the infants ranged from 2.56 to 4.05 kg. Samples were lyophilised and analysed without any chemical treatment. No significant differences in elemental content of placenta and membrane samples were observed except for Ca. Very low levels of Se, As and Pb were observed in all the analysed samples. Zn, considered as one of the key elements in newborn health, was not significantly different in the analysed samples, all of which originated from healthy mothers and healthy babies. The obtained values agree with the literature except for Ca, which is much higher in the studied samples.     

Evaluation of Formaldehyde in Foundry Waste Sands Using Liquid Chromatography

Abstract

The industrial manufacturing of metallic objects results in a high level of foundry waste sands that may contain toxic compounds such as formaldehyde. The formaldehyde content of foundry waste sands was evaluated by liquid chromatography. Samples were collected during various steps of the industrial processes. Results showed that the phenolic alkaline process generated waste sands with higher formaldehyde content than the furanic process; the highest value was 7.6 × 10^?3% (w/w). In this work, formaldehyde content decreased with time in all of the samples studied, revealing that most formaldehyde was released to the occupational environment.