title: Self-Assembled Gold Nanoclusters for Bright Fluorescence Imaging and Enhanced Drug Delivery.
abstract: Nanoparticles combining enhanced cellular drug delivery with efficient fluorescence detection are important tools for the development of theranostic agents. Here, we demonstrate this concept by a simple, fast, and robust protocol of cationic polymer-mediated gold nanocluster (Au NCs) self-assembly into nanoparticles (NPs) of ca. 120 nm diameter. An extensive characterization of the monodisperse and positively charged NPs revealed pH-dependent swelling properties, strong fluorescence enhancement, and excellent colloidal and photostability in water, buffer, and culture medium. The versatility of the preparation is demonstrated by using different Au NC surface ligands and cationic polymers. Steady-state and time-resolved fluorescence measurements give insight into the aggregation-induced emission phenomenon (AIE) by tuning the Au NC interactions in the self-assembled nanoparticles using the pH-dependent swelling. In vitro studies in human monocytic cells indicate strongly enhanced uptake of the NPs compared to free Au NCs in endocytic compartments. The NPs keep their assembly structure with quite low cytotoxicity up to 500 μg Au/mL. Enhanced drug delivery is demonstrated by loading peptides or antibodies in the NPs using a one-pot synthesis. Fluorescence microscopy and flow cytometry confirmed intracellular colocalization of the biomolecules and the NP carriers with a respective 1.7-fold and 6.5-fold enhanced cellular uptake of peptides and antibodies compared to the free biomolecules.
authors: NanoBioPhotonics, Institut d'Electronique Fondamentale, Université Paris-Saclay, Université Paris-Sud , CNRS, 91400 Orsay, France.
authors: Akram
authors: A
authors: Yahia-Ammar
authors: Therapeutic Nanosystems, The Andalusian Centre for Nanomedicine and Biotechnology, BIONAND , 29590 Málaga, Spain.
authors: Daniel
authors: D
authors: Sierra
authors: Laboratoire de Chimie Physique, Université Paris-Saclay and Université Paris-Sud , CNRS, 91400 Orsay, France.
authors: Fabienne
authors: F
authors: Mérola
authors: NanoBioPhotonics, Institut d'Electronique Fondamentale, Université Paris-Saclay, Université Paris-Sud , CNRS, 91400 Orsay, France.
authors: Niko
authors: N
authors: Hildebrandt
authors: Therapeutic Nanosystems, The Andalusian Centre for Nanomedicine and Biotechnology, BIONAND , 29590 Málaga, Spain.
authors: Xavier
authors: X
authors: Le Guével
mesh_terms: D000906:Antibodies / Q000008:administration & dosage*; D002460:Cell Line; D004337:Drug Carriers / Q000009:adverse effects / Q000737:chemistry*; D006046:Gold / Q000737:chemistry; D006801:Humans; D053768:Metal Nanoparticles / Q000009:adverse effects / Q000737:chemistry*; D008856:Microscopy, Fluorescence / Q000379:methods; D009842:Oligopeptides / Q000008:administration & dosage*; D011073:Polyamines / Q000009:adverse effects / Q000737:chemistry; D000071228:Polyelectrolytes; D014466:Ultraviolet Rays
chemical_list: D000906:Antibodies; D004337:Drug Carriers; D006046:Gold; D009842:Oligopeptides; D011073:Polyamines; D000071228:Polyelectrolytes
keywords: aggregation-induced-emission; delivery system; fluorescence enhancement; gold nanoclusters; nanogel; self-assembly