1 Department of Food Science, University of Massachusetts, Amherst, Massachusetts 01003, USA (ORCID: http://orcid.org/0000-0001-8461-5325 [H.C.]); and.
2 School of Food Science and Technology, Jiangxi Agricultural University, Nanchang, 330045, People's Republic of China.
J Food Prot. 2018 Jul;81(7):1087-1092. doi: 10.4315/0362-028X.JFP-17-505.
We developed an innovative approach that couples headspace solid-phase microextraction (SPME) with surface-enhanced Raman spectroscopy (SERS) to detect a volatile pesticide (i.e., fonofos) in a liquid complex matrix (i.e., apple juice). A gold nanoparticles-coated fiber was fabricated by reducing gold(III) on a chemically etched stainless steel wire to extract pesticide, using SPME. The fabricated fibers were then tested by a headspace-SPME method and a dip-SPME method, followed by SERS detection of fonofos in water and apple juice samples. Using the headspace-SPME method, we can detect as low as 5 ppb of fonofos in water and apple juice, compared with the dip-SPME method, which cannot detect lower than 10 ppb in water and 50 ppb in apple juice. This study demonstrated the potential capability of the headspace-SPME-SERS method for rapid (within 30 min) and sensitive detection of volatile and vaporizable compounds in complex matrices. The developed method could be a potential alternative approach to the gas chromatography method. Future work is needed to optimize the fiber by minimizing signal variation, and it should be tested in a variety of targeted compounds and matrices.
我们开发了一种创新的方法，将顶空固相微萃取（SPME）与表面增强拉曼光谱（SERS）相结合，用于检测液体复杂基质（如苹果汁）中的挥发性农药（如蝇毒磷）。通过在化学蚀刻的不锈钢丝上还原三价金来制备涂有金纳米粒子的纤维，以通过 SPME 提取农药。然后通过顶空 SPME 法和浸蘸 SPME 法对制备的纤维进行测试，然后对水样和苹果汁样品中的蝇毒磷进行 SERS 检测。使用顶空 SPME 法，我们可以在水中和苹果汁中检测到低至 5 ppb 的蝇毒磷，而浸蘸 SPME 法则无法在水中检测到低于 10 ppb 的蝇毒磷，在苹果汁中检测到低于 50 ppb 的蝇毒磷。本研究证明了顶空 SPME-SERS 方法在复杂基质中快速（30 分钟内）和灵敏检测挥发性和可挥发化合物的潜力。该方法可能是气相色谱法的一种潜在替代方法。未来需要通过最小化信号变化来优化纤维，并应在各种目标化合物和基质中进行测试。
