Development of a standalone software application for the simulation and optimization of surface plasmon resonance-based biosensors

Surface Plasmon Resonance (SPR) has emerged as a powerful biosensing technique, enabling real-time, label-free detection of target biomolecules with high sensitivity. However, the design and optimization of SPR-based biosensors remain challenging, requiring both theoretical expertise and access to specialized simulation tools. The growing demand for these biosensors highlights the need for advanced features and capabilities, such as automated computation of key biosensing metrics, user interactivity, real-time visualization, and dataset generation for machine learning applications. These capabilities are often lacking or scattered across different existing simulation platforms. To address this gap, we developed ‘SPR-Soft’, a new, standalone, PC-based software application for SPR biosensor simulation and optimization. Based on the Transfer Matrix Method (TMM), SPR-Soft features a user-friendly graphical interface that allows real-time input adjustments, live visualization of reflectivity/transmissivity curves, and automated computation of key performance metrics including sensitivity, Full Width at Half Maximum (FWHM), Detection Accuracy (DA), Figure of Merit (FoM), minimum reflectivity (R min ), and Field Enhancement (FE). Additionally, the software includes a dataset generation module to support machine learning-based applications in biosensor design. SPR-Soft’s accuracy was validated through comparison with published simulation data and benchmarked against existing tools. A case study is also presented, demonstrating the software's capabilities by optimizing a gold-silver alloy-based SPR biosensor, achieving enhanced performance: sensitivity of 342°/RIU, FoM of 53.12/RIU, and R min of 0.017 a.u. This development addresses long-standing limitations in biosensor modelling tools, improves research efficiency, enhances accessibility for non-expert users, and ultimately, supports the United Nations Sustainable Development Goals (SDGs #3 and #9). • Software-based simulation is essential for designing and optimizing plasmonic structures before final fabrication. • We present SPR-Soft , a standalone, PC-based software for simulating and optimizing SPR biosensors. It offers real-time visualization of key performance metrics and addresses key limitations of existing SPR simulation tools. • Built on the Transfer Matrix Method (TMM), the software features an interactive GUI that allows users to intuitively adjust input parameters and instantly observe their impact on sensor performance, accelerating both learning and design iteration. • The platform supports simultaneous optimization of multiple biosensor performance metrics and includes built-in functionality for generating structured datasets to support future machine learning applications such as predictive design, configuration optimization, and performance estimation of SPR biosensors. • The simulation accuracy of SPR-Soft is validated through comparisons with established simulation tools and published data, demonstrating strong agreement and reliable results. • A proposed gold-silver alloy-based biosensor designed using SPR-Soft achieves high sensitivity (342°/RIU), an exceptional figure of merit (53.12/RIU), and low minimum reflectivity (0.017 a.u.), highlighting its potential for real-world applications.