發(fā)布時(shí)間：2018-04-26 03:16

  本文選題：表面增強(qiáng)拉曼散射光譜 + PVA凝膠基底�。� 參考：《西南交通大學(xué)》2015年碩士論文

【摘要】：近年來,對于表面污染物的快速現(xiàn)場分析檢測方法的需求不斷增加,比如在家庭安全和食品安全監(jiān)測方面。但是目前尚且缺乏有力的表面分析測試方法從而限制了表面污染分析的發(fā)展。本文提出了一種新型的表面增強(qiáng)拉曼散射光譜(SERS)基底制備方法,合成的基底由于可形變的特性,可適用于各種粗糙程度的表面污染物分析�；趥鹘y(tǒng)凝膠制備技術(shù),我們利用聚乙烯醇(PVA),使其溶解于銀納米粒子(AgNPs)后與硼砂混合形成凝膠基底。我們討論了可能影響凝膠SERS基底性能的不同影響因素,最終優(yōu)化了凝膠SERS基底的制備條件,包括Ag NPs濃度,PVA濃度,PVA-Ag NPs混合物的濃縮倍數(shù)和硼砂與PVA-Ag NPs混合物的體積比。我們總結(jié)了最佳基底制備過程：首先制備5 mM Ag NPs溶液,然后將其當(dāng)做溶劑溶解PVA顆粒,使得PVA的濃度為4%,然后將PVA-Ag NPs濃縮6倍,與質(zhì)量分?jǐn)?shù)為4%的四硼酸鈉溶液以體積比為10：3的比例混合。然后,選取耐爾藍(lán)(NBA)為探針分子,測試了PVA柔性基底對于不同材料和不同粗糙程度的材料表面的分析性能。結(jié)果發(fā)現(xiàn),載玻片表面的NBA檢出限為0.79pg/3cm2,另外,利用此種PVA柔性SERS基底可以檢測出濃度為100 ppb的NBA(絕對量為0.79 ng/3cm2)溶液污染過后的不同的材料表面的NBA殘留,包括砂紙、棉布、金屬、木頭等。最后,基于所制備的可形變的PVA柔性SERS基底,我們對環(huán)境中真實(shí)表面殘留的農(nóng)藥三唑磷以及非法添加劑蘇丹紅Ⅲ進(jìn)行了測試。利用此種凝膠基底測出的蘋果、橘子、包菜表面三唑磷的最低檢出限都低于國家標(biāo)準(zhǔn)水平(分別為0.2,0.2,0.1 ppm),另外,我們還測試了保存不同時(shí)間后的染色金桔表面殘留蘇丹紅Ⅲ的含量,并用高效液相色譜法對SERS分析結(jié)果進(jìn)行了驗(yàn)證。實(shí)驗(yàn)結(jié)果表明,即使是染色一個(gè)月后,金桔表面殘留的亞ppb水平的蘇丹紅Ⅲ依然可以被快速檢測出(大約2 min,包括取樣時(shí)間)。由于此種分析方法并不需要樣品前處理過程,因此將PVA凝膠基底和便攜拉曼光譜相結(jié)合,可在食品質(zhì)量保障領(lǐng)域得到更廣泛的應(yīng)用。
[Abstract]:In recent years, the demand for rapid field analysis and detection of surface pollutants, such as household safety and food safety monitoring, has been increasing. However, the development of surface pollution analysis is limited by the lack of effective surface analysis methods. A novel surface-enhanced Raman scattering (SERS) substrate is proposed in this paper. Due to its deformable properties, the synthesized substrate can be used for the analysis of surface contaminants of various rough degrees. Based on the traditional gel preparation technology, polyvinyl alcohol (PVA) was used to dissolve it in silver nanoparticles (AgNPs) and then mixed with borax to form a gel substrate. We discussed different factors which may affect the properties of gel SERS substrate, and optimized the preparation conditions of gel SERS substrate, including the concentration of Ag NPs and concentration of PVA-Ag NPs mixture and the volume ratio of borax to PVA-Ag NPs mixture. We summarize the optimal substrate preparation process: first, we prepare 5 mm Ag NPs solution, then dissolve the PVA particles as a solvent, so that the concentration of PVA is 4%, and then concentrate PVA-Ag NPs 6 times. Mixed with 4% sodium tetraborate solution at a volume ratio of 10:3. Then, the analytical properties of PVA flexible substrates for different materials and different rough materials were tested by using Nell blue PVA as probe molecule. The results showed that the detection limit of NBA on the slide surface was 0.79pg / 3cm2.In addition, the PVA flexible SERS substrate could be used to detect NBA residues on the surfaces of different materials, including sandpaper and cotton cloth, after the solution of 100 ppb (absolute amount was 0.79ng / 3cm2). Metal, wood, etc Finally, based on the deformable PVA flexible SERS substrate, the residual pesticide triazophos and the illegal additive Sudan 鈪，

本文編號：1804242