FULL PAPER 1902776 (1 of 10) © 2019 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim www.small-journal.com Anti-VEGF-Aptamer Modified C-Dots—A Hybrid Nanocomposite for Topical Treatment of Ocular Vascular Disorders Asaf Shoval, Amos Markus, Zhixin Zhou, Xia Liu, Rémi Cazelles, Itamar Willner,* and Yossi Mandel* Dr. A. Shoval, Dr. A. Markus, Prof. Y. Mandel School of Optometry and Vision Science Faculty of Life Sciences Bar-Ilan University Ramat-Gan 5290009, Israel E-mail: yossi.mandel@biu.ac.il Dr. A. Shoval, Dr. A. Markus, Prof. Y. Mandel Bar Ilan’s Institute for Nanotechnology and Advanced Materials (BINA) Bar Ilan University Ramat-Gan 5290009, Israel Dr. Z. Zhou, Dr. X. Liu, Dr. R. Cazelles, Prof. I. Willner Institute of Chemistry The Minerva Center for Biohybrid Complex Systems The Hebrew University of Jerusalem Jerusalem 91904, Israel E-mail: Itamar.willner@mail.huji.ac.il The ORCID identification number(s) for the author(s) of this article can be found under https://doi.org/10.1002/smll.201902776. DOI: 10.1002/smll.201902776 1. Introduction Nanomedicine [1,2] represents a rapidly developing research area aiming to apply nanoparticles, such as metallic nanopar- ticles, [3,4] semi-conductive quantum dots [5–7] or carbonous mate- rials, [8,9] such as graphene oxide or nanotubes for sensing, [10–12] imaging, [13,14] stimuli responsive carriers [15] or therapeutic agents. [16,17] Carbon dots (C-dots) have attracted growing interest as a functional nanomaterial due to their unique optical, [18–20] The vascular endothelial growth factor (VEGF) induces pathological angio- genetic ocular diseases. It is a scientific challenge to develop carriers for the controlled release of inhibitors for VEGF present in the back of the eye domain. Carbon dots (C-dots) functionalized with the VEGF aptamer are introduced and the hybrid nanoparticles are used for ocular nanomedicine. The C-dots are applied as effective carriers of the anti-VEGF aptamer across the cornea, yielding therapeutic levels upon topical administration. The hybrids show no toxicity for both in vitro and in vivo murine animal model, and further enable noninvasive intraocular concentration monitoring through the C-dots inherent fluorescence. In addition, the hybrid C-dots effectively inhibit VEGF-stimulated angiogenesis in choroidal blood vessels. This inhibition is comparable to two commercially available anti-VEGF drugs, bevacizumab and aflibercept. The hybrid aptamer- modified C-dots provide a versatile nanomaterial to treat age-related macular degeneration and diabetic retinopathy. Inhibiting Macular Degeneration electronic, [21] and catalytic [22] properties, making them suitable for various appli- cations [23,24] such as sensing, [25–27] bio- sensing, [28,29] imaging, [18,30,31] drug and gene delivery, [32,33] catalysis, [34] electroca- talysis, [35] and photo-electrochemistry. [36] Various methods for synthesizing C-dots have been reported (including hydro- thermal, [37] microwave, [38] or chemical [39] treatment of organic substrates), and spe- cifically the synthesis of different sized C-dots, which revealed tunable lumines- cence features and programmable surface functionalities (e.g., amino, carboxylic acid, aldehyde, or hydroxyl groups) ena- bling further surface modification with molecular or biomolecular ligands. [40,41] Aptamers are sequence-specific nucleic acids that selectively bind low molecular weight ligands or macromolecules. [42,43] Aptamers have been widely applied as functional materials for sensing, [44,45] selective drug delivery [46,47] and the design of DNA nanomachines. [48,49] Specifically, the association of aptamers to proteins is known to inhibit the binding and catalytic properties of proteins, [50] and aptamer-based therapies were recognized. [51,52] One of the interesting potential applications of aptamer may include the inhibitory effect of the anti-vascular endothelial growth factor (VEGF) aptamer on the VEGF induced angiogenetic driven ocular diseases. [53] Indeed, the VEGF aptamer has been recently introduced [54] for treatment by ocular injections in cases of age-related macular degeneration (AMD) and diabetic retin- opathy (DR), leading causes of blindness. Treatment availability for these diseases, however, is limited by the need for repeated intraocular injections [55–70] of anti-VEGF performed by highly qualified personnel, and is accomplished by significant systemic and ocular adverse reactions. [54,60,71–74] Nevertheless, intraocular injections remain the treatment of choice due to the limited pen- etration capability of topically applied drugs. [75–77] Different nano- structures have already been suggested as carriers for the VEGF aptamer and such systems have been used for sensing, [78–80] imaging, [81] and stimulus-responsive drug carriers. [52] In the present study we report on the preparation of sur- face modified anti-VEGF aptamer C-dots, their application as hybrid systems for carrying the aptamer across the corneal structure into the eye cavity and stimulating the release of the aptamer in the presence of VEGF, thereby inhibiting the angiogenesis functions of VEGF in the posterior eye chamber. Small 2019, 1902776