Department of Chemical, Materials and Production Engineering, University of Naples "Federico II" , p.le V. Tecchio 80, 80125 Naples, Italy.
CSGI, Consorzio interuniversitario per lo sviluppo dei Sistemi a Grande Interfase, Sesto Fiorentino , via della Lastruccia 3, 50019 Firenze, Italy.
ACS Appl Mater Interfaces. 2017 Nov 1;9(43):37615-37622. doi: 10.1021/acsami.7b11839. Epub 2017 Oct 23.
We disclose herein the first example of stable monodispersed hybrid nanoparticles (termed MelaSil-NPs) made up of eumelanin biopolymer intimately integrated into a silica nanoscaffold matrix and endowed with high antioxidant and cytoprotective effects associated with a specific subcellular localization. MelaSil-NPs have been fabricated by an optimized sol-gel methodology involving ammonia-induced oxidative polymerization of a covalent conjugate of the eumelanin building block 5,6-dihydroxyindole-2-carboxylic acid (DHICA) with 3-aminopropyltriethoxysilanes (APTS). They displayed a round-shaped (ca. 50-80 nm) morphology, exhibited the typical electron paramagnetic resonance signal of eumelanin biopolymers, and proved effective in promoting decomposition of hydrogen peroxide under physiologically relevant conditions. When administered to human ovarian cancer cells (A2780) or cervical cancer cells (HeLa), MelaSil-NPs were rapidly internalized and colocalized with lysosomes and exerted efficient protecting effects against hydrogen peroxide-induced oxidative stress and cytotoxicity.
我们在此披露了首例稳定的单分散杂化纳米颗粒（称为 MelaSil-NPs），其由真黑素生物聚合物紧密集成到二氧化硅纳米支架中，并具有与特定亚细胞定位相关的高抗氧化和细胞保护作用。MelaSil-NPs 是通过一种优化的溶胶-凝胶方法制备的，该方法涉及在氨诱导下对真黑素构建块 5,6-二羟基吲哚-2-羧酸（DHICA）与 3-氨丙基三乙氧基硅烷（APTS）的共价缀合物进行氧化聚合。它们呈现出圆形（约 50-80nm）形态，表现出真黑素生物聚合物的典型电子顺磁共振信号，并在生理相关条件下有效促进过氧化氢的分解。当给予人卵巢癌细胞（A2780）或宫颈癌细胞（HeLa）时，MelaSil-NPs 被迅速内化并与溶酶体共定位，并对过氧化氢诱导的氧化应激和细胞毒性表现出有效的保护作用。
