Hamlyn Centre for Robotic Surgery , Imperial College London , Bessemer Building, South Kensington Campus, Exhibition Road , Kensington, London SW7 2AZ , U.K.
Keenan Research Centre for Biomedical Science , St. Michael's Hospital , Toronto , Ontario M5B 1W8 , Canada.
ACS Appl Mater Interfaces. 2018 Oct 17;10(41):34886-34904. doi: 10.1021/acsami.8b10590. Epub 2018 Oct 3.
Accurate in vitro molecular-level analysis is an essential step prior to in vivo and clinical application for early diagnosis and cancer treatment. Among the diagnostic techniques, surface-enhanced Raman scattering (SERS) biosensing has shown growing potential due to its noninvasive and real-time characterization of the biomolecules. However, the application of SERS biosensing is mostly limited to the plasmonic noble metals, in the form of either nanoparticles or tips and substrates (fixed probe), on which surface plasmon resonance (SPR) is the prominent enhancement principle. The semiconductor quantum particles have been explored in several optoelectronics applications, but have never been reported to be exploited as a means of surface-enhanced Raman scattering (SERS) for molecular-level and intracellular sensing. Here, we report on the new generation of noble-metal-free SERS probe; Si@SiO quantum probe (Si@SiO Q-probe) whose affinity to functional groups not only imitates a self-driven labeling attribution that enables charge transfer (CT) as an augmented enhancement principle but also its mobile nature in miniaturized scale facilitates endocytosis for in situ live cell biosensing. Moreover, a significant enhancement factor of 10 of rhodamine 6G (R6G) and 10 of glutathione (GSH) at ∼5 × 10 pM concentration has been achieved that is comparable to inherently plasmonic noble metals. Our results showed a capability of the Si@SiO Q-probe to unveil the "biochemical fingerprint" of substantial components of mammalian and cancerous cervical cells, which leads to diagnosis of cervical cancer. These unique attributions of the Si@SiO Q-probe can provide better insight into cell mutation and malignancy.
准确的体外分子水平分析是进行体内和临床应用的必要步骤，可用于早期诊断和癌症治疗。在诊断技术中，表面增强拉曼散射（SERS）生物传感由于能够对生物分子进行非侵入性和实时表征，因此显示出越来越大的潜力。然而，SERS 生物传感的应用主要限于等离子体贵金属，其形式为纳米粒子或尖端和衬底（固定探针），在这些探针上，表面等离子体共振（SPR）是突出的增强原理。半导体量子粒子已经在几种光电应用中得到了探索，但从未有报道将其用作分子水平和细胞内传感的表面增强拉曼散射（SERS）手段。在这里，我们报告了新一代的无贵金属 SERS 探针；Si@SiO 量子探针（Si@SiO Q-probe），其对官能团的亲和力不仅模仿了一种自驱动标记属性，从而使电荷转移（CT）作为增强的增强原理，而且其在小型化尺度上的迁移性还促进了用于原位活细胞生物传感的内吞作用。此外，在约 5×10 pM 浓度下，实现了对罗丹明 6G（R6G）和谷胱甘肽（GSH）的 10 倍增强因子，这可与固有等离子体贵金属相媲美。我们的结果表明，Si@SiO Q-probe 能够揭示哺乳动物和癌变宫颈细胞的重要成分的“生化指纹”，从而可以诊断宫颈癌。Si@SiO Q-probe 的这些独特属性可以提供对细胞突变和恶性肿瘤的更好了解。
