SERS纳米探针对电刺激过程中细胞内产生活性氧的检测

SERS Nanoprobe for the Detection of Reactive Oxygen Species in Cells Produced by Electrostimulus

电刺激是用于细胞内紊乱电活动引起疾病的一类重要治疗方式.在电刺激过程中是否会诱导细胞内活性氧(ROS)水平的改变,以及常规抗氧化抑制药物与电刺激治疗同时运用带来的影响,目前尚未有相关研究.本文设计了一种具有较好生物相容性的金/银核壳纳米棒表面增强拉曼(SERS)活性探针,用于电刺激过程中细胞内产生ROS的检测.将该探针与细胞共孵育,使其内化入细胞,对细胞进行不同时间的电刺激,利用拉曼光谱对SERS探针的信号进行检测.实验结果表明,随着电刺激时间的延长,SERS信号减弱,说明细胞内产生ROS的量明显增加.该传感机制是利用ROS能刻蚀金/银核壳纳米棒的银壳,从而使其变薄引起SERS信号减弱.抗坏血酸(AA)和谷胱甘肽(GSH)两种抗氧化抑制剂类药物与电刺激同时运用时,可观察到它们会对电刺激过程产生的ROS有清除作用.该研究发展了一类用于细胞内ROS检测的光谱方法,也为异常的氧化应激和肿瘤治疗过程中的组合用药提供了建议.

Electrostimulus(ES)is an important therapeutic method for diseases caused by abnormal intracellular electrical activity.Also,ES can induce apoptosis of cells,which is a potential tumor treatment method.At present,there are no relevant studies on the intracellular reactive oxygen species(ROS)levels produced in the process of ES,and what effects will be brought by the simultaneous implementation of conventional antioxidant inhibitor drugs and ES therapy.In this study,a kind of gold/silver core-shell nanorod-based surface-enhanced Raman(SERS)-active probe with good biocompatibility was designed for the detection of intracellular ROS generated during ES.The sensing mechanism realized the quantitative analysis of ROS based on the principle that ROS could etch the silver shell,leading to a decrease of the SERS signal of the SERS probe.The probe was co-incubated with cells and was internalized into cells.The cells were then electrically stimulated for different periods of time.Finally,the signal of the SERS probe was detected in vivo.The experimental results show that the SERS signal weakens with the extension of ES time,indicating that the amount of ROS produced in cells increases significantly.In addition,two antioxida⁃tion inhibitors,ascorbic acid(AA)and glutathione(GSH),were studied when combined with ES.It was observed that they could eliminate reactive oxygen species(ROS)produced by electrical stimulation.This study developed a new method for intracellular ROS detection and suggests a combination of drugs for abnormal oxidative stress and tumor therapy.Also,ES can induce apoptosis of cells,which is a potential tumor treatment method.