| Objective:Phthalates plasticizers?PAEs?are widely exist in plastics and food-package materials,which were non-covalently binding with plastic productions.as a result,plasticizers cause seriously environment pollution because of it can be easily migrated into soil and air.In particular,PAEs do harm to reproductive system and hepatorenal function after it leak into human body through the respiratory tract,digestive tract,skin etal.Scattering?SERS?technique can achieve fast,sensitive,in situ real-time detection,the LOD can even reach to single molecule level.Vertically aligned gold nanorods arrays was fabricated by evaporative-induced method at optimal ambient temperature and humidity.Butyl Benzyl Phthalate?BBP?and Di-2-Ethyl Hexyl Phthalate?DEHP?can be fastly and sensitively detected.Anisotropic Au@Ag nanopyramid was shown the highly sensitivity for both BBP and DEHP detection.In practical application,The two different geometry structure of SERS substrate exhibited great potential use.Methods:The four various aspect ratio of gold nanorods was synthesized using typical seed growth methods,And These gold nanorods was self-assembled by evaporative- induced methods at different humidity,The optimal size gold nanorods was self-assembled into vertical aligned gold nanorods arrays at optimal temperature and humidity.The sensitivity and reproducibility of VA-GNRs arrays as SERS substrate was evaluated when MG was chosen as Raman probe molecules.The different concentration of BBP spiked with two kinds of liquor was examined sensitively.Based on previous synthesized triangular nanoplate,silver ions was reduced by ascorbic acid.The surface of triangular nanoplate was coated uniformly by silver shell and unique geometry structure Au@Ag nanopyramid was formed.The sensitivity and reproducibility of Au@Ag nanopyramid was investigated when crystal violate as Raman probe molecules.Various concentration of BBP spiked with two liquors was examined.Results:?1?The aspect ratio of 2.18,3.11,3.72,4.49 of gold nanorods were prepared respectively using typical seed mediated growth methods.The four aspect ratio of gold nanorods all exhibited uniform size distribution and showed well monodispersity.The aspect ratio of 3.72 of gold nanorods as building blocks was self-assembled into vertical aligned gold nanorods arrays at temperature of 30?and relative humidity of96%by evaporative-induced methods.The hexagonal close packed VA-GNRs arranged regularly and closely.2.5±0.75 nm of rod separation lead to rich and efficient hot spots.The result of sensitivity and reproducibility examination were as follows:The LOD for MG reached at 10-8M,the relative standard deviations?RSD?was10.40%.Hence,The SERS substrate of VA-GNRs arrays showed highly sensitivity and good reproducibility and could be used to detect Phthalates plasticizers?PAEs?.The LOD for BBP and DEHP reached at 10-9M?10-7M separately.In practical application,1.3 mg/kg of BBP spiked with two liquors were both successfully detected.?2?The uniform Au@Ag nanopyramid was prepared using CTAC as template based on previous synthesized triangular nanoplates.The LOD for crystal violate reached at 10-8M,and the relative standard deviation was 8.75%.The result showed that Au@AgConclusion:The uniform VA-GNRs arrays were fabricated serving aspect ratio of 3.72of gold nanorods as building blocks and avoided coffee ring effect.The formed VA-GNRs arrays arranged in order densely.Raman signal intensity was increased substantially due to enhanced local electromagnetic originating from coupled surface plasmonic resonance caused by unique geometry configuration,The gaps between adjacent gold nanorods serving as trap well can trap more target,Fast and sensitive detection of Phthalates plasticizers?BBP and DEHP?was achieved,In practical application,VA-GNRs exhibited promising potential use.The uniform Au@Ag nanopyramid was prepared using two step methods,Local electromagnetic fields were greatly enhanced at sharp tips,Phthalates plasticizers?BBP and DEHP?were detected sensitively due to large-scale and dense hot spots.Hence,VA-GNRs arrays as SERS substrate could be applied to food industrial and environment monitoring fields. nanopyramid as SERS substrate has highly sensitivity and good reproducibility,which meet the requirement of Phthalates plasticizers?PAEs?detection.The LOD for BBP and DEHP reached at 10-9M?10-7M separately.The relationship for BBP and DEHP between SERS intensity and logarithmn concentration were both shown good linear correlation,R2 was 0.9544 and 0.9555 for BBP and DEHP respectively.1.3 mg/kg of BBP spiked with two liquors were both detected. |
PDF Full Text Request