Tadi Sai Ratnakar, Shenoy Ashwini G, Bharadwaj Anirudh, C S Sreelakshmi, Mukhopadhyay Chiranjay, Sadani Kapil, Nag Pooja
Department of Mechatronics, Manipal Academy of Higher Education, Manipal, Karnataka, 576104, India.
Microbiology, Manipal Academy of Higher Education, Manipal, Karnataka, 576104, India.
F1000Res. 2025 Mar 18;13:670. doi: 10.12688/f1000research.149263.2. eCollection 2024.
The Raman effect originates from spontaneous inelastic scattering of photons by matter. These photons provide a characteristic fingerprint of this matter, and are extensively utilized for chemical and biological sensing. The inherently lower generation of these Raman scattered photons, do not hold potential for their direct use in sensing applications. Surface enhanced Raman spectroscopy (SERS) overcomes the low sensitivity associated with Raman spectroscopy and assists the sensing of diverse analytes, including ions, small molecules, inorganics, organics, radionucleotides, and cells. Plasmonic nanoparticles exhibit localized surface plasmon resonance (LSPR) and when they are closely spaced, they create hotspots where the electromagnetic field is significantly enhanced. This amplifies the Raman signal and may offer up to a 10 -fold SERS signal enhancement. The development of SERS active substrates requires further consideration and optimization of several critical features such as surface periodicity, hotspot density, mitigation of sample or surface autofluorescence, tuning of surface hydrophilicities, use of specific (bio) recognition elements with suitable linkers and bioconjugation chemistries, and use of appropriate optics to obtain relevant sensing outcomes in terms of sensitivity, cross-sensitivity, limit of detection, signal-to-noise ratio (SNR), stability, shelf-life, and disposability. This article comprehensively reviews the recent advancements on the use of disposable materials such as commercial grades of paper, textiles, glasses, polymers, and some specific substrates such as blue-ray digital versatile discs (DVDs) for use as SERS-active substrates for point-of-use (POU) sensing applications. The advancements in these technologies have been reviewed and critiqued for analyte detection in resource-limited settings, highlighting the prospects of applications ranging from single-molecule to single-cell detection. We conclude by highlighting the prospects and possible avenues for developing viable field deployable sensors holding immense potential in environmental monitoring, food safety and biomedical diagnostics.
拉曼效应源于物质对光子的自发非弹性散射。这些光子提供了该物质的特征指纹，被广泛用于化学和生物传感。这些拉曼散射光子的产生量本质上较低，不具备直接用于传感应用的潜力。表面增强拉曼光谱（SERS）克服了与拉曼光谱相关的低灵敏度问题，并有助于检测各种分析物，包括离子、小分子、无机物、有机物、放射性核苷酸和细胞。等离子体纳米颗粒表现出局域表面等离子体共振（LSPR），当它们紧密间隔时，会产生热点，其中电磁场会显著增强。这会放大拉曼信号，并可能提供高达10倍的SERS信号增强。开发SERS活性基底需要进一步考虑和优化几个关键特性，如表面周期性、热点密度、减少样品或表面的自发荧光、调节表面亲水性、使用带有合适连接子和生物共轭化学的特定（生物）识别元件，以及使用适当的光学器件，以在灵敏度、交叉灵敏度、检测限、信噪比（SNR）、稳定性、保质期和一次性使用等方面获得相关的传感结果。本文全面综述了近期在使用一次性材料（如商业级纸张、纺织品、玻璃、聚合物）以及一些特定基底（如蓝光数字多功能光盘（DVD））作为即时检测（POU）传感应用的SERS活性基底方面的进展。对这些技术在资源有限环境中进行分析物检测的进展进行了综述和评价，突出了从单分子检测到单细胞检测等应用的前景。我们通过强调开发在环境监测、食品安全和生物医学诊断中具有巨大潜力的可行现场可部署传感器的前景和可能途径来结束本文。
