Synergistic enhancement mediated sensitive SERS-based immunoassay of PSA using versatile PDMS@AgNPs@ZIF-67 biomimetic substrates

Hengwei Zhao; Zhihan Liu; Shijiao Fu; Tao Jiang; Kerong Wu

doi:10.1016/j.colsurfb.2024.113963

Synergistic enhancement mediated sensitive SERS-based immunoassay of PSA using versatile PDMS@AgNPs@ZIF-67 biomimetic substrates

Colloids Surf B Biointerfaces. 2024 May 16:239:113963. doi: 10.1016/j.colsurfb.2024.113963. Online ahead of print.

Authors

Hengwei Zhao¹, Zhihan Liu², Shijiao Fu¹, Tao Jiang³, Kerong Wu⁴

Affiliations

¹ School of Physical Science and Technology, Ningbo University, Ningbo, Zhejiang 315211, PR China.
² Department of Urology, Ningbo Clinical Research Center for Urological Disease, The First Affiliated Hospital of Ningbo University, Ningbo University, Ningbo, Zhejiang 315010, PR China.
³ School of Physical Science and Technology, Ningbo University, Ningbo, Zhejiang 315211, PR China. Electronic address: jiangtao@nbu.edu.cn.
⁴ Department of Urology, Ningbo Clinical Research Center for Urological Disease, The First Affiliated Hospital of Ningbo University, Ningbo University, Ningbo, Zhejiang 315010, PR China. Electronic address: fyywukerong@nbu.edu.cn.

PMID: 38759294
DOI: 10.1016/j.colsurfb.2024.113963

Abstract

Among various biomimetic polymer materials, polydimethylsiloxane (PDMS) stands out as an ideal matrix for surface-enhanced Raman scattering (SERS) due to its unique intrinsic Raman signal and tenacity. In order to realize the precise detection of prostate-specific antigen (PSA), we proposed a sandwich-type SERS-active immunostructure composed of PDMS@silver nanoparticles (Ag NPs)@ZIF-67 biomimetic film as the immunosubstrate and gold nanorods (Au NRs) as immunoprobes. Due to the synergistic effect of electromagnetic enhancement facilitated by biomimetic surfaces and chemical enhancement achieved by ZIF-67, this structure enabled an ultrasensitive and selective detection of PSA across a broad range from 10^-3 to 10^-9 mg/mL. The achieved limit of detection was as low as 3.0 × 10^-¹⁰ mg/mL. Particularly, the intrinsic Raman signal of PDMS matrix at 2905 cm^-1 was employed as a potential internal standard (IS) in the detection, achieving a high coefficient of determination (R²) value of 0.996. This multifunctional SERS substrate-mediated immunoassay holds vast potential for early diagnosis of prostate cancer, offering promising prospects for clinical applications.

Keywords: Bioinspired; Gold nanorods; Internal standard; Metal organic framework; SERS-based immunoassay.