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Aouidat F, Boumati S, Khan M, Tielens F, Doan BT, Spadavecchia J. Int J Nanomedicine. 2019;14:9309–9324. The Editor and Publisher of International Journal of Nanomedicine wish to retract the published article. The authors raised concerns regarding errors that had been made during the calculation of the size of the nanostructures shown in Figure 2. The sizes reported in the histograms of Figure 2; a1, a2 and a3 were incorrect due to miscalculations that occurred during analysis of the gold core and polymer shells of the spherical nanostructures represented in TEM images of Figure 2A. The authors provided the editor with data from the original study and requested to remove the incorrect histograms and replace them. However, the Editor determined that this part of the article was integral to the study and the admission of these errors, because of the miscalculation, meant the data was unreliable and would not accept the correction proposed by the authors. The Editor requested for the article to be retracted and the authors were notified but do not agree with this decision. Our decision-making was informed by our policy on publishing ethics and integrity and the COPE guidelines on retraction. The retracted article will remain online to maintain the scholarly record, but it will be digitally watermarked on each page as “Retracted”.

Fatima Aouidat,1 Sarah Boumati,2 Memona Khan,1 Frederik Tielens,3 Bich-Thuy Doan,2 Jolanda Spadavecchia1 1CNRS, UMR 7244, CSPBAT, Laboratory of Chemistry, Structures and Properties of Biomaterials And Therapeutic Agents University Paris 13, Sorbonne Paris Cité, Bobigny, France; 2UTCBS – Chimie ParisTech – University Paris Descartes - CNRS UMR 8258 – INSERM U1022 Equipe “Synthesis, Electrochemistry, Imaging and Analytical Systems for Diagnostics” SEISAD, Paris, France; 3General Chemistry (ALGC), Vrije University of Brussel (Free University Brussels-VUB), Brussel, BelgiumCorrespondence: Jolanda Spadavecchia Email jolanda.spadavecchia@univ-paris13.frIntroduction: The development of biopolymers for the synthesis of Gd(III) nanoparticles, as therapeutics, could play a key role in nanomedicine. Biocompatible polymers are not only used for complex monovalent biomolecules, but also for the realization of multivalent active targeting materials as diagnostic and/or therapeutic hybrid nanoparticles. In this article, it was reported for the first time, a novel synthesis of Gd(III)–biopolymer–Au(III) complex, acting as a key ingredient of core-shell gold nanoparticles (Gd(@AuNPs).Material and methods: The physical and chemical evaluation was carried out by spectroscopic analytical techniques (Raman spectroscopy, UV-visible and TEM). The theoretical characterization by DFT (density functional theory) analysis was carried out under specific conditions to investigate the interaction between the Au and the Gd precursors, during the first nucleation step. Magnetic features with relaxivity measurements at 7T were also performed as well as cytotoxicity studies on hepatocyte cell lines for biocompatibility studies. The in vivo detailed dynamic biodistribution studies in mice to characterize the potential applications for biology as MRI contrast agents were then achieved.Results: Physical–chemical evaluation confirms the successful design and reaction supposed. Viabilities of TIB-75 (hepatocytes) cells were evaluated using Alamar blue cytotoxic tests with increasing concentrations of nanoparticles. In vivo biodistribution studies were then accomplished to assess the kinetic behavior of the nanoparticles in mice and characterize their stealthiness property after intravenous injection.Conclusion: We demonstrated that Gd@AuNPs have some advantages to display hepatocytes in the liver. Particularly, these nanoconjugates give a good cellular uptake of several quantities of Gd@NPs into cells, while preserving a T1 contrast inside cells that provide a robust in vivo detection using T1-weighted MR images. These results will strengthen the role of gadolinium as complex to gold in order to tune Gd(@AuNPs) as an innovative diagnostic agent in the field of nanomedicine.Keywords: Gd-gold complex, theoretical study, MRI, relaxivity, biodistribution

Galectins (Gal) are a family of dimeric lectins, composed by two galactoside-binding sites implicated in the regulation of cancer progression and immune responses. In this study, we report for the first time the synthesis and the physical-chemical characterization of galectin-1-complex-gold COOH-terminated polyethlenglicole (PEG)-coated NPs (Gal-1 IN PEG-AuNPs) and their ability to recognize glucose in an aqueous solution with a concentration varying from 10 mM to 100 pM. The chemical protocol consistsof three steps: (i) complexation between galectin-1Gal-1 and tetrachloroauric acid (HAuCl 4 ) to form gold-protein grains; (ii) staking process of COOH-terminated polyethlenglicole molecules (PEG) onto Gal-1-Au complex and (iii) reduction of hybrid metal ions to obtain a colloidal stable solution. During the complexation, the spectral signatures related to the Gal-1 orientation on the gold surface have been found to change due to its protonation state. The effective glucose monitoring was detected by UV-vis, Raman spectroscopy and Transmission Electron Microscopy (TEM). Overall, we observed that the interaction is strongly dependent on the Gal-1 conformation at the surface of gold nanoparticles., (Copyright © 2019 Elsevier B.V. All rights reserved.)

In this study, we report, for the first time, the synthesis of two original nanosystems, based on gold Au(III) and copper Cu(II): simple gold-copper nanoparticles (Cu 0 AuNPs) and enriched monopicolinate cyclam (L1)-Cu(II)-Au(III)-complex (L1@Cu 2+ AuNPs). The two nanomaterials differ substantially by the chelation or not of the Cu(II) ions during the NPs synthesis process. The two hybrid nanoparticles (Cu 0 AuNPs; L1@Cu 2+ AuNPs) were deeply studied from the chemical and physical point of view, using many different analytical techniques such as Raman and UV-vis spectroscopy, electron transmission microscopy, and dynamic light scattering. Both nanosystems show morphological and good chemical stability at pH 4 values and in physiological conditions during 98 h. Undifferentiated and neural differentiated murine embryonic stem cells were used as a model system for in vitro experiments to reveal the effects of NPs on these cells. The comparative study between Cu 0 AuNPs and L1@Cu 2+ AuNPs highlights that copper chelated in its +2 oxidation state in the NPs is more functional for biological application., Competing Interests: The authors declare no competing financial interest.

The use of phosphonate ligands to modify the nanoparticle (NPs) surface has attracted a strong interest in the last years for the design of highly functional hybrid materials. Here, we applied a methodology to synthesize bisphosphonates having functionalized PEG side chains with a specific length in order to design a novel class of hybrid nanomaterials composed by tetraphosphonate-complex-gold COOH-terminated PEG-coated NPs (Bis-PO-PEG-AuNPs). The synthetic approach consist in three steps: (1) Complexation between new phosphonate ligands (Bis PO) and tetrachloroauric acid (HAuCl 4 ) to form gold clusters; (2) adsorption of COOH-terminated PEG molecules (PEG) onto Bis PO-Au complex; (3) reduction of metal ions in that vicinity, growth of gold particles and colloidal stabilization. The obtained snow-shape-like hybrid nanoparticles, have been characterized by ultra-violet/visible, Raman spectroscopies, and electron microscopy imaging, involving their optical properties and photothermal activity in pancreatic adenocarcinoma cancer cells (PDAC)., (Copyright © 2017 Elsevier Inc. All rights reserved.)