Reusable, flexible, facile, and economical SERS substrates based on rose petal replicas for pesticide detection

A facile method for the fabrication of cost-effective, scalable, and flexible surface-enhanced Raman scattering substrate, based on natural rose petal is discussed. In this study, the rose petal is used as a template, PDMS as an elastomer, and nano casting approach is used to create the inverted texture of rose. For the fabrication of SERS substrates, Au Nanoparticles is deposited via a self-assembly approach onto the substrate consisting inverted texture of Rose. Morphological view depicts that Au nanoparticles are spherical in shape, well-distributed, and closely packed from the top to bottom, which helps in enhancing the signal strength through the generation of LSPR and hot spots. SERS measurement reveals that the prepared flexible substrates are able to sense lower concentrations of Rhodamine 6G (organic pollutant) and Urea (pesticide). The limit of detection of urea is 10(-11) M with an R-2 (linear correlation coefficient) value of 0.99. The substrate has been used for the detection of urea on tomato surface. Furthermore, it is reusable via using a simple drop-casting method and shows good stability ability even after storage of similar to 4 months. The flexible and structured substrate prepared from natural material may open a new door in the field of facile and fast synthesis of substrates.

Automated summary

A facile method for fabricating cost-effective, scalable, and flexible surface-enhanced Raman scattering substrate based on natural rose petal is discussed in this study. The substrate, created through a nano casting approach using rose petals as a template and PDMS as an elastomer, features an inverted texture. By depositing spherical and well-distributed gold nanoparticles onto the inverted texture, the substrate enhances the signal strength through the generation of local surface plasmon resonance and hot spots. The flexible substrate is capable of sensing low concentrations of organic pollutants and pesticides, and has shown good stability and reusability.