Conjugates of Benzoxazole and GFP Chromophore with Aggregation‐Induced Enhanced Emission: Influence of the Chain Length on the Formation of Particles and on the Dye Uptake by Living Cells. Issue 47 (7th November 2016)

• Record Type: Journal Article
• Authors: Carayon, Chantal; Ghodbane, Abdelhamid; Gibot, Laure; Dumur, Rémy; Wang, Jinhui; Saffon, Nathalie; Rols, Marie‐Pierre; Solntsev, Kyril M.; Fery‐Forgues, Suzanne
• Is Part Of: Small. Volume 12:Issue 47(2016)
• Page Start: 6602
• Page End: 6612
• Publication Date: 2016-11-07
• Subjects: aggregation‐induced emission -- confocal microscopy -- crystals -- dye uptake -- nanoparticles; Nanotechnology -- Periodicals; Nanoparticles -- Periodicals; Microtechnology -- Periodicals; 620.5
• DOI: 10.1002/smll.201602799
• Languages: English
• ISSNs: 1613-6810

Abstract

Abstract : Six conjugates of benzoxazole and green fluorescent protein chromophore that differ by the length of their alkyl chain (from C1 to C16) are investigated. They exhibit rigidofluorochromism and clear aggregation‐induced emission enhancement (AIEE) behavior with emission in the orange–red that is specific to the solid state. A preparation method based on solvent exchange is used to prepare particles. The self‐association properties of these molecules depend on the length of the alkyl chain. Microfibers, platelets, and rounded microparticles are successively obtained by increasing the chain length. The same method is used to prepare nanoparticles (NPs) that are fully characterized. In particular, homogeneous populations of stable NPs measuring around 70 nm are obtained with the analogs whose chains contain four to eight carbon atoms. The behavior with respect to living cells is also influenced by the nature of the compounds. Only the dyes with intermediate hydrophobicity are efficiently uptaken by both normal and tumor cells, and fluorescence only originates from dispersed dye molecules. There is no evidence for incorporation of NPs into cells. This work shows that small variations of the chemical structure must be taken into account for making the best use of AIEE compounds in view of precise applications. Abstract : In aggregation‐induced emission‐active compounds, the length of the alkyl chain governs the self‐association properties and the behavior with respect to living cells. Distinct types of microparticles and well‐defined populations of nanoparticles are obtained via reprecipitation. Fluorescence staining of normal and cancer cells is only observed for compounds that bear a medium‐sized chain.