JOURNAL OF FOOD COMPOSITION AND ANALYSIS
·
2024
·
IF 4
Zheng Feng,Peng Zhang,Xue Yang,Xiaowei Guo,Jiamin Yu,Liangguang Du,Jimin Shao,Hui Liang,Hong Jiang
Surface-enhanced Raman spectroscopy (SERS) has great potential for rapid detection of trace levels of pesticides in food. Scientists have much interested in this analytical technique due to its sensitivity, rapid detection, simplicity, and low cost. However, most of researchers are only focusing on the detection of a single pesticide residue . In this paper, we firstly report the simultaneous detection of two pesticide residues in tobacco leaves by using composite SERS substrate of SiO 2 @Ag nanoparticles . The entire analysis time is less than 10 min. The detection results show satisfactory linearity in the range of 0.1–25 mg/kg and 1–25 mg/kg with the limit of detection of 0.1 mg/kg and 1 mg/kg for carbendazim and flumetralin in tobacco samples, respectively. The recovery rates of carbendazim and flumetralin in the tobacco leaves are 85.2 ∼ 112.12 % and 90.38 ∼ 113.42 %, respectively. The detection results also show good uniformity and reproducibility, with a relative standard deviation(RSD) value of 4.4 % between substrates. Our reported substrate combined with portable Raman spectrometer provides a powerful tool for simultaneous detection of multiple pesticide residues for food safety.
研究领域:
分析化学
·
食品安全
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产品关联
DOI
高影响因子
Nanomaterials
·
2021
·Vol. 11
·期 9
·2209
·
IF 5.076
Fengyan Wang,Daxue Du,Shan Liu,Linna Wang,Tifeng Jiao,Zhaopeng Xu,Haiyan Wang
Many studies widely used SiO2@Ag composite nanospheres for surface enhanced Raman scattering (SERS), which mainly contributes to electromagnetic enhancement. In addition to experiments, previous simulations mostly adopted a two-dimensional model in SERS research, resulting in the three-dimensional information being folded and masked. In this paper, we adopted the three-dimensional model to simulate the electric field distribution of SiO2@Ag composite nanospheres. It is found that when the Ag nanoparticles are distributed densely on the surface of SiO2nanospheres, light cannot pass through the upper hemisphere due to the local surface plasmon resonance (LSPR) of the Ag nanoparticles, resulting in the upper hemisphere shielding effect; and if there are no Ag nanoparticles distributed densely on the surface of SiO2nanospheres, the strong LSPR cannot be formed, so the incident light will be guided downward through the whispering gallery mode of the spherical structure. At the same time, we designed relevant experiments to synthesize SiO2@Ag composite nanosphere as SERS substrate and used Rhodamine 6G as a probe molecule to study its SERS performance. This design achieved a significant SERS effect, and is very consistent with our simulation results.Keywords:SERS;LSPR;three-dimensional models;upper hemisphere shielding
研究领域:
材料科学
·
光学
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产品关联
DOI
PubMed
高影响因子
POLYMER TESTING
·
2022
·
IF 4.931
Qiao Li,Guangyi Lin,Su Zhang,Haitong Wang,Jyotishmoy Borah,Yuan Jing,Fumin Liu
In the present scenario of development in technology, the applications of stretchable conductive elastomers in modern electronic equipments have aroused great interest. Non-covalent bonding modification of carbon nanotubes (CNTs) using dopamine has improved the dispersion of CNT@PDA and interfacial interaction with the rubber matrix. The SiO 2 @Ag core-shell particles were prepared by coated with silver nanoparticles (AgNPs) on the surface of SiO 2 using dopamine oxidation self-polymerization and electroless plating process. ESBR composites were prepared by latex co-coagulation method, where CNT@PDA and SiO 2 @Ag were used to develop an 1D-3D synergistic conductive network in ESBR composites. One-dimensional (1D) CNT@PDA were incorporated in three-dimensional (3D) spherical SiO 2 @Ag core-shell particles, which effectively prevented the agglomeration of SiO 2 @Ag and CNT@PDA. Again, 1D CNT@PDA could also be used as bridges to interact with 3D SiO 2 @Ag to develop the charge transfer more effectively in ESBR composites. The optimum electrical conductivity of the ESBR/CNT@PDA/SiO 2 @Ag composites was 0.2 S/cm, which was found to be higher than that of single filler. Moreover, the high electrical conductivity can be controlled at low tensile strain. The mechanical property of ESBR/CNT@PDA/SiO 2 @Ag composite was also improved by 105.4% as compared by ESBR/CNTs. This work provides a new idea for the fabrication of stretchable conductive elastomer composites with high performance.
研究领域:
材料科学
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纳米技术
·
电子工程
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产品关联
DOI
高影响因子
SPECTROCHIMICA ACTA PART A-MOLECULAR AND BIOMOLECULAR SPECTROSCOPY
·
2023
·
IF 4.4
Hui Guo,Xiaohui Ren,Xinyue Song,Xin Li
In this work, we fabricated a 300 nm-sized silver-coated silica (SiO 2 @Ag) SERS substrate. Based on SiO 2 @Ag, we designed SiO 2 @Ag@molecular imprinted polymers (SiO 2 @Ag@MIPs) to realize selectively detection of amoxicillin by coating a molecular imprinted layer averagely thinner than 10 nm on SiO 2 @Ag. The as-prepared SERS-active substrate demonstrates excellent enhancement for amoxicillin as well as the enhancement factors were 1.63 × 10 6 of SiO 2 @Ag@MIPs and 2.97 × 10 5 of SiO 2 @Ag, respectively. The SiO 2 @Ag@MIPs core–shell hybrids as SERS substrates and the minimum detectable concentration of amoxicillin was as low as 2.7 × 10 -9 M, and the detection limit of SiO 2 @Ag was 2.7 × 10 -7 M. The linear relationship between intensities of characteristic peaks and concentrations of amoxicillin was established. Both SiO 2 @Ag and SiO 2 @Ag@MIPs substrates were highly sensitive and could achieve qualitative and semi-quantitative analysis of amoxicillin in aqueous media with good linear correlations. Based on the above, SiO 2 @Ag@MIPs will be conducive to detecting actual samples and expanding the practical application.
研究领域:
分析化学
·
纳米材料科学
·
药物分析
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产品关联
DOI
PubMed
高影响因子
TALANTA
·
2023
·
IF 6.1
Nuo Duan,Yuting Chang,Wenhui Lv,Changxin Li,Chunxia Lu,Zhouping Wang,Shijia Wu
Herein, a SiO 2 @Ag NPs core/shell nanoparticles were synthesized to fabricate a surface-enhanced Raman spectroscopy (SERS) sensor for the simultaneous determination of histamine (HIS) and tyramine (TYR) based on specific aptamer recognition and ratiometric strategy. SiO 2 @Ag NPs with 4-thiosaminophenol (4-ATP) and Nile blue A (NBA) molecules were used as an internal standard (IS) and labeled with aptamers corresponding to HIS and TYR, respectively. Raman reporter molecules ROX and Cy5 labeled complementary DNA (cDNA) were then hybridized with aptamers to form rigid double-stranded DNA. After the HIS and TYR were captured by their aptamers, resulting in the dissociation of cDNA and separated from the SERS substrate. Therefore, the SERS signal intensity at 1503 cm −1 of ROX and 1358 cm −1 of Cy5 tagged on the terminal of cDNA decreased with the concentration of HIS and TYR increasing, while the SERS signal intensity at 1079 cm −1 of 4-APT and 592 cm −1 of NBA on the substrate remain stable. Thus, the concentrations of HIS and TYR can be determined by the I 1503 /I 1079 and I 1358 /I 592 values, respectively. This sensing strategy achieves a lower detection limit of 0.2 ng/mL for HIS and 0.05 ng/mL for TYR, respectively, demonstrating promising applications in sensitive detection of BAs in animal-derived foodstuff.
研究领域:
分析化学
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食品科学
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生物技术
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产品关联
DOI
PubMed
高影响因子
JOURNAL OF NANOSCIENCE AND NANOTECHNOLOGY
·
2020
·Vol. 20
·期 4
·2079-2086
·
IF 1.134
Hu Xiangna,Bian XingZhong,Yu Shaozhou,Dan Kun
A magnetic Fe3O4@SiO2@Ag@COOH nanoparticle (NPs)/Au film was fabricated as an effective surface-enhanced Raman scattering (SERS) substrate through a combination of a solvothermal reaction, the Stöber method and an in-situ reaction. The superparamagnetic
property of Fe3O4@SiO2@Ag and the decoration with –COOH groups allow efficient enrichment and capture of thiabendazole molecules. A large quantity of sub-10 nm gaps emerge when Ag NPs are decorated on the surface of the SiO2 shell, offering
a dramatic electromagnetic field enhancement induced by localized surface plasmon resonance (LSPR). Finite-difference time-domain (FDTD) simulations show that strong near-field enhancement around the gap areas between the Ag NPs and Au film occurs, which is caused by the coupling between the
LSPR of the Ag NPs and surface plasmon polaritons (SPPs) of the Au film. Due to the superparamagnetic property and high electromagnetic field enhancement, the Fe3O4@SiO2@Ag@COOH NPs/Au film as a SERS substrate can detect 1 μg/L thiabendazole in solution,
showing great potential for SERS detection of environmental pollutants.
研究领域:
材料科学
·
环境科学
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DOI
高影响因子
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