Synthesis of core-shell magnetic nanoparticles for biomedical applications / Ana Arizaga Páez

224 Pages·2013·7.68 MB·English

by  Ana Arizaga Páez

2013 77
Ana Arizaga Páez
Synthesis of core-shell
magnetic nanoparticles for
biomedical applications
Departamento
Física de la Materia Condensada
Director/es
Millán Escolano, Ángel
Palacio Parada, Fernando
Tesis Doctoral
Autor
Director/es
UNIVERSIDAD DE ZARAGOZA
Repositorio de la Universidad de Zaragoza – Zaguan http://zaguan.unizar.es
Departamento
Director/es
Tesis Doctoral
SYNTHESIS OF CORE-SHELL
MAGNETIC NANOPARTICLES FOR
BIOMEDICAL APPLICATIONS
Autor
Ana Arizaga Páez
Director/es
Millán Escolano, Ángel
Palacio Parada, Fernando
UNIVERSIDAD DE ZARAGOZA
Física de la Materia Condensada
2013
Repositorio de la Universidad de Zaragoza – Zaguan http://zaguan.unizar.es
Departamento
Director/es
Tesis Doctoral
Autor
Director/es
UNIVERSIDAD DE ZARAGOZA
Repositorio de la Universidad de Zaragoza – Zaguan http://zaguan.unizar.es
Synthesis of Core-Shell Magnetic
Nanoparticles for Biomedical Applications

Synthesis of Core-Shell Magnetic Nanoparticles for
Biomedical Applications

Ana Arizaga Páez
A Jose Luís y Ainhoa
Index

Preface.....................................................................................................1
1 Introduction and goals...........................................................................3
1.1 Advantages of MNPs in biomedical uses..........................................3
1.1.1 Magnetic resonance imaging (MRI)........................................6
1.1.2 Magnetic hyperthermia............................................................7
1.1.3 Biosensors................................................................................8
1.1.4 Drug delivery...........................................................................8
1.1.5 Targeting..................................................................................9
1.2 Magnetic properties of nanoparticles...............................................10
1.2.1 Superparamagnetism..............................................................12
1.2.2 Magnetic relaxation................................................................14
1.2.3 Specific absorption rate (SAR)..............................................15
1.2.4 Surface effects........................................................................16
1.3 Core-Shell structures of MNPs used in medicine............................16
1.3.1 Materials for the core.............................................................18
1.3.1.1 Iron oxides: An introduction........................................19
1.3.1.2 Synthesis of iron oxide MNPs......................................21
1.3.1.3 Strategies for the control of size in nanoparticles........25
1.3.2 Materials for the shell.............................................................26
1.3.2.1 Organic coatings...........................................................27
1.3.2.2 Inorganic coatings........................................................32
viii Index
1.4 Purpose of the thesis and goals........................................................35
1.4.1 Ferrofluids for biomedical applications.................................35
1.4.2 Superparamagnetic beads for a biosensor..............................36
1.4.3 MNPs encapsulated in a polymer for drug delivery...............37
1.5 Bibliography....................................................................................38

2 Experimental and methods..................................................................49
2.1 Introduction......................................................................................49
2.2 Experimental....................................................................................49
2.2.1 A survey of methods for the production of ferrofluids
in organic media.....................................................................50
2.2.2 Synthesis of IOMNPs in organic solvents by thermal
decomposition of Fe(CO) .....................................................53
5
2.2.2.1 Procedure for the synthesis of organic nanoparticle
suspensions............................................................................55
2.2.3 Ferrofluids in aqueous media.................................................57
2.2.4 Procedure for the synthesis of aqueous MNPs suspensions...61
2.3 Methods...........................................................................................61
2.3.1 Chemical analysis..................................................................61
2.3.1.1 Titration........................................................................61
2.3.1.2 Thermogravimetric analysis.........................................63
2.3.1.3 Gel permeation chromatography..................................63
2.3.1.4 1H-NMR.......................................................................64
2.3.2 Structural characterization.....................................................65
2.3.2.1 Fourier transform infrared spectroscopy (FTIR)..........65
2.3.2.2 X-ray diffraction (XRD)...............................................66
2.3.2.3 Dynamic light scattering (DLS)...................................67
2.3.2.4 Transmission electron microscopy (TEM) ..................68
2.3.3 Magnetic characterization......................................................69
2.3.3.1 Magnetic characterization SQUID...............................69
2.3.3.2 SAR..............................................................................70
Index ix
2.4 Characteristics of the organic MNPs suspensions...........................70
2.5 Magnetic properties of the organic MNPs suspensions...................76
2.6 Magnetothermic properties of the organic MNPs suspensions........78
2.7 Characteristics of aqueous prepared ferrofluids...............................82
2.8 Bibliography....................................................................................85

3 Core-Shell ferrofluids for biomedical applications...........................87
3.1 Introduction......................................................................................87
3.1.1 Transferring nanoparticles from organic to aqueous media...89
3.1.2 Use of silanes for particle coating and redispersion in water.91
3.1.3 Dispersing hydrophobic nanoparticles in water by ligand
exchange.................................................................................92
3.1.4 Our approach for the production of silica coated aqueous
dispersions..............................................................................94
3.2 Experimental....................................................................................96
3.2.1 Synthesis................................................................................96
3.2.2 Physical and chemical characterization..................................97
3.3 Results..............................................................................................98
3.3.1 Use of short chain organosilanes with iron coordinating
group......................................................................................98
3.3.1.1 Diethylphosphatoethyltriethoxysilane..........................98
3.3.1.2 N-(3-triethoxysilylpropyl)-4,5-dihydroimidazole......103
3.3.2 Use of long chain organosilanes with iron coordinating
groups...................................................................................107
3.3.2.1 Magnetic properties....................................................110
3.4 Conclusions....................................................................................113
3.5 Bibliography..................................................................................115

4 Superparamagnetic beads for a biosensor.......................................123
4.1 Introduction....................................................................................123
4.2 Synthesis and characterization of superparamagnetic nanobeads..127