Novel SPR Chip Enhances Detection of High Refractive Index Biomarkers

Surface Plasmon Resonance (SPR) is a widely used label-free optical sensing technique crucial for detecting molecular interactions in real-time, without the need for fluorescent tags. It's invaluable in drug discovery, environmental monitoring, and medical diagnostics. However, conventional SPR sensors often face limitations in accurately detecting samples with a high refractive index, which can include concentrated protein solutions or certain biological fluids, leading to reduced sensitivity and a narrow detection range. This study addresses this critical limitation by developing a multi working mode SPR chip specifically optimized for high refractive index detection.

The newly developed multi working mode SPR chip demonstrated significantly enhanced performance, particularly for high refractive index samples. It achieved a remarkable 2.5-fold increase in sensitivity compared to traditional single-mode SPR sensors when detecting refractive index changes above 1.38. The detection limit for refractive index units (RIU) was improved by 43%, allowing for more precise measurements of subtle changes. Furthermore, the chip exhibited an extended dynamic range, capable of accurately monitoring samples with refractive indices up to 1.45, representing a 30% expansion over conventional designs. The novel multi working mode SPR chip demonstrated a remarkable 2.5-fold increase in sensitivity compared to conventional single-mode SPR sensors, particularly for samples with refractive indices above 1.38, opening new avenues for challenging biosensing applications. This enhanced performance was attributed to the optimized coupling efficiency and the ability to leverage multiple plasmonic resonances simultaneously, providing a more robust and responsive signal.