Gong Yuting, Li Dong, Chen Min, Lin Anhui, Chen Quansheng, Chen Xiaomei
College of Ocean Food and Biological Engineering, Jimei University, Xiamen, 361021, China.
School of Marine Engineering, Jimei University, Xiamen, 361021, China.
Anal Chim Acta. 2025 Jan 15;1335:343471. doi: 10.1016/j.aca.2024.343471. Epub 2024 Nov 23.
Geosmin (GSM) can compromise the immune systems of aquatic organisms, rendering them more vulnerable to viral and bacterial infections, thereby adversely affecting their growth, reproduction, yield, and quality. Given the relatively low odor thresholds of GSM, there is a critical demand for the development of a highly sensitive and rapid detection method. According to the principle of Surface-enhanced Raman spectroscopy (SERS), localized surface plasmon resonance (LSPR) greatly enhances the Raman signals of adsorbed molecules. To date, no study has reported the application of SERS to detect GSM.
Dual-metal nanomaterials with hollow structures have been proven to provide a large surface area and heightened localized surface plasmon resonance, thereby enhancing the sensitivity of Raman signals. In this study, a sample-to-answer platform was constructed by integrating Au@Ag hollow nanoshells (HNSs)-based SERS and a microfluidic chip for the sensitive, fast, and direct determination of GSM. Under 532 nm excitation, GSM exhibit Raman peaks on the SERS-active Au@Ag HNSs, and there is a relationship between the peak intensity and the concentration of GSM. Owing to the integration of the microfluidic chip, only microliters of reagent are required, and the test results can be achieved within 4 min. The constructed sample-to-answer platform showed a good linear response to GSM in the range of 1 ng/L-1 mg/L, with a detection limit of 0.16 ng/L. An optimal calibration model is established by combining stoichiometric algorithms.
This work realized the ultra-highly sensitive and fast determination of GSM based on SERS-active Au@Ag HNSs, which provides new insights and is very promising for the on-site monitoring of earthy odors. Our study makes a significant contribution to the literature because the developed SERS-based detection method does not require labels or biomaterials, providing the possibility of highly sensitive and on-site testing of contaminants in food and the environment.
土臭素（GSM）会损害水生生物的免疫系统，使其更容易受到病毒和细菌感染，从而对其生长、繁殖、产量和质量产生不利影响。鉴于GSM的气味阈值相对较低，迫切需要开发一种高灵敏度、快速的检测方法。根据表面增强拉曼光谱（SERS）原理，局域表面等离子体共振（LSPR）可极大增强吸附分子的拉曼信号。迄今为止，尚无研究报道将SERS应用于检测GSM。
已证明具有中空结构的双金属纳米材料可提供大表面积并增强局域表面等离子体共振，从而提高拉曼信号的灵敏度。在本研究中，通过整合基于金@银中空纳米壳（HNSs）的SERS和微流控芯片构建了一个样品到答案的平台，用于灵敏、快速且直接地测定GSM。在532nm激发下，GSM在具有SERS活性的金@银HNSs上呈现拉曼峰，且峰强度与GSM浓度之间存在关系。由于微流控芯片的整合，仅需微升试剂，且4分钟内即可获得测试结果。构建的样品到答案平台在1 ng/L - 1 mg/L范围内对GSM表现出良好的线性响应，检测限为0.16 ng/L。通过结合化学计量算法建立了最佳校准模型。
这项工作基于具有SERS活性的金@银HNSs实现了对GSM的超高灵敏度和快速测定，为土腥味的现场监测提供了新见解且极具前景。我们的研究对文献做出了重要贡献，因为所开发的基于SERS的检测方法无需标记或生物材料，为食品和环境中污染物的高灵敏度现场检测提供了可能性。
