The Love-SAW Sensor Array for Rapid and Automatic Detection of Haptoglobin in Saliva

Haptoglobin (HP) has been confirmed in multiple studies to be associated with various lung diseases such as lung cancer, CAP, COPD and COVID-19. To meet the needs of rapid non-invasive screening for lung diseases, saliva analysis has emerged as an alternative to serological testing. In this research, we design an automated system with 8 -channels utilizing the Love-type surface acoustic wave sensor for the detection of HP in saliva. This immunosensor primarily relies on the sandwich immunoassay and self-assembly layer of SPA. Furthermore, signal enhancement is achieved through the utilization of AuNPs and immunogold staining. The preliminary results indicate that the Love-SAW sensor assay demonstrates a good linear range for HP detection from $3.125 \sim 100 ng/mL\left(\mathrm{R}^{2}=0.9298\right.$ in PBS and $R^{2}=0.9301$ in artificial saliva), low limits of detection (LOD) ($1.39 ng/mL$ in PBS and 1.80 ng/mL in artificial saliva) and good specificity. This high-throughput device based on Love-SAW immunosensor is expected to efficiently detect various biomarkers, offering valuable insight for diagnosis and prognosis of lung diseases.