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比较芝麻菜和七叶菊与叶面和根部施用铂纳米颗粒的相互作用

Comparison of Arugula (Eruca sativa Mill.) and Escarole (Cichorium endivia L.) Interactions with Foliar- and Root-Applied Platinum Nanoparticles
课程网址: http://videolectures.net/ipssc2017_krajnc_platinum_nanoparticles/  
主讲教师: Eva Krajnc
开课单位: 约瑟夫·斯特凡研究所
开课时间: 2017-05-23
课程语种: 英语
中文简介:
人类纳米颗粒(NP)排放物(例如汽车和工业操作产生的)在可食植物表面的大气沉积对城市地区的食品安全构成威胁。纳米颗粒从根到叶的内化和易位已被研究,但关于叶到根的易位和叶NP相互作用知之甚少。在这项研究中,两种广泛种植和消费的植物物种,具有大叶和不同的叶表面自由能(SFE;润湿性):芝麻菜(Eruca sativa Mill.;低SFE)和七叶草(Cichorium endivia L.;高SFE),通过根暴露于分散在超纯水中的铂纳米粒(在20毫升水中施用1毫克铂纳米粒一次)或叶片(暴露于2L达到5叶生长阶段后,每0.5 cm2叶背和叶近轴表面喷洒一滴[5、50或500 mg/L]。铂是本研究的理想选择,因为其环境丰度低(2.7 ppb)[1],耐溶解,并与人为活动直接相关(例如催化转化器)[2]。在整个暴露期内,通过求解基于超纯水、甘油和二碘甲烷接触角测量的杨氏方程的变化来评估叶面暴露叶片的SFE[3]。通过扫描电子显微镜对叶片Pt-NP吸附模式的分析表明,Pt-NP在芝麻菜叶片上以更大的数量和更聚集/凝聚的状态出现,这与SFE较低时,液滴不太可能扩散并从叶片上滴下的事实相一致。用电感耦合等离子体质谱法对清洗过的根和叶进行铂定量,还发现在所有暴露条件下,芝麻菜的叶铂浓度在统计学上较高,而七叶草的根铂浓度在统计学上较高。在500 mg/L浓度下,两种植物对Pt NP的吸收和从叶到根的转运在统计学上都是显著的(p 0.05). 由于铂具有抗溶解性[2],未暴露植物段中铂的存在被解释为NP形式。这些结果强调了叶片SFE在讨论(可食)叶对NP的保留方面的相关性,并证明了NP从叶吸收和转移到根的可能性。 这项工作得到了ISO-FOOD项目“食品质量、安全和可追溯性同位素技术ERA主席”(批准号621329)的支持。
课程简介: Atmospheric deposition of anthropogenic nanoparticle (NP) emissions (e.g. from automobiles and industrial operations) onto edible plant surfaces is a threat to food safety in urban areas. Nanoparticle internalization and translocation from roots to leaves has been investigated, but less is known about leaf to root translocation and leaf-NP interactions. In this study, two widely cultivated and consumed plant species with large leaves and differing foliar surface free energy (SFE; wettability): arugula (Eruca sativa Mill.; low SFE) and escarole (Cichorium endivia L.; high SFE), were exposed to Pt NPs dispersed in ultrapure water through roots (one application of 1 mg Pt NPs in 20 mL water) or leaves (5 day exposure to 2 L droplets [5, 50, or 500 mg/L] applied per 0.5 cm2 abaxial and adaxial leaf surfaces) upon reaching the 5-leaf growth stage. Platinum was ideal for this study because of its low environmental abundance (2.7 ppb) [1], resistance to dissolution, and direct connection to anthropogenic activity (e.g. catalytic converters) [2]. Throughout the exposure period, SFE of foliar-exposed leaves was evaluated by solving a variation of Young's equation based on contact angle measurements from ultrapure water, glycerol, and diiodomethane [3]. Analysis of foliar Pt NP adsorption patterns by scanning electron microscopy showed that Pt NPs appeared in larger amounts and in a more aggregated/agglomerated state on arugula leaves, consistent with the fact that at low SFE, liquid droplets are less likely to spread out and drip off or down the leaf. Platinum quantification of washed roots and leaves with inductively coupled plasma-mass spectrometry also revealed statistically higher leaf Pt concentrations for arugula, and statistically higher root Pt concentrations for escarole at all exposures. Uptake and translocation of Pt NPs from leaves to roots was statistically significant for both plants at a concentration of 500 mg/L (p  0.05). Since Pt is resistant to dissolution [2], the presence of Pt in unexposed plant segments was interpreted as having been in NP form. The results highlight the relevance of foliar SFE in discussions of NP retention by (edible) leaves and demonstrate the possibility for NP uptake and translocation from leaves to roots. This work is being supported by the ISO-FOOD Project "ERA Chair for Isotope Techniques in Food Quality, Safety and Traceability" (grant No. 621329).
关 键 词: 纳米颗粒; 离子体质谱法; 铂纳米粒
课程来源: 视频讲座网
数据采集: 2021-11-05:zkj
最后编审: 2021-11-05:zkj
阅读次数: 41