AuGa₂on focused Ga ion beam-fabricated Au nanorod array for trace detection of melamine cyanurate in milk solution

Abstract

Au nanorod arrays were fabricated using a focused gallium (Ga) ion beam (fibAu_NRs) with various levels of Ga ion energy. The formation of AuGa2 on fibAu_NRs was controlled by adjusting the level of Ga ion energy and subsequent heat treatment in order to increase the effect of surface-enhanced Raman scattering (SERS). The SERS enhancement factor of the substrates was evaluated using crystal violet as a molecular test probe. The results show that low-density AuGa2 formation on fibAu_NRs increases the SERS effect, which is likely due to the interjunction charge transfer between Au and AuGa2. An optimized AuGa2 on fibAu_NRs was applied to the trace detection of melamine cyanurate in milk solution with high measured sensitivity.

Gold Nanoparticle-Coated ZrO2-Nanofiber Surface as a SERS-Active Substrate for Trace Detection of Pesticide Residue

“…As an emerging technology, surface-enhanced Raman scattering (SERS) techniques are becoming increasingly widespread and accessible for accurate and specific identification of chemical or microbiological contaminants in foodstuffs [ 6 ]. Over the past decades, the technique of SERS has been well developed as a sensitive and selective method, using, for example, nanostructured surfaces [ 7 ]. When target species with Raman-active modes are adsorbed on a nanostructured surface of noble metal(s), particular peak enhancement can be found in the Raman spectrum.…”

“…These regions can be observed or even predicted using computer simulation and modeling to describe the quantum effect on subnanometer gaps [ 12 ]. Usually, a noble metal surface with the structure of high roughness [ 7 ], edges [ 13 ], hollow cavities [ 14 ], and so on, is advantageous to produce EM as well as surface plasmon [ 15 ]. Strategies for fabricating nanostructures can be categorized as, for example, top-down [ 4 ], bottom-up [ 16 ], combination [ 17 ], and template-assisted techniques [ 18 ].…”

Review on Nanomaterial-Based Melamine Detection

“…Notably, in the main stream these reports displayed complications in their optimization along with the great recoveries and linearity in melamine detection, as summarized in Table 3. The majority of nanowires/nanorods/nanotubes-based composite arrays engaged in melamine detection were attributed to the SERS effect of the substrate fabricated and subjected to the analysis [197][198][199][202][203][204][205][206][207][208]210,211,[213][214][215][216][217]. In contrast, some tactics, such as fluorescence [196], electrochemical [200,201], electrochemiluminescence (ECL) [209], and voltammetry [212] were also employed in the discriminative assay of melamine.…”

Graphene Oxide-Coated Metal–Insulator–Metal SERS Substrates for Trace Melamine Detection

“…Therefore, rapid and unambiguous detection of trace amounts of melamine in food products is of paramount importance. To counteract the adverse effects of melamine, various analytical techniques based on SERS for detecting it in dairy and food products have been developed [ 44 , 45 , 46 , 47 ]. For example, in 2016, Dong et al [ 44 ] used polythymine aptamer-modified Au nanoparticles to decrease the limit of detection down to 8 × 10 −12 M for melamine with the SERS effect.…”