title: Early apoptosis real-time detection by label-free SERS based on externalized phosphatidylserine.
abstract: Apoptosis is a tightly regulated cellular process that plays an essential role in the development, aging, cancer biology, immune response, and pathogenesis of various diseases. Herein, we report a new SERS sensing strategy for in vitro sensitive detection of early apoptotic cells. The principle of this method is to in situ synthesize silver nanoparticles (AgNPs) on the phosphatidylserine (PS) of the apoptotic cell membrane during the early apoptosis, which enables distinguishing normal and apoptotic cells. The total assay time of the presented method is only 10 min, thus being faster, cheaper and simpler than current techniques for the detection of apoptosis. The intrinsic mechanism was verified by different approaches based on externalized phosphatidylserine. In addition, the detection process is real-time and label-free; i.e., the intrinsic SERS spectra from the cellular membrane are directly employed for apoptosis real-time detection, which avoids using additional chemical or biological reagents as external signal indicators. Therefore, our SERS approach may serve as a potentially practical tool for sensitive and real-time detection of early cell apoptosis, complementing the state-of-the-art strategies, e.g. flow cytometry. While further investigation is required to better understand the intrinsic mechanism of the in situ coating method, the current results may provide another choice for real-time detection of early apoptosis.
authors.affiliation: Department of Pharmacy and Guangdong Province Key Laboratory of Pharmacodynamic of Traditional Chinese Medicine & New Drug Research, Jinan University, Guangzhou, Guangdong Province 510632, China. jzjjackson@hotmail.com.
authors.forename: Haibo
authors.initials: H
authors.lastname: Zhou
authors.forename: Qiqin
authors.initials: Q
authors.lastname: Wang
authors.forename: Detian
authors.initials: D
authors.lastname: Yuan
authors.forename: Jinyong
authors.initials: J
authors.lastname: Wang
authors.forename: Yang
authors.initials: Y
authors.lastname: Huang
authors.forename: Huihui
authors.initials: H
authors.lastname: Wu
authors.forename: Jingyi
authors.initials: J
authors.lastname: Jian
authors.forename: Danting
authors.initials: D
authors.lastname: Yang
authors.forename: Ning
authors.initials: N
authors.lastname: Huang
authors.forename: Christoph
authors.initials: C
authors.lastname: Haisch
authors.forename: Zhengjin
authors.initials: Z
authors.lastname: Jiang
authors.forename: Shanze
authors.initials: S
authors.lastname: Chen