Dual-Shell Fluorescent Nanoparticles for Self-Monitoring of pH-Responsive Molecule-Releasing in a Visualized Way

详细信息    查看全文

• 作者：Lingang Yang ; Chuanfeng Cui ; Lingzhi Wang ; Juying Lei ; Jinlong Zhang
• 刊名：ACS Applied Materials & Interfaces
• 出版年：2016
• 出版时间：July 27, 2016
• 年：2016
• 卷：8
• 期：29
• 页码：19084-19091
• 全文大小：545K
• 年卷期：0
• ISSN：1944-8252

文摘

The rational design and controlled synthesis of a smart device with flexibly tailored response ability is all along desirable for bioapplication but long remains a considerable challenge. Here, a pH-stimulated valve system with a visualized “on–off” mode is constructed through a dual-shell fluorescence resonance energy transfer (FRET) strategy. The dual shells refer to carbon dots and fluorescent molecules embedded polymethacrylic acid (F-PMAA) layers successively coating around a SiO₂ core (ca. 120 nm), which play the roles as energy donor and acceptor, respectively. The total thickness of the dual-shell in the solid composite is ca. 10 nm. The priorities of this dual-shell FRET nanovalve stem from three facts: (1) the thin shell allows the formation of efficient FRET system without chemical bonding between energy donor and acceptor; (2) the maximum emission wavelength of CD layer is tunable in the range of 400–600 nm, thus providing a flexible energy donor for a wide variety of energy acceptors; (3) the outer F-PMAA shell with a pH-sensitive swelling–shrinking (on–off) behavior functions as a valve for regulating the FRET process. As such, a sensitive and stable pH ratiometric sensor with a working pH range of 3–6 has been built by simply encapsulating pH-responsive fluorescein isothiocyanate (FITC) into PMAA; a pH-dependent swelling–shrinking shuttle carrier with a finely controllable molecule-release behavior has been further fabricated using rhodamine B isothiocyanate (RBITC) as the energy donor and model guest molecule. Significantly, the controlled releasing process is visually self-monitorable.