Nanostructured, electroactive and bioapplicable materials

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crystalline phases. Silicate species deposit between surfactant “rods” and then condense to form the inorganic network. The interaction of the surfactant and silicate species mediates the hexagonal ordering. After removing the surfactant templates from the as- synthesized sample, materials exhibit mesoporosity with pore size of 2-10 nm. In general, the overall LCT mechanism is directed by two features. One is the dynamics of surfactant molecules to form assemblies, micelle, and ultimately crystalline structure, which functions as template. The other is the ability of the inorganic oxide to undergo hydrolysis and polycondensation reactions to form network around the organic template. Since the discovery of M41S family, the surfactant template hydrothermal pathway has been extensively studied and expanded to sol-gel process. 32,33 A wide variety of surfactant molecules with different sizes, shapes, functionalities and charges have been subsequently demonstrated to be able to effectively function as pore structure directing agents. These surfactant molecules can be classified based on their head group chemistry and charge as follows. − Cationic surfactants: the hydrophilic group carries a positive charge, e.g., tetraalkylammonium salts 34 (CnH2n+1)(CH3)3NX, n = 6, 8, 9, 10, 12, 14, 16,18, 20, 22; X= OH, Cl, Br, HSO4; and (CnH2n+1)(C2H5)3N, n = 12, 14, 16, 18). − Anionic surfactants: the hydrophilic group carries a negative charge, e.g., sulfates 35 (CnH2n+1OSO3 (n =12, 14, 16, 18), sulfonates 36 (C16H33SO3H and C12H25C6H4SO3Na), and phosphates (C12H25OPO3H2, C14H29OPO3K). 11
− Neutral surfactants: the hydrophilic group is not charged, e.g., primary amines 37 (CnH2n+1NH2) and poly(ethylene oxides) 38,39 (PEO). It is necessary to point out that in neutral surfactant templating systems where strong electrostatic interactions are absent, LCT mechanism may not be suitable to describe the mesophase formation. Instead, neutral surfactants have much stronger tendency to form aggregations in solution. 40 Those aggregations of surfactant molecules and the hydrogen bonding interactions may play an important role in directing the mesophase formation in the case of neutral surfactant templates. The surfactant templated approach has also been extended from silicates and aluminosilicates 41-44 to a wide range of metal oxides. With this method, a variety of mesoporous inorganic oxide frameworks, some of which may have important technological applications, have been achieved, including: titanium oxide, 45,46 zirconium oxide, 47,48 vanadium oxide, 49 tungsten oxide, 50 and so forth. Porosity control during the surfactant templated sol-gel synthesis has been considerably studied. The pore geometry is controlled primarily by the template concentration, charge of the surfactant and the processing conditions. 32 For example, mesoporous materials prepared with charged surfactants usually exhibit ordered hexagonal porous structure, while the materials obtained with neutral surfactants sometimes lack a long range ordered channel arrangement and exhibit both complementary textural and framework-confined mesoporosity. 37 Pore size, recently being expanded up to 30 nm, 51 can be controlled by the size of the surfactant, addition of 12
Page 1: Nanostructured, Electroactive and B
Page 4 and 5: Dedications This dissertation is de
Page 6 and 7: School of Biomedical Engineering, S
Page 8 and 9: 2.2. Experimental .................
Page 10 and 11: 5.2.2. Treatment of Substrate Surfa
Page 12 and 13: 8.2. Electroactive, Bioapplicable M
Page 14 and 15: List of Tables Table 2-1. Compositi
Page 16 and 17: Figure 2-9. BJH pore size distribut
Page 18 and 19: xvi pattern of gold nanoparticles i
Page 20 and 21: xviii PANI under culturing conditio
Page 22 and 23: Figure B-8. Cyclic voltammogram (Pt
Page 24: The resultant polyaniline-collagen
Page 27 and 28: Chapter 2 presents a study focused
Page 29 and 30: Chapter 7 is focused on the synthes
Page 31 and 32: surfactant templated method was ext
Page 33 and 34: The porous structure of the silica
Page 35: Before early 1990s, with a pore or
Page 39 and 40: The mechanism of nonsurfactant temp
Page 41 and 42: zero in a pore. Structural informat
Page 43 and 44: 1.5.1. Gas Sorption Measurement As
Page 45 and 46: which is usually associated with ca
Page 47 and 48: 16. Iler, R. K. The Chemistry of Si
Page 49 and 50: 52. Sayari, A.; Danumah, C.; Moudra
Page 51 and 52: Figure 1-1. Three structure types p
Page 53 and 54: Figure 1-3. IUPAC classification of
Page 55 and 56: Chapter 2. Mesoporous Sol-Gel Mater
Page 57 and 58: well formed below the isoelectric p
Page 59 and 60: 2.1.2. Nonsurfactant Templates and
Page 61 and 62: since controllable partial removal
Page 63 and 64: were ground manually into fine powd
Page 65 and 66: volatile sol-gel reaction byproduct
Page 67 and 68: After the thermal treatment at 150
Page 69 and 70: oiling point of benzoin (i.e., 194
Page 71 and 72: interconnected pores or channels wi
Page 73 and 74: 6. Huo, Q.; Magargolese, D. I.; Cie
Page 75 and 76: Table 2-1. Composition and pore par
Page 77 and 78: Weight (%) 100 80 60 40 20 0 0 100
Page 79 and 80: Weight (%) 100 90 80 70 60 0 100 20
Page 81 and 82: Weight (%) 100 90 80 70 60 50 40 0
Page 83 and 84: Figure 2-7. Representative IR spect
Page 85 and 86: dV/dD Pore Volume (cm 3 g -1 Å -1
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dv/dD, Pore Volume (cm 3 g -1 Å -1
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Net Pore Volume (cm 3 g -1 ) 0.6 0.
Page 91 and 92:
Chapter 3. Synthesis of Mesoporous
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preparation conditions. In general,
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cubic, as well as vesicular structu
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3.2 Experimental The synthesis appr
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3.2.3. Synthesis of Mesoporous Sphe
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fructose is incorporated into the s
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mainly attributed to the monolayer-
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with nonsurfactant templates at dif
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3.4. Conclusions and Remarks In the
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11. Matijević, E.; Gheradi, P. Tra
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41. Polarz, S.; Smarsly, B.; Bronst
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(a) (b) Figure 3-1. Typical SEM ima
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Volume Adsorbed (cm 3 g -1 , STP) 3
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Figure 3-5. Representative TEM imag
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(a) (b) Figure 3-7. Typical SEM ima
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Chapter 4. Synthesis of Mesoporous
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nm, and the reaction reaches the hi
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microemulsion. 39 Martino et al. re
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the colloidal gold sol was combined
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holders with adhesive carbon tape.
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trapped in the gold-silica matrix,
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108 The Barrett-Joyner-Halenda (BJH
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indicative of a well-defined crysta
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(i.e., 2-50 nm). Combining both hig
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19. Hayashi, T.; Tanaka, K.; Haruta
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53. Qi, L.; Ma, J.; Cheng, H.; Zhao
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Figure 4-1. Representative X-ray en
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Pore Volume (cm 3 g -1 A -1 ) 0.06
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(a) (b) 122 Figure 4-5. (a) Represe
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Absorbance Wavelength (nm) Figure 4
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5.1.1. Organic-Inorganic Nanocompos
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128 We are also interested in the p
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mica and graphite, the top layer wa
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mode. Scanning electron microscopy
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Waal’s forces), the agglomeration
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136 A single glass transition tempe
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5.5. Acknowledgments 138 I want to
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30. Dimitrov, A. S.; Nagayama, K. L
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(a) (b) 142 Figure 5-2. Representat
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144 Figure 5-4. Representative AFM
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Figure 5-6. Representative IR spect
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(a) (b) Figure 5-8. Representative
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the possibility of utilizing conduc
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iocompatibility and water solubilit
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emeraldine salt, the unique conduct
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acid (HCl, 37.3%, Fisher), hydrogen
Page 183 and 184:
the surface of polymer coated cultu
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acidic acid aqueous solution showed
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oxidant, indicating the formation o
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complex was synthesized by pre-alig
Page 191 and 192:
8. Epstein, A. J. Springer Ser. Mat
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45. Liu, J.-M.; Yang, S. Chem. Comm
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Figure 6-1. Schematics of biologica
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172 Figure 6-3. UV-Vis absorption s
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Figure 6-5. FT-IR spectra of (a) co
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176 Figure 6-7. UV-Vis absorption s
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(a) (b) 178 Figure 6-9. Comparison
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prepared and purified as substitute
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greatest advantages of organic mate
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een explored as a direct and effect
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if we could fine-tune the carrier t
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NMR (250 MHz, DCCl3) δ (ppm): 8.95
Page 215 and 216:
7.2.4. Instrumentation and Characte
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The absence of the proton from the
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194 The absorbance at 600 nm is the
Page 221 and 222:
L3Al dissociated to free ligand (L)
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198 State and Integrated Circuit Te
Page 225 and 226:
34. Stossel, M.; Staudigel, J.; Ste
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Table 7-1. The UV absorbance at 600
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Figure 7-2. Schematic cross-section
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Figure 7-4. NMR Spectra of ligand 1
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Figure 7-6. FT-IR spectra of (a) li
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Figure 7-8. During air oxidation: 1
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[A] 1.2E-04 1.0E-04 8.0E-05 6.0E-05
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Figure 7-12. Mass spectrum of alumi
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Chapter 8. Concluding Remarks 216 T
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218 In contrast to the conventional
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properties of gold nanoparticles ma
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222 In an effort to obtain new elec
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as sensor units, the biodegradable
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polyanhydrides, 4 polyorthoesters,
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substitution reaction, several hund
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polyphosphazenes. Obtained material
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polyphosphazene network. Studies in
Page 259 and 260:
matrix is readily formed due to the
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236 The delivery system can be made
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phosphazene main chains. Further in
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9. Allcock, H. R. Adv. Mater. 1994,
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Figure A-1. Repeating unit in polyp
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Figure A-3. Applications of materia
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Figure A-5. Preparation of poly(N-i
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B.3. Acknowledgments 248 I am grate
Page 275 and 276:
Figure B-2. Cyclic voltammogram (Hg
Page 277 and 278:
Figure B-4. Cyclic voltammogram (Pt
Page 279 and 280:
Figure B-6. Cyclic voltammogram (Hg
Page 281 and 282:
Figure B-8. Cyclic voltammogram (Pt
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