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.
摘要：
在各种仿生聚合物材料中，聚二甲基硅氧烷（PDMS）由于其独特的固有拉曼信号和韧性而成为表面增强拉曼散射（SERS）的理想基质。为了实现前列腺特异性抗原(PSA)的精确检测,我们提出了一种夹心型SERS活性免疫结构，该结构由PDMS@银纳米颗粒（AgNPs）@ZIF-67仿生膜作为免疫底物和金纳米棒（AuNRs）作为免疫探针组成。由于由仿生表面促进的电磁增强和由ZIF-67实现的化学增强的协同作用,该结构使得能够在10-3至10-9mg/mL的宽范围内对PSA进行超灵敏和选择性的检测。所达到的检测限低至3.0×10-10mg/mL。特别是,2905cm-1处的PDMS基质的固有拉曼信号被用作检测中的潜在内标(IS),实现0.996的高测定系数(R2)值。这种多功能SERS底物介导的免疫测定在前列腺癌的早期诊断中具有巨大的潜力。为临床应用提供了有希望的前景。
