Seite - 8 - in Cancer Nanotheranostics - What Have We Learnd So Far?

REVIEWARTICLE published:15July2014 doi: 10.3389/fchem.2014.00048 Revisiting30yearsofbiofunctionalizationandsurface chemistryof inorganicnanoparticles fornanomedicine JoãoConde1*†, JorgeT.Dias2†,ValeriaGrazú2*,MariaMoros2,PedroV.Baptista3 and JesusM.de laFuente2,4,5 1 Harvard-MITDivision forHealthSciencesandTechnology, Institute forMedicalEngineeringandScience,Massachusetts InstituteofTechnology, Cambridge,MA,USA 2NanotherapyandNanodiagnosticsGroup, InstitutodeNanocienciadeAragon,UniversidaddeZaragoza,Zaragoza,Spain 3 CIGMH,DepartamentodeCiênciasdaVida,FaculdadedeCiênciaseTecnologia,UniversidadeNovadeLisboa,Caparica,Portugal 4 FundacionARAID,Zaragoza,Spain 5 KeyLaboratory forThinFilmandMicrofabricationTechnologyof theMinistryofEducation,DepartmentofBio-NanoScienceandEngineering, InstituteofNanoBiomedicineandEngineering,Research InstituteofTranslationMedicine,Shanghai JiaoTongUniversity,Shanghai,China Editedby: Jean-Michel Lavoie,Universitéde Sherbrooke,Canada Reviewedby: VictorSansSangorrin,Universityof Glasgow,UK LeonieRouleau,Universitéde Sherbrooke,Canada *Correspondence: JoãoConde,Harvard-MITDivision forHealthSciencesandTechnology, Institute forMedicalEngineering andScience,Massachusetts InstituteofTechnology,45Carleton Street,E25-438,Cambridge,MA 02139,USA e-mail: jdconde@mit.edu; ValeriaGrazú,Nanotherapyand NanodiagnosticsGroup, Institutode NanocienciadeAragon,Universidad deZaragoza,CampusRioEbro, Edifício ID,MarianoEsquillor s/n, 50018Zaragoza,Spain e-mail: vgrazu@unizar.es †Theseauthorshavecontributed equally to thiswork. In the last 30 yearswehave assisted to amassive advance of nanomaterials inmaterial science. Nanomaterials and structures, in addition to their small size, have properties that differ from those of larger bulk materials, making them ideal for a host of novel applications. The spread of nanotechnology in the last years has been due to the improvement of synthesis and characterization methods on the nanoscale, a field rich in new physical phenomena and synthetic opportunities. In fact, the development of functional nanoparticles has progressed exponentially over the past two decades. This work aims to extensively review 30 years of different strategies of surfacemodification and functionalization of noble metal (gold) nanoparticles, magnetic nanocrystals and semiconductor nanoparticles, such as quantumdots. The aim of this review is not only to provide in-depth insights into the different biofunctionalization and characterization methods, but also to give an overview of possibilities and limitations of the available nanoparticles. Keywords:biofunctionalization, chemistrysurface,goldnanoparticles,magneticnanoparticles,quantumdots INTRODUCTION Every object with at least one characteristic dimension between 1and100nmcanbedefinedas “nanomaterial.”The importance of nanomaterials (e.g. nanoparticles, NPs) for science and tech- nology has highly increased in the last years (Surendiran et al., 2009).Whendealingwith sucha small structure, the size-related properties, the shape and inter-particle distance to the core, the charge, thedielectricpropertiesof theconjugatedsystem(includ- ing refractive index and polarizability), the dielectric medium surrounding theparticle (solvent) and the compositionmoieties are extremely important andmay sturdily influence the physi- calandchemicalcharacteristicsof thenanomaterials.Thismeans that these distinct properties, such as quantum confinement in semiconductornanocrystalsor surfaceplasmonresonance(SPR) insomemetalNPs,mayinfluencephysicalandchemicalbehavior ofnanomaterials (Bellucci,2009;Doriaetal., 2012). The unbelievable development of nanotechnology in the last 30 years has allowed the release of new and efficient synthetic routes toward the production and functionalization of differ- ent NPs, composed of a variety of materials including noble metals [e.g. gold and silver (Conde et al., 2012c; Doria et al., 2012;Dreadenetal.,2012)],semiconductors[e.g.CdSeandCdTe (Murrayetal., 1993),TiO2 (Sudhagaretal., 2012), InP(Xuetal., 2006)],magnetic compounds (Pankhurst et al., 2003), and their combinations, suchascore–shell (Caoetal., 2001)andalloyNPs (Doriaetal., 2010). The unique characteristics of these NPs, such as high surface-to-volume ratio or size-dependent optical andmagnetic properties,aredrasticallydifferent fromthoseof theirbulkmate- rials and hold pledge in the clinical field (Kim, 2007; Heath and Davis, 2008). Technological advances in nanoparticle syn- thesis/functionalization are producing significant advances in molecular detection and imaging, target and multifunctional therapeutics and in prevention/control of diseases. Through the development of new imaging agents, novel multifunctional targeted devices capable of overcoming biological barriers for www.frontiersin.org July2014 |Volume2 |Article48 |8