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Gene therapy based on small interfering RNA (siRNA) has emerged as an exciting new therapeutic approach. In this work, incorporation of PEI into poly(d,l-lactide-co-glycolide)-poly(ethylene glycol) (PLGA-b-PEG) particles has been shown to be quite effective in the development of corresponding gene delivery systems, and encapsulation of magnetic nanoparticles as an MRI contrast agent, resulted in unique theranostic nanoparticles.

A series of novel functional carbazole (Cbz)-based carboxylated monomers were synthesized and characterized. A Clauson-Kaas procedure, a deprotection step, amide coupling, and hydrolysis were utilized as key chemical reactions towards the multistep synthesis of monomers in good to excellent isolated yields. The design strategy was further extended to complex carbazole-COOH monomers incorporated arylazo groups as photoreactive moieties. In addition, photoreactive hybrid carbazole (Cbz)-pyrrole (Pyr)-based carboxylated monomers, comprising a pyrrole core linking a carbazole and a photoreactive phenylazide or benzophenone moiety through an amide spacer in the molecular structure, were also synthesized. The latter can be utilized for surface modification of polymeric films in their monomeric form or as polymeric microparticles (MPs).

Aim: Targeted biocompatible nanoplatforms presenting multiple therapeutic functions have great potential for the treatment of cancer. Materials & methods: Multifunctional nanocomposites formed by polymeric nanoparticles (PNPs) containing two cytotoxic agents – the drug alisertib and silver nanoparticles – were synthesized. These PNPs have been conjugated with a chlorotoxin, an active targeting 36-amino acid-long peptide that specifically binds to MMP‑2, a receptor overexpressed by brain cancer cells. Results: The individual and synergistic activity of these two cytotoxic agents against glioblastoma multiforme was tested both in vitro and in vivo. The induced cytotoxicity in a human glioblastoma–astrocytoma epithelial‑like cell line (U87MG) was studied in vitro through a trypan blue exclusion test after 48 and 72 h of exposure. Subsequently, the PNPs’ biodistribution in healthy animals and their effect on tumor reduction in tumor‑bearing mice were studied using PNPs radiolabeled with 99mTc. Conclusion: Tumor reduction was achieved in vivo when using silver/alisertib@PNPs–chlorotoxin., JRC.I.4-Nanobiosciences

Four types of innovative benzophenone (BPh)- or aryl azide (ArAz)-containing photoreactive polycarbazole (polyCbz)- based microparticles (MPs) were prepared using an oxidative liquid phase polymerization system. Their photochemical reactivity was evaluated by their reaction with highly inert poly(2-chloro- paraxylelene) (Parylene C) films. Possible mechanisms for the photochemical reaction of those MPs with Parylene Cw ere discussed. The highly photoreactive BPh was found to react more inside the particle causing internal cross-linking of MP polyCbz chains, fusion between adjoining particles and deformation of their spherical structure. In contrast, the less reactive but more selective ArAz-containing MPs were found to react much more with Parylene C. The strong reactivity of such photoreactive MPs toward Parylene C films emphasizes a general method for the functionalization of stable nonfunctional polymeric coatings. This paves the way to simple and solvent-free functionalization of nonfunctional coatings and materials by light. V C 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 000: 000-000, 2011

Two possible mechanisms for the reaction of four halogenated (metha)acrylate-based molecules with Parylene (poly (paraxylylene)) during its chemical vapor deposition were proposed. The chemical reactivity of acrylate double bond with the paraxylylene biradical was calculated for all four (metha)a- crylate-based molecules. These calculations allowed the evalua- tion of the energetically favorable mechanism and indeed a direct correlation was found between both predicted and exper- imental reactivities. Next, the reactivity of the (metha)acrylate- modified Parylene films was evaluated through their reaction with different amines. The obtained amidated Parylene films were characterized with X-ray photoelectron spectroscopy, Kaiser test for primary amines, and fluorescence microscopy. The strong reactivity of (metha)acrylate-modified Parylene films toward nucleophilic substitution emphasizes a general method for the functionalization of self-supported Parylene films grown on the reacting solutions using the novel solid on liquid deposi- tion process. This paves the way to the development of multi- functional materials in a one-step process resulting from the deposition Parylene over liquid patterns. V C 2011 Wiley Periodi- cals, Inc. J Polym Sci Part A: Polym Chem 49: 2952-2958, 2011

none 11 no Recently the use of phosphorescent heavy-metal complexes in bioimaging techniques has been a promising research field and has been attracted increasing interest. Among these, phosphorescent iridium(III) complexes have shown many photophysical characteristics that made them promising candidates for fluorescence probes. In this study an innovative copolymer consisting of cholesterol, a natural component of biological membranes, and the well-known biocompatible Polyethylene (PEG), has been synthesized. Cholesterol–PEG amphiphilic copolymer has been used to formnovel nanocarriers characterized by the incorporation and/or linkage of the phosphorescent iridium(III) derivatives through covalent or non-covalent interactions. Finally the nanocarrier's surface has been functionalized with the peptide chlorotoxin (Cltx), a targeting agent selective for glioblastoma cells (U87MG). The so obtained targeted water soluble nanocarrier has been tested for in vitro imaging on the glioblastoma cell line and has shown no toxic effect on cells. Naddaka, Maria; Locatelli, Erica; Colecchia, David; Sambri, Letizia; Monaco, Ilaria; Baschieri, Andrea; Sasdelli, Federica; Chiariello, Mario; Matteucci, Elia; Zani, Paolo; Comes Franchini, Mauro Naddaka, Maria; Locatelli, Erica; Colecchia, David; Sambri, Letizia; Monaco, Ilaria; Baschieri, Andrea; Sasdelli, Federica; Chiariello, Mario; Matteucci, Elia; Zani, Paolo; Comes Franchini, Mauro

A straightforward oxidative liquid phase polymerization (LPP) method has been successfully developed for the fabrication of spherical functional (polyCOOH) polycarbazole-based microparticles from corresponding carbazole-containing monomers. The influence of the chemical structure of starting carbazole monomers on the LPP-based microparticle formation has been deeply examined using scanning electron microscopy (SEM).

Erica Locatelli,1 Larraitz Gil,2 Liron Limor Israel,3 Lorena Passoni,4,5 Maria Naddaka,1 Andrea Pucci,1 Torsten Reese,6 Vanessa Gomez-Vallejo,2 Paolo Milani,5,7 Michela Matteoli,4,8 Jordi Llop,2 Jean Paul Lellouche,3 Mauro Comes Franchini11Department of Industrial Chemistry “Toso Montanari”. University of Bologna, Italy; 2Radiochemistry Department, Molecular Imaging Unit, CIC biomaGUNE, San Sebastián, Guipúzcoa, Spain; 3Department of Chemistry, Nanomaterials Research Centre, Institute of Nanotechnology and Advanced Materials, Bar-Ilan University, Ramat-Gan, Israel; 4Department of Medical Biotechnology and Translational Medicine, University of Milano, Italy; 5Fondazione Filarete, Milano, Italy; 6Imaging Department, Molecular Imaging Unit, CIC biomaGUNE, San Sebastián, Guipúzcoa, Spain; 7CIMAINA and Department of Physics, University of Milano, Italy; 8Humanitas Clinical and Research Center, Rozzano, ItalyAbstract: A novel nanocarrier system was designed and developed with key components uniquely structured at the nanoscale for early cancer diagnosis and treatment. In order to perform magnetic resonance imaging, hydrophilic superparamagnetic maghemite nanoparticles (NPs) were synthesized and coated with a lipophilic organic ligand. Next, they were entrapped into polymeric NPs made of biodegradable poly(lactic-co-glycolic acid) linked to polyethylene glycol. In addition, resulting NPs have been conjugated on their surface with a 2,2'-(7-(4-((2-aminoethyl)amino)-1-carboxy-4-oxobutyl)-1,4,7-triazonane-1,4-diyl)diacetic acid ligand for subsequent 68Ga incorporation. A cell-based cytotoxicity assay has been employed to verify the in vitro cell viability of human pancreatic cancer cells exposed to this nanosystem. Finally, in vivo positron emission tomography-computerized tomography biodistribution studies in healthy animals were performed.Keywords: maghemite nanoparticles, organic coating, polymeric nanoparticles, magnetic resonance imaging, radiolabeling, positron emission tomography

This paper reports a simple method for the controllable synthesis of highly effective SiO2@Pt supported catalysts. Hybrid photoreactive silica nanoparticles (NPs) modified with benzophenone (SiO2@BPh) were used as the supporting phase while Pt NPs were used as the catalyst. Monodisperse Pt NPs were homogeneously deposited on the supporting phase with full control of metal loading (from 2.15 to 34.60 wt%) via direct photoreduction of the PtCl62− metal precursor. The catalytic activities of our supported catalysts were evaluated by the reduction reaction of 4-nitrophenol by sodium borohydride. These catalytic activities were found to be much higher than those of unsupported Pt NPs reported in the literature and commercial Pt/C supported catalyst. The facile synthetic method established in this study should largely contribute to the further development of various highly effective supported catalysts.

Monodisperse, colloidal silica nanoparticles (NPs) are being widely investigated due to a variety of applications in various fields of chemistry. Many works utilize incorporation of various functional groups to silica NPs for their further modifications. However, at present no benzophenone (BPh) or phenyl azide (PA) containing silica NPs exist. Upon UV irradiation BPh and PA form highly reactive species that react with any organic material. Here we present a convenient method for the preparation of novel hybrid photoreactive silica NPs (denoted as SiO2@photoreactive group) prepared by co-condensation of photoreactive organosilanes and tetraethyl orthosilicate (TEOS) to obtain SiO2@PA and SiO2@BPh NPs. The reactivity of these two types of silica NPs is compared to that of perfluorinated phenyl azide (PFPA) based SiO2 NPs. The reactivity evaluation is carried out by the reaction of the three types of SiO2 NPs with highly inert poly(2-chloro-paraxylelene) films. It is found that, in contrast to what is stated in the literature, PA is much more reactive than PFPA, when dealing with solid state photochemical reactions. Next, photoreactive silica NPs on polymer films are used as an intermediate functional phase for a second modification step using silane-based chemistry. A successful incorporation of amine functionality onto silica NPs is achieved by their reaction with 3-aminopropyltriethoxysilane (APTES) and is verified by fluorescence microscopy. This strategy provides a general and versatile route to efficient functionalization of silica by light.