Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, Uttar Pradesh, 201002, India.
CSIR-Central Scientific Instruments Organization (CSIR-CSIO), Sector 30C, Chandigarh, 160030, India.
Sci Rep. 2023 Mar 31;13(1):5297. doi: 10.1038/s41598-023-31152-3.
L-cysteine conjugated molybdenum disulphide (MoS) nanosheets have been covalently attached to a gold coated surface plasmon resonance (SPR) optical fiber to prepare a robust and stable sensor. Owing to the multifunctionality of the deposited nanosheet conjugate, the antibodies are also covalently conjugated in the subsequent step to realize the design of a SPR optical fiber biosensor for the two important bioanalytes namely, Ferritin and Immunoglobin G (IgG). The different stages of the biosensor preparation have been characterized and verified with microscopic and spectroscopic techniques. A uniform and stable deposition of the L-cysteine/MoS nanosheets has allowed the biosensor to be reused for multiple times. Unlike the peeling-off of the MoS coatings from the gold layer reported previously in the case of physically adsorbed nanomaterial, the herein adopted strategy addresses this critical concern. It has also been possible to use the single SPR fiber for both Ferritin and IgG bioassay experiments by regenerating the sensor and immobilizing two different antibodies in separate steps. For ferritin, the biosensor has delivered a linear sensor response (SPR wavelength shifts) in the concentration range of 50-400 ng/mL, while IgG has been successfully sensed from 50 to 250 µg/mL. The limit of detection for Ferritin and IgG analysis have been estimated to be 12 ng/mL and 7.2 µg/mL, respectively. The biosensors have also been verified for their specificity for the targeted molecule only. A uniform and stable deposition of the nanomaterial conjugate, reproducibility, regeneration capacity, a good sensitivity, and the specificity can be highlighted as some of key features of the L-cysteine/MoS optical fiber biosensor. The system can be advocated as a useful biosensor setup for the sensitive biosensing of Ferritin and IgG.
L-半胱氨酸修饰的二硫化钼纳米片通过共价键连接到金涂覆的表面等离子体共振（SPR）光纤上，以制备坚固且稳定的传感器。由于沉积纳米片缀合物的多功能性，抗体也在随后的步骤中通过共价键连接，从而实现了用于两种重要生物分析物即铁蛋白和免疫球蛋白 G（IgG）的 SPR 光纤生物传感器的设计。通过显微镜和光谱技术对生物传感器制备的不同阶段进行了特征和验证。L-半胱氨酸/MoS 纳米片的均匀和稳定沉积使传感器能够重复使用多次。与以前报道的物理吸附纳米材料中从金层剥落 MoS 涂层的情况不同，采用的策略解决了这一关键问题。通过在单独的步骤中再生传感器并固定两种不同的抗体，也可以使用单个 SPR 光纤进行铁蛋白和 IgG 生物分析实验。对于铁蛋白，传感器在 50-400ng/mL 的浓度范围内提供了线性传感器响应（SPR 波长位移），而 IgG 则可以从 50 至 250μg/mL 成功检测到。铁蛋白和 IgG 分析的检测限分别估计为 12ng/mL 和 7.2μg/mL。生物传感器也已通过仅针对目标分子的特异性进行了验证。纳米材料缀合物的均匀和稳定沉积、重现性、再生能力、良好的灵敏度和特异性可以突出 L-半胱氨酸/MoS 光纤生物传感器的一些关键特征。该系统可以作为用于铁蛋白和 IgG 灵敏生物传感的有用生物传感器设置。
