title: Bifunctional electro-optical nanoprobe to real-time detect local biochemical processes in single cells.
abstract: A bifunctional electro-optical nanoprobe with integrated nanoring electrode and optical nanotip was fabricated and investigated to simultaneously detect both electrical and optical signals in real-time with high spatial resolution. Concurrent measurements of the oxidant generation and the intracellular antioxidant levels in single cells correlate the stronger oxidant generation with an altered initial antioxidant response in the breast cancer cells in comparison to the normal ones suggesting that the cell malignancy is associated with the strength of oxidative stress, and the higher antioxidant level may be the cause of the drug resistance. While the optical detection indicates the fluctuation of the intracellular redox homeostasis, the chronoamperometric signals allow quantitative real-time detection of the H₂O₂ release and decay. Furthermore, the nanoscale probe enables localized simultaneous detections thus discovering that activated enzymes responsible for the oxidative stress target at specific membrane regions. This method promises applications in study of the dynamics of important physiological processes, and provides the opportunity to unravel the interplay of various signaling pathways.
authors.affiliation: School of Chemical and Biomedical Engineering, Nanyang Technological University, 70 Nanyang Drive, Singapore 637457, Singapore.
authors.forename: Xin Ting
authors.initials: XT
authors.lastname: Zheng
authors.forename: Weihua
authors.initials: W
authors.lastname: Hu
authors.forename: Houxiao
authors.initials: H
authors.lastname: Wang
authors.forename: Hongbin
authors.initials: H
authors.lastname: Yang
authors.forename: Wei
authors.initials: W
authors.lastname: Zhou
authors.forename: Chang Ming
authors.initials: CM
authors.lastname: Li
mesh_terms: D000975:Antioxidants / Q000378:metabolism; D015374:Biosensing Techniques / Q000295:instrumentation*; D001940:Breast / Q000378:metabolism; D001943:Breast Neoplasms / Q000378:metabolism; D002460:Cell Line; D045744:Cell Line, Tumor; D003199:Computer Systems; D055664:Electrochemical Techniques; D004847:Epithelial Cells / Q000378:metabolism; D005260:Female; D006046:Gold; D006801:Humans; D053768:Metal Nanoparticles; D019255:NADPH Oxidases / Q000037:antagonists & inhibitors; D055096:Optical Devices; D018384:Oxidative Stress
chemical_list: D000975:Antioxidants; D006046:Gold; D019255:NADPH Oxidases