Detection of Bacillus cereus Spore Biomarkers Using SERS-Based Cuttlebone-Derived Organic Matrix/Silver Nanoparticles

Abstract

The surface-enhanced Raman scattering (SERS) technique has demonstrated great advantages, such as high sensitivity and minimal equipment requirement. However, its application is largely hindered by high-expense SERS substrates. Here, we develop a low-cost and easily accessible SERS platform based on natural cuttlebone-derived organic matrix (CDOM) for rapid and portable detection of the Bacillus cereus spore biomarker, 2,6-pyridinedicarboxylic acid (DPA). The natural porous structure of CDOM helps achieve a significant load of Ag nanoparticles (AgNPs). By adjusting the amount of NaOH in Tollens' reagent, more uniform AgNPs can be obtained on the surface of CDOM. The pyridine N atom or carboxylic acid O atom of DPA acts on the AgNP surface to produce the characteristic peak of SERS. Meanwhile, internal standard materials are added to resist the instability caused by natural materials. The SERS substrate realized the quantitative detection of DPA within 30 min. The linear range is from 40 to 1000 nM, and the detection limit is 8.62 nM. The sensor can detect bacterial spores in foods, such as milk. This method can be used as a reliable idea and an example for the practical application of biologically derived materials.

Aptamer-Modified Porous Anodized Aluminum Substrate for Rapid and Ultrasensitive Detection of Tetracycline via Surface Enhanced Raman Spectroscopy Couple with Electric Field Enrichment

“…The Raman enhancement factor (EF) of the SERS sensor was calculated, and the obtained EF at 1080 cm –1 was 4.1 × 10 9 , suggesting the excellent performance of the SERS sensor for TC detection . To reveal the enhancement mechanism of the SERS substrate, finite-element method (FEM) simulations were used to simulate the LSPR field of AgNPs (the size of AgNPs is 40 nm, and gap is 2 nm).…”

“…The incubation treatment is a must before the analysis and detection of the targets. However, the incubation treatment takes a long time (>30 min), , which greatly increases the time cost of the SERS sensor. In addition, lower concentrations of targets are difficult to be specifically loaded by these above methods, resulting in poor detection sensitivity for the SERS sensor.…”

“…The Raman enhancement factor (EF) of the SERS sensor was calculated, and the obtained EF at 1080 cm −1 was 4.1 × 10 9 , suggesting the excellent performance of the SERS sensor for TC detection. 38 To reveal the enhancement mechanism of the SERS substrate, finite-element method (FEM) simulations were used to simulate the LSPR field of AgNPs (the size of AgNPs is 40 nm, and gap is 2 nm). As shown in Figure S6, because of the presence of excited localized surface plasmon resonance (LSPR), the Raman scattering enhancement in this system mainly comes from the enhanced electromagnetic (EM) field.…”

Design, Fabrication, and Applications of SERS Substrates for Food Safety Detection: Review

“…The design of SERS substrates should be tailored to the specific target substances. In food safety applications, the target substances can be categorized into two groups: small amount molecules [ 80 , 81 , 82 , 83 , 84 , 85 , 86 , 87 , 88 ] and tiny biomaterials, such as cells [ 89 , 90 , 91 , 92 ], cell walls [ 93 , 94 , 95 , 96 ], and spores [ 97 , 98 , 99 , 100 ]. The key distinction between these two categories lies in their size.…”

“…Molecules are typically smaller than 100 nm and can be accommodated within the hotspot of the SERS substrate [ 80 , 81 , 82 , 83 , 84 , 85 , 86 , 87 , 88 ]. On the other hand, tiny biomaterials are generally larger than 100 nm and cannot fit into the small hotspot of the SERS substrate [ 89 , 90 , 91 , 92 , 93 , 94 , 95 , 96 , 97 , 98 , 99 , 100 ]. Therefore, the size of the target substance is a crucial factor to consider when designing a SERS substrate for different target substances.…”