Quantitative SERS Assay on a Single Chip Enabled by Electrochemically Assisted Regeneration: A Method for Detection of Melamine in Milk

Abstract

Reusability of sensors is relevant when aiming to decrease variation between measurements, as well as cost and time of analysis. We present an electrochemically assisted surface-enhanced Raman spectroscopy (SERS) platform with the capability to reverse the analyte–surface interaction, without damaging the SERS substrate, allowing for efficient sensor reuse. The platform was used in combination with a sample pretreatment step, when detecting melamine from milk. We found that the electrochemically enhanced analyte–surface interaction results in significant improvement in detection sensitivity, with detection limits (0.01 ppm in PBS and 0.3 ppm in milk) below the maximum allowed levels in food samples. The reversibility of interaction enabled continuous measurement in aqueous solution and a complete quantitative assay on a single SERS substrate.

Towards practical and sustainable SERS: a review of recent developments in the construction of multifunctional enhancing substrates

“…Examples of other less researched substrate regeneration strategies include the replacement of the enhancing nanoparticles and voltage-induced desorption of analyte molecules through reverse bias or electro-oxidation. [274][275][276][277][278] In summary, different strategies for substrate regeneration come with different advantages and disadvantages. More specifically, treatment with sodium borohydride solution offers a convenient and effective solution for substrate regeneration.…”

Microfluidics and surface-enhanced Raman spectroscopy, a win–win combination?

“…To eliminate the memory effect issue, numerous attempts have been made to recycle SERS substrates using solvents, 248,253 electricity, 124,252,254,255 and UV light 256 for multiple SERS measurements. 124,257 Yan et al proposed a photochemical method to prepare Ag nanostructures inside a microfluidic channel to achieve single-molecule detection of dye molecules.…”

Simultaneous and Accurate Quantification of Multiple Antibiotics in Aquatic Samples by Surface-Enhanced Raman Scattering Using a Ti3C2Tx/DNA/Ag Membrane Substrate

“…Combined with efficient and rapid sample pretreatment technology suitable for SERS analysis, it can not only separate the components of the complex sample matrix to eliminate potential matrix interference − but also realize the enrichment of targets in testing solutions, , which would benefit the simultaneous analysis of multiple targets in complex samples with high detection throughput. , Membrane separation technology uses the selective separation of a membrane to achieve the rapid separation, enrichment, and purification of targets in a sample matrix. In addition, it is convenient to utilize membrane separation technology for the construction of a membrane SERS substrate by simply loading specific nanomaterials on membranes. , Membrane materials (such as Nylon 66, cellulose acetate, etc.)…”