Unlocking the potential of bismuth oxybromide microflowers supported silver nanosphere as a SERS platform for detection of nitrofurantoin

Abstract

The accurate detection of antibiotic residues in the environmental and food samples is crucial for ensuring ecosystem safety and human health. Surface enhanced Raman spectroscopy (SERS) has emerged as a powerful analytical technique due to its specificity and sensitivity. In this study, we present the synthesis of noble-metal/2D-semiconductor composites consisting of silver nanospheres and bismuth oxybromide microflowers (Ag-NSs/BiOBr-MFs) for SERS antibiotic detection of nitrofurantoin (NFT). The characteristics of Ag-NSs/BiOBr-MFs composite was examined using various microscopic and spectroscopic methods. The Ag-NSs/BiOBr-MFs composite exhibits precise quantitative detection of NFT in the concentration range from 10^–4 to 10^–12 M with a good linear relationship. The NFT detection using the Ag-NSs/BiOBr-MFs composite demonstrates superior SERS performance, including an ultralow limit of detection of 1.86 × 10^–12 M and a high enhancement factor of 2.75 × 10¹⁰. The highly effective SERS performance of Ag-NSs/BiOBr-MFs composite is due to the formation of numerous hot spots, the effective charge transfer across wide heterogeneous interface, and the synergistic action of electromagnetic and charge transfer mechanisms. The Ag-NSs/BiOBr-based SERS substrate successfully detects the NFT spiked in actual samples with interference compounds, achieving an ultra-low limit of detection of 3.55 × 10^–12 M. These findings highlight the attractive performance of the Ag-NSs/BiOBr-MFs composite-based SERS platform, which holds great potential for practical applications in sensitive food and environmental detection.