Protein aggregation monitoring in microdisk optofluidic sensor through microcavity enhanced Raman scattering

• Published in: Colloids and surfaces. A, Physicochemical and engineering aspects Physicochemical and engineering aspects, 2023-12, Vol.679, p.132561, Article 132561
• Main Authors: Wang, Weian, Zhang, Jiahe, Ye, Peng, Liu, Wei, Mao, Wangqi, Shi, Zengliang, Cui, Qiannan, Wang, Mingliang, Zhu, Gangyi, Xu, Chunxiang
• Format: Article
• Language: English
• Subjects: amyloid; cellular microenvironment; Dynamic monitoring; Light-matter interactions; lysozyme; nanogold; Optofluidic SERS sensor; Protein aggregation; Raman spectroscopy
• ISSN: 0927-7757; 1873-4359
• DOI: 10.1016/j.colsurfa.2023.132561

Protein aggregation plays a crucial role in amyloid lesions but it is a huge challenge to monitor the slight changing process dynamically. Here, we propose an optofluidic surface-enhanced Raman scattering (SERS) sensing chip. It consists of several microdisks deposited with gold nanoparticles (Au NPs), where the microdisk acts as a whispering gallery microcavity (WGM) for light confinement and the Au NPs generate the localized surface plasma for electromagnetic enhancement. The effects of different stimulus factors on the secondary structure of lysozyme protein are revealed by observing the change of Raman spectroscopy of amide band with the enhancement of light-matter interaction. The optofluidic SERS design illuminates the potential for dynamic sensing of biological fluid and cellular microenvironment on chip. [Display omitted] •Microdisk optofluidic sensor can realize microenvironment sensing on-chip.•The ultra-sensitive detection capability comes from the synergy of WGM and LSPR effects.•It provides a new strategy for monitoring protein aggregation and secondary structure evolution analysis.