Adjustable Intermolecular Interactions Allowing 2D Transition Metal Dichalcogenides with Prolonged Scavenging Activity for Reactive Oxygen Species

作者：Yim DaBin; Kim Ji Eun; Kim Hye In; Yang Jin Kyoung; Kang Tae Woog; Nam Jin; Han Sang Hoon; Jun Byeongsun; Lee Chi Ho; Lee Sang Uck; Kim Jin Woong; Kim Jong Ho

来源：Small, 2018, 14(16): 1800026.

DOI：10.1002/smll.201800026

<jats:title>Abstract</jats:title><jats:p>There is an increasing demand for control over the dimensions and functions of transition metal dichalcogenides (TMDs) in aqueous solution toward biological and medical applications. Herein, an approach for the exfoliation and functionalization of TMDs in water via modulation of the hydrophobic interaction between poly(ε‐caprolactone)‐<jats:italic>b</jats:italic>‐poly(ethylene glycol) (PCL‐<jats:italic>b</jats:italic>‐PEG) and the basal planes of TMDs is reported. Decreasing the hydrophobic PCL length of PCL‐<jats:italic>b</jats:italic>‐PEG from 5000 g mol<jats:sup>−1</jats:sup> (PCL<jats:sub>5000</jats:sub>) to 460 g mol<jats:sup>−1</jats:sup> (PCL<jats:sub>460</jats:sub>) significantly increases the exfoliation efficiency of TMD nanosheets because the polymer–TMD hydrophobic interaction becomes dominant over the polymer–polymer interaction. The TMD nanosheets exfoliated by PCL<jats:sub>460</jats:sub>‐<jats:italic>b</jats:italic>‐PEG<jats:sub>5000</jats:sub> (460‐WS<jats:sub>2</jats:sub>, 460‐WSe<jats:sub>2</jats:sub>, 460‐MoS<jats:sub>2</jats:sub>, and 460‐MoSe<jats:sub>2</jats:sub>) show excellent and prolonged scavenging activity for reactive oxygen species (ROS), but each type of TMD displays a different scavenging tendency against hydroxyl, superoxide, and 2,2′‐azino‐bis(3‐ethylbenzothiazoline‐6‐sulfonic acid) radicals. A mechanistic study based on electron paramagnetic resonance spectroscopy and density functional theory simulations suggests that radical‐mediated oxidation of TMDs and hydrogen transfer from the oxidized TMDs to radicals are crucial steps for ROS scavenging by TMD nanosheets. As‐prepared 460‐TMDs are able to effectively scavenge ROS in HaCaT human keratinocytes, and also exhibit excellent biocompatibility.</jats:p>

• 出版日期2018-4-19