Surface Plasmon Resonance Sensor Based on Core-Shell Fe3O4@SiO2@Au Nanoparticles Amplification Effect for Detection of T-2 Toxin

• Published in: Sensors (Basel, Switzerland) Vol. 23; no. 6; p. 3078
• Main Authors: Fan, Lirui, Du, Bin, Pei, Fubin, Hu, Wei, Guo, Aijiao, Xie, Zihao, Liu, Bing, Tong, Zhaoyang, Mu, Xihui, Tan, Wenyuan
• Format: Journal Article
• Language: English
• Published: Basel MDPI AG 13.03.2023; MDPI
• Subjects: Acids; Biosensors; Conjugates; Ethanol; Fe3O4@SiO2@AuNPs nanocomposite; Gold; Iron oxides; Magnetic fields; Molecular weight; Monoclonal antibodies; Nanocomposites; Nanoparticles; Nitrogen; Optical properties; Sensors; SPR-based sensor; Surface plasmon resonance; T-2 toxin detection; Tumor necrosis factor-TNF
• ISSN: 1424-8220; 1424-8220
• DOI: 10.3390/s23063078

In this paper, a core-shell based on the Fe3O4@SiO2@Au nanoparticle amplification technique for a surface plasmon resonance (SPR) sensor is proposed. Fe3O4@SiO2@AuNPs were used not only to amplify SPR signals, but also to rapidly separate and enrich T-2 toxin via an external magnetic field. We detected T-2 toxin using the direct competition method in order to evaluate the amplification effect of Fe3O4@SiO2@AuNPs. A T-2 toxin–protein conjugate (T2-OVA) immobilized on the surface of 3-mercaptopropionic acid-modified sensing film competed with T-2 toxin to combine with the T-2 toxin antibody–Fe3O4@SiO2@AuNPs conjugates (mAb-Fe3O4@SiO2@AuNPs) as signal amplification elements. With the decrease in T-2 toxin concentration, the SPR signal gradually increased. In other words, the SPR response was inversely proportional to T-2 toxin. The results showed that there was a good linear relationship in the range of 1 ng/mL~100 ng/mL, and the limit of detection was 0.57 ng/mL. This work also provides a new possibility to improve the sensitivity of SPR biosensors in the detection of small molecules and in disease diagnosis.