Bionanocomposites: Integrating Biological Processes for Bioinspired Nanotechnologies

Beginning with a general overview of nanocomposites, Bionanocomposites: Integrating Biological Processes for Bio-inspired Nanotechnologies details the systems available in nature (nucleic acids, proteins, carbohydrates, lipids) that can be integrated within suitable inorganic matrices for specific applications.  Describing the relationship between architecture, hierarchy and function, this book aims at pointing out how bio-systems can be key components of nanocomposites. The text then reviews the design principles, structures, functions and applications of bionanocomposites. It also includes a section presenting related technical methods to help readers identify and understand the most widely used analytical tools such as mass spectrometry, calorimetry, and impedance spectroscopy, among others.

• Language: English
• Publisher: Wiley
• Release date: Jul 24, 2017
• ISBN: 9781118942239

Book preview

Table of Contents

Cover

Title Page

List of Contributors

1 What Are Bionanocomposites?

1.1 Introduction

1.2 A Molecular Perspective: Why Biological Macromolecules?

1.3 Challenges for Bionanocomposites

References

2 Molecular Architecture of Living Matter

2.1 Nucleic Acids

2.1.1 Introduction: A Bit of History

2.1.2 Definition and Structure

2.1.3 DNA and RNA Functions

2.1.4 Specific Secondary Structures

2.1.5 Stability

2.1.6 Conclusion

References

2.2 Lipids

2.2.1 Lipids Self‐Assembly

2.2.2 Structural Diversity of Lipids

2.2.3 Lipid Synthesis and Distribution

2.2.4 The Diversity of Lipid Functions

2.2.5 Lipidomics

References

2.3 Carbohydrates

2.3.1 Introduction

2.3.2 Monosaccharides

2.3.3 Oligosaccharides

2.3.4 Polysaccharides

References

2.4 Proteins: From Chemical Properties to CellularFunction: A Practical Review of Actin Dynamics

2.4.1 Introduction

2.4.2 Molecular Architecture of Proteins

2.4.3 Protein Folding

2.4.4 Interacting Proteins for Cellular Functions

2.4.5 Self‐Assembly and Auto‐Organization: Regulation of the Actin Cytoskeleton Assembly

2.4.6 Conclusion

References

3 Functional Biomolecular Engineering

3.1 Nucleic Acid Engineering

3.1.1 Introduction

3.1.2 How to Synthetically Produce Nucleic Acids?

3.1.3 Secondary Structures in Nanotechnologies

3.1.4 Conclusion

References

3.2 Protein Engineering

3.2.1 Synthesis of Polypeptides: Chemical or Biological Approach?

3.2.2 Proteins: From Natural to Artificial Sources

3.2.3 Proteins: A Large Repertoire of Functional Objects

References

4 The Composite Approach

4.1 Inorganic Nanoparticles

4.1.1 Introduction

4.1.2 Overview of Inorganic Nanoparticles

4.1.3 Synthesis of Inorganic Nanoparticles

4.1.4 Some Specific Properties of Inorganic Nanoparticles

4.1.5 Concluding Remarks

References

4.2 Hybrid Particles

4.2.1 General Considerations

4.2.2 Functionalization of Nanoparticle Surface

4.2.3 Linker‐Mediated Conjugation of Biomolecules to Nanoparticles

4.2.4 Conclusions

Acknowledgments

References

4.3 Biocomposites from Nanoparticles

4.3.1 General Considerations

4.3.2 One‐Dimensional Bionanocomposites

4.3.3 Two‐Dimensional Organization of Nanoparticles

4.3.4 Three‐Dimensional Organization of Particles

4.3.5 Conclusion and Perspectives

References

5 Applications

5.1 Optical Properties

5.1.1 Introduction

5.1.2 Interactions of Light with Matter

5.1.3 Optics at the Nanoscale

5.1.4 Optical Properties of Bionanocomposites

5.1.5 Conclusions

References

5.2 Magnetic Bionanocomposites

5.2.1 Introduction

5.2.2 Construction Strategies for Magnetic Biocomposites

5.2.3 Applications of Magnetic Biocomposites

5.2.4 Concluding Remarks and Future Trends

Acknowledgments

References

5.3 Mechanical Properties of Natural Biopolymer Nanocomposites

5.3.1 Introduction

5.3.2 Overview of Mechanical Properties of Polymer Nanocomposites and Their Measurement Methods

5.3.3 Solid Biopolymer Nanocomposites

5.3.4 Porous Biopolymer Nanocomposites

5.3.5 Biopolymer Nanocomposite Hydrogels

5.3.6 Conclusions

References

5.4 Bionanocomposite Materials for Biocatalytic Applications

5.4.1 Bionanocomposites and Biocatalysis

5.4.2 Form and Function in Bionanocomposite Materials for Biocatalysis

5.4.3 Applications

5.4.4 Conclusions and Perspectives

References

5.5 Nanocomposite Biomaterials

5.5.1 Introduction

5.5.2 Natural Nanocomposites

5.5.3 Synthetic Nanocomposites

5.5.4 Conclusions

Acknowledgments

References

6 A Combination of Characterization Techniques

6.1 Introductory Remarks

6.2 Chemical Analyses

6.3 Determining Size and Structure

6.4 Materials Properties

References

Index

End User License Agreement

List of Tables

Chapter 2.1

Table 2.1 Comparison of B‐form, A‐form, and Z‐form DNA structural parameters.

Chapter 2.2

Table 2.2 Lipid synthesis and composition of the different cell membranes [14].

Table 2.3 Synthetic view of the relationships between lipid diversity and membrane properties and functions.

Chapter 2.3

Table 2.4 List of most frequent mono‐ and disaccharides and definition of glycosyl‐containing compounds.

Chapter 2.4

Table 2.5 Name and properties of natural L‐amino acids.

Chapter 4.1

Table 4.1 Main inorganic nanoparticles and their specific properties.

Chapter 5.3

Table 5.1 A summary of tensile properties of some biopolymer–graphene nanocomposites, shown in percentage changes in contrast to the values for their polymer counterparts.

Chapter 06

Table 6.1 Radiation properties for scattering experiments.

List of Illustrations

Chapter 01

Figure 1.1 Examples for biological soft and hard matter: (a) trunk disc of an oak tree and (b) lower jawbone of a cow (mandible).

Figure 1.2 Structural hierarchy of soft tissue (oak wood) and hard tissue (bone): (a1) tissue, (a2) cells, (a3) cell walls, (a4) elementary fibrils, and (a5) biomolecules (cellulose and lignin); (b1) compact and spongy bone, (b2) osteons, (b3) collagen fibril, (b4) mineralized collagen triple helices, and (b5) collagen molecule and calcium phosphate nanocrystal.

Figure 1.3 Fundamental biological and dynamic processes that are absent in engineering materials. The development of the material during the lifetime of an organism is termed ontogenesis: (a) juvenile bone (woven bone) with unoriented collagen fibrils and (b) adult bone (lamellar bone) with highly oriented collagen fibrils. Morphogenesis is the development of form: (c) juvenile skull and (d) adult skull.

Chapter 2.1

Figure 2.1 Structures of the different nucleobases, sugars, and deoxyribonucleotides.

Figure 2.2 Double helical structure of B‐form DNA and nucleobase pair position in the helical structure in the antiparallel orientation.

Figure 2.3 Structure‐based cloverleaf models (left) and 3D L‐shaped structure (right) of A. aeolicus tRNASec.

Figure 2.4 Illustration of DNA replication.

Figure 2.5 Left: structure of a G‐quartet, with four guanines arranged around a central monovalent cation (M+). Right: schematic structure of a G‐quadruplex.

Figure 2.6 Typical melting curves of double‐stranded DNA.

Chapter 2.2

Figure 2.7 Schematic representation of the relationship between the packing parameter p and the self‐assembling properties of amphiphiles.

Figure 2.8 Representative structure for each of the eight lipid classes [12].

Figure 2.9 Representative structures for fatty acyls.

Figure 2.10 Representative structures for glycerolipids.

Figure 2.11 Representative structures for glycerophospholipids.

Figure 2.12 Representative structures for sphingolipids.

Figure 2.13 Representative structures for sterol and prenol lipids.

Figure 2.14 Representative structures for saccharolipids and polyketides.

Chapter 2.3

Figure 2.15 Schematic representation of sugar nomenclature. Both β‐D‐glucose and α‐L‐arabinose are shown in different types of representations that display their stereochemistry and conformations. From left to right: straight‐chain models, ball‐and‐stick models, conformational models, and Haworth projections. The ball‐and‐stick model demonstrates the convention whereby the last asymmetric carbon (marked with a white asterisk on the black carbon) is oriented with its hydrogen group to the rear. The size of the three asymmetric groups increases clockwise for D‐sugars or counterclockwise for L‐sugars. The conformational model distinguishes the relative axial and equatorial positions of the hydroxyl groups around the ring structure of pyranoses. D‐Glucose is the most stable of the hexoses because every hydroxyl group of the ring and the C‐6 primary alcohol group are in the equatorial position, which is energetically more favorable than other orientations. By convention, the α‐configuration of L‐arabinofuranose is in the up equatorial position.

Figure 2.16 Conformational representations of four common disaccharides. The nature of the individual glycoside units forming the disaccharide are indicated, as well as the type of glycosidic bond that links the two units. When the sugar units are linked through both reducing end, the relative conformation of both C‐1 carbons is indicated.

Figure 2.17 Schematic representation of some selected important human N‐glycosylation and O‐glycosylation patterns. The complexity of branching patterns observed for N‐glycosylation is illustrated in the upper row, while the lower panel shows the major determinants of type I blood group O‐glycosylation. The figure was prepared using the software GlycoWorkbench 2 [16].

Figure 2.18 Schematic representation describing the presence of cellulose fibrils in the cell wall of green plants. The scheme displays the different scales, starting at the macroscopic level of a leaf and ending at the molecular level, illustrating the hydrogen‐bonding network of intra‐ and interchain interactions stabilizing the crystalline state of cellulose microfibrils.

Figure 2.19 Different schematic representations to depict the structure, linkage, and branching of various polysaccharide chains. (a) Schematic representation of the chemical structure of xyloglucan; here the ideal sequence of the XXXG structure is represented; notably the unbranched backbone of this polysaccharide is composed of β‐1 → 4‐linked D‐glucose units. (b) Schematic representation of the chemical structure of the most simple xylan polysaccharide chain, composed of β‐1 → 4‐linked D‐xylose units, which are thus considered a derivate of the β‐1 → 4‐D‐glucose backbone, lacking the C‐6/O‐6 side chain. (c) Schematic representation all in one of pectin. The three major types of pectin domains, called homogalacturonan (HG), rhamnogalacturonan I (RG I), and rhamnogalacturonan II (RG II), are represented. It is important to note that the different structures shown here are intended only to illustrate some of the major domains found in most pectins rather than definitive structures. For details of the glycosyl units present in the different domains, see the description in the text section Pectins (d) Schematic representation of chitin: again the backbone of this polysaccharide is composed of β‐1 → 4‐linked D‐glucose units, the derivation from cellulose being the N‐acetylglucosamine modifications at C‐2. (e) Schematic representation of alginate; this polysaccharide chain is composed of mannuronic acid (M) units and their C‐5 epimer, guluronic acid (G); specific patterns of subsequent M or G units are the basis of physicochemical properties of various alginates.

Chapter 2.4

Figure 2.20 Protein structural properties. Primary, secondary, and tertiary structures are illustrated using ubiquitin, a small globular protein that includes many of the more complex traits of larger proteins. The ubiquitin fold is one of approximately 400 superfolds that are particularly frequently encountered in nature. (a) The primary structure of the human ubiquitin encoded by genetic information through the universal genetic code is represented. (b) The secondary structure scheme of ubiquitin (generated with PDB ID 1UBI and PDB sum) is characterized by the angles ϕ and ψ adopted by every amino acid in the primary structure, resulting mainly in α‐helices (helix) and β‐strands (arrows). They are characterized by the formation of hydrogen bonds with specific patterns. (c) The organization of the secondary structure elements in space through the establishment of long‐range contacts mainly between hydrophobic side chains corresponds to the tertiary structure. The structure in the left panel represents the overall tertiary structure of ubiquitin. The structure in the middle panel is another representation of the tertiary structure showing the van der Waals radii of the backbone and side chains of hydrophobic (darker, in the core) and polar (lighter at the surface) residues. Note the burial of hydrophobic residues in the protein core, while polar residues are exposed at the surface. The figure in the right panel reveals the hydrophobic residues because masking polar residues shown in the previous panel have been completely stripped from this image. The burial of hydrophobic residues in the center of the structure is a central characteristic of the native structure and folding reaction of globular proteins. (d and f) Two examples of quaternary structure described in the text: (d) the β‐galactosidase (PDB ID 4TTG) forms an obligate homotetramer. In this case, tetramerization is essential to obtain the native structure and enzymatic activity. (e) The green fluorescent protein (GFP; PDB ID 1GFL) was shown to form a weak dimer in solution. This dimerization was abrogated by the insertion of charged amino acids at the interface of monomers without affecting the tertiary structure and intrinsic fluorescence of GFP [13]. Tertiary and quaternary structure images in this figure were generated using the software Chimera.

Figure 2.21 Protein folding and refolding: two‐state or three‐state folding (i.e., with or without the formation of stable intermediates). (a) This panel shows a schematic representation of the folding pathway of proteins. Denatured proteins form or not intermediates that can be on‐ or off‐pathway (lighter lettering indicates that these steps are facultative) during the folding reaction that leads ultimately to the formation of native proteins. On‐pathway and off‐pathway intermediates are envisioned forming mostly native‐like and significant nonnative‐like contacts, respectively. As in other chemical reactions, the native state is obtained through a rate‐limiting step that consists in the formation of a transition state (TS). The scheme below the folding pathway represents schematically the denatured, intermediate, and native states where dark and light circles represent hydrophobic and polar residues. Note the absence of contacts in the denatured state, the formation of some contacts between hydrophobic residues in the intermediates and the formation of many long‐range hydrophobic contacts in the native state. (b) Native structure of chymotrypsin inhibitor 2 (CI2) a protein that folds through a two‐state mechanism (code PDB: 2CI2). (c) Native structure of barnase a protein that folds through a three‐state mechanism (code PDB 1A2P). Structure images represented in this figure were generated using the software Chimera.

Figure 2.22 Actin structure and dynamics. (a) Two X‐ray structures of the ATP–G‐actin monomer in the open (dark grey, 1hlu) or closed (light grey) state are superimposed. The ATP is in black. The transition between the open and closed states is defined by conformational changes, leading to a shortening of the distance between subdomains 2 and 4. (b) Recent advances in cryo‐EM techniques provided a high‐resolution model of the actin filaments in which the actin protomer is in the open state (PDB ID 3J8I) [95]. The barbed and pointed ends are indicated in the picture. (c) Scheme of the treadmilling of an actin filament and its regulation rate by ADF/cofilin and profilin. The depolymerization (bolded dashed arrow) and polymerization (dimed dashed arrow) reactions at pointed ends are numbered (1). The polymerization (bolded arrow) and depolymerization (dimed arrow) reactions at barbed ends are numbered (2). The presence of profilin (P, profilin path) prevents actin assembly at pointed ends to drives the polymerization flux exclusively at barbed ends. ADF increases by 25‐fold the rate of actin depolymerization (ADF path). In combination with profilin that accelerates by 100‐fold the rate of nucleotide exchange on depolymerized ADP–G‐actin, the assembly onto barbed ends is 125‐fold accelerated. (d) Acceleration of the treadmilling rate by ADF and capping proteins. The dependence of filament elongation rate (J) on the concentration of monomeric G‐actin [C] is represented. Css corresponds to the G‐actin concentration where the rates of actin polymerization at barbed ends (positive J values, solid lines) and depolymerization (negative J values, dotted lines) are equal. In the left panel, ADF, by increasing the rate of actin depolymerization (negative J values, ADF‐marked dotted lines), increases Css, (double arrow, shift of Css to a higher value), thus increasing actin polymerization rate. By capping the majority of barbed ends, capping proteins reduce the overall rate of barbed end elongation to almost zero (bolded solid line), establishing Css closed to . Thus, the rate of actin assembly on the remaining uncapped filaments is enhanced. The combination of ADF and capping proteins highly increases Css and the rate of elongation of the remaining free barbed ends.

Figure 2.23 In vitro biomimetic reconstitution of Arp2/3‐based or formin‐based motility. (a and b) Scheme of Arp2/3‐based or formin‐based motility assays, reconstituted with purified proteins (upper panels). At the steady state, ADF/cofilin, profilin in addition to capping proteins (CP) maintain a high treadmilling rate of F‐actin (growing filament). In this medium, beads coated with an Arp2/3 activator (NPF) or beads coated with formins nucleate a branched filaments network (a) or a network of parallel filaments (b), respectively. By polymerizing against the bead surface, this actin comet tail generates a force that propels beads with a constant rate. Lower panel: time‐lapse sequence of a beads coated with the ActA protein of Listeria that activates directly Arp2/3 (a, phase‐contrast), or the FH1‐FH2 domain of the mDia1 formin (b, Rhodamine‐labeled G‐actin) generating actin comet tails.

Chapter 3.1

Figure 3.1 Structures of natural and modified oligonucleotide backbones: (a) natural phosphodiester, (b) phosphorothioate, (c) morpholino, (d) locked nucleic acid (LNAs), (e) peptide nucleic acids (PNAs), and (f) hexitol nucleic acids (HNAs).

Figure 3.2 Basic principle of PCR, 1, denaturing step; 2, hybridization step; 3, extension step.

Figure 3.3 General SELEX procedure.

Figure 3.4 Autonomous DNA walker by Yin et al. The walker W consists of a DNA duplex with two single‐stranded feet. (a) Initially, the walker is attached to the track. The fuel hairpin molecules F can only be opened by occupied footholds (protruding sequence). (b) After hybridization of F, the left foot of the walker is detached from the track. (c) After hybridization of W with T, the walker has effectively taken one step to the right. W acts as a hybridization catalyst.

Figure 3.5 DNA origami and its applications: arbitrary 2D nanostructures, nano‐sized breadboards for the arraying of nanomaterials, and 3D nanostructures such as hollow polyhedrons.

Chapter 3.2

Figure 3.6 Overview of protein production. A typical procedure for expression of a recombinant protein in Escherichia coli. (a) The plasmid contains the protein coding sequence under the control of expression‐promoting sequences and is introduced into an expression E. coli strain (usually BL21 pLys S or M15) by chemical transformation or electroporation. (b) Cells were grown at 37°C in rich culture medium containing an antibiotic. Protein expression is induced by the addition of an inducer (often IPTG), and the cells are further incubated for 2–4 h for protein production. (c) The cells are harvested and resuspended in relevant buffer. They are submitted to freezing/thawing cycles and French press or sonication and/or treated with lysozyme and DNAse to break the cell wall and genomic DNA molecule. After centrifugation, a clarified sample of the soluble bacterial fraction containing the tagged protein is obtained. (d) The initial purification step is often performed on immobilized metal affinity chromatography (IMAC). For example, the His‐tagged proteins are purified from the supernatant using nickel‐affinity chromatography. A second purification step using size exclusion chromatography is often used as a final purification and conditioning step. (e) The production and purification procedure can be analyzed by electrophoresis on acrylamide gel (SDS‐PAGE) in denaturing conditions.

Figure 3.7 A generic bacterial expression vector. A standard E. coli expression vector is a circular DNA molecule and associates the following sequence elements: A sequence allowing replication in E coli (ori) and A selection marker is an antibiotic resistance gene to detect and maintain bacterial cells containing this DNA molecule.

Figure 3.8 Creation of molecular recognition by artificial evolution of protein. Phage display is commonly used to evolve new binding peptides or proteins, based on a principle that mimics a natural evolutionary process. The key concept is that predefined recognition properties do not need to be designed as they can be extracted from a highly diverse population of molecules and can then be very efficiently amplified by their genetic information. The source of diversity is a synthetic library (a), a very large collection of partially randomized sequences. The target molecule (b budding circle) is used as an affinity trap to retain the very few molecules of the library that, by chance, have a target‐complementary molecular structure (c). Most molecules of the library do not bind the target and are eliminated by washing step (d). The adapted binders, although initially at a non‐detectable concentration, are associated to a DNA sequence and can therefore be amplified very efficiently either by microorganism growth or by PCR (e). One round of selection and amplification is not usually sufficient to isolate the binders from the library, but the process of selection is iterative (f), and several selection rounds lead to specific target‐binding sequences (g).

Figure 3.9 Overview of protein bioconjugation strategies. In all these approaches, the protein of interest is represented as a sphere and synthetic probes used for labeling are represented as stars. (a) Direct labeling mainly involves side chain modification of proteins. Cysteine or lysine side chains can be covalently labeled following specific reactions with chemicals coupled to synthetic probes. (b) Orthogonal labeling involves chemical modification of unnatural amino acids incorporated in the protein of interest by genetic and metabolic engineering of bacterial strains. These labeling reactions are highly specific, involving chemical function absent in nature, as illustrated by examples of click chemistry and inverse electron‐demand Diels–Alder reactions. (c) Tag labeling involves the chemical modification of a small peptide tag‐added at an extremity of the protein sequence. A biotin moiety specifically added on the lysine residue of the AviTag™ by a biotin ligase (BirA) can further be used to interact with streptavidin. The hexahistidine tag is widely used, for example, for protein purification due to its high affinity for metal cations. (d) In self‐labeling systems, the protein of interest is produced in fusion with a labeling enzyme that can specifically interact and covalently bind its target/substrate. The target can be labeled with any desired probe. Following this principle, a variety of couple enzyme/target was discovered and engineered. (e) Specialized enzymes can catalyze covalent protein–protein assembly. As an example, Sortase A can ligate two proteins displaying, respectively, specific N‐ and C‐terminal sequences.

Chapter 4.1

Figure 4.1 Nanoparticle preparation via ball milling: (a) principle of ball milling and SEM images of graphite powders (b) before and (c) after milling.

Figure 4.2 Nucleation and growth of nanoparticles. (a) Nucleation occurs when the seed size exceeds a critical radius (rc) determined by the balance between bulk‐free energy and surface energy. (b) In La Mer’s model, if supersaturation is reached rapidly, multi nuclei are formed before the growth process starts.

Figure 4.3 Synthesis of CdSe quantum dots and the resulting TEM image.

Figure 4.4 The microemulsion route to metal nanoparticles.

Figure 4.5 TEM images of Fe nanoparticles obtained from Fe(CO)‐oleylamine precursors at various temperatures and times: (a) 30°C for 1 min, (b) 30°C for 60 min, (c) 30°C for 180 min, (d) 70°C for 60 min, (e) 100°C for 60 min, and (f) 130°C for 60 min. All scale bars represent 20 nm.

Figure 4.6 (a) TEM images of magnetite particles precipitated in aqueous medium. (b) Influence of the pH of precipitation on the mean particle size at fixed Fe(II)/Fe(III) ratio and ionic strength.

Figure 4.7 Stöber method to silica nanoparticles. (a) Mean particle size of silica particles (DLS number mean) as a function of water and ammonium hydroxide concentration for 0.28 M TEOS. (b) Example DLS distributions with increasing ammonium hydroxide concentrations for 0.28 M TEOS and 6 M H2O.

Figure 4.8 Shape control of ZnO nanocrystals through additives. TEM images and schematic crystal structure of particles obtained (a) in water, (b) with sodium dodecanoate, and (c) with dodecanoic acid.

Figure 4.9 The seed‐mediated method for gold nanorods preparation.

Figure 4.10 The quantum confinement effect in semiconductors leads to modification of the density and energy of electronic levels in the valence band (VB) and conduction band (CB), changing the gap between these two bands (Eg) and therefore the optical properties.

Figure 4.11 Surface plasmon resonance in metal nanoparticles: effect of (a) Au particle size r, (b) Au particle aspect ratio R, and (c) Au1–xAgx alloy composition on the surface plasmon resonance (SPR) band wavelength for different refractive index ns of the external medium.

Figure 4.12 Effect of nanoparticles (nanocharges) on the Young modulus E of polymer nanocomposites compared to that of the matrix alone Em for (a) PA6 and (b) PMMA matrix, illustrating high reinforcing effect at low concentration for multiwall carbon nanotubes (MWNT) and decreased modulus in the presence of alumina particles.

Chapter 4.2

Figure 4.13 Mechanism of formation of amide linkage through EDC activation of carboxyl group and catalytic effect of HOBt.

Figure 4.14 Functionalization of mesoporous silica nanoparticles (MSN) with TAT peptide through EDC chemistry.

Figure 4.15 Functionalization of MSN with ε‐poly‐L‐lysine through isocyanate chemistry.

Figure 4.16 Functionalization of superparamagnetic nanoparticles with lipase through glutaraldehyde and imine chemistry.

Figure 4.17 Functionalization of nanoparticles through the hydrazone linkage.

Figure 4.18 Linking the cyclic tripeptide c(RGDyK) to a surface of iron oxide nanoparticles through Mannich reaction.

Figure 4.19 Attachment of a carbohydrate molecule to the surface of nanoparticles through alkylation of amine‐functionalized surface with squarate moiety.

Figure 4.20 Conjugation of lipase to gold nanoparticles through click chemistry.

Figure 4.21 Surface functionalization of lanthanide nanoparticles through click chemistry, followed by formation of highly stable host–guest interactions between adamantane moiety and β‐cyclodextrin.

Figure 4.22 Functionalized MSN through coordination and His‐tag technique.

Chapter 4.3

Figure 4.23 (a) Schematic illustration of the multifunctional HSA‐iron oxide nanoparticles. The particles were incubated with dopamine, after which the particles became moderately hydrophilic and could be doped into HSA matrices before drug loading; (b) TEM of the HSA‐functionalized iron oxide nanoparticles in water; (c) representative images of mouse injected with HSA‐functionalized iron oxide nanoparticles, 18 h post injection: (i) in vivo NIRF, (ii) in vivo PET, and (iii) MRI images.

Figure 4.24 (a1) Schematic representation of the gated MSNs capped with the C3‐cleavage site containing peptide; (a2) TEM image of peptide‐functionalized MSNs showing the typical porosity associated to mesoporous matrix. (b1) Representation of the positively charged amino modified‐MSNs capped with a single‐stranded oligonucleotide. The delivery of the entrapped guest is selectively accomplished in the presence of the complementary oligonucleotide; (b2) TEM image of the loaded MSNs.

Figure 4.25 Operating principles of biomolecule–nanoparticle hybrid probes. (a) DNA‐based sensor: in the closed state, single‐stranded DNAs adopt a constrained conformation on gold particle resulting in fluorophore quenching by the nanoparticle. Upon target binding, the DNA conformation opens, the fluorophore is separated from the particle surface by about 10 nm because of the structural rigidity of the hybridized double‐stranded DNA, and fluorescence is restored. (b) β‐Galactosidase‐based sensor: (b1) electrostatic interactions with the particle inhibit the enzymatic activity; (b2) β‐galactosidase is displaced from the particle upon binding of the analytes, restoring its catalytic activity resulting in an amplified signal for spectroscopic detection.

Figure 4.26 (a) Thymine‐conjugated 10 nm gold nanocrystals annealed to approximately 50 nm polyadenine patterned lines on silicon. (b) SEM photo of the self‐assembly of gold nanoparticles onto six‐dot line nanopatterns. (c1) Schematic representation of DNA linkers on substrate, hybridizing with DNA‐modified gold nanocrystals, and (c2) SEM image of the resulting nanocrystal films.

Figure 4.27 (a) Schematic representation and TEM images of the molecular geometries obtained upon hybridization of DNA‐linked colloidal gold nanoparticles with a single complementary DNA oligonucleotide. In the schematic depictions, the solid lines represent double‐stranded DNA and the gray dotted circles the 2D plane. Scale bars (10 nm) are common for all images. (b) Schematic representation of DNA‐hybridization‐based assembly of single‐wall carbon nanotubes (SWNT) (1) with each other and (2) with gold nanoparticles (AuNPs). (3 and 4) Atomic force microscopy images of SWNT–AuNP structures.

Figure 4.28 (a) Schematic representation and (b) photograph of the gold nanoparticles (AuNPs) colorimetric strategy for thrombin detection in the presence and absence of a target protein (from left to right: 83 nM thrombin, 83 nM BSA, and water).

Figure 4.29 (a) Collagen adsorption and fibrillogenesis from sulfonate‐modified silica particles, as shown by TEM. (b) Magnetic nanoparticles assembled with ferritin via electrostatic interactions and corresponding TEM images.

Chapter 5.1

Figure 5.1 The four fundamental interactions between light and matter from which optical phenomena are derived. (a) Absorption; (b) emission; (c) reflection/refraction; (d) diffuse reflection/scattering.

Figure 5.2 Basic principles in photonic materials: (a) Reflection of a specific EM wave from a band gap photonic crystal and (b) possible periodic arrangements of a photonic material.

Figure 5.3 Principles in nanooptical science and technology.

Figure 5.4 Examples of photomodulating compounds: Azobenzenes, spiropyrans, and diarylethenes.

Figure 5.5 Quantum dots as a marker for GlyR localization in neurons: (a) QD‐GlyRs (dark dots), detected over the somatodendritic compartment identified by microtubule‐associated protein‐2. Arrows mark clusters of quantum dot‐GlyRs located on dendrites, (b) relation of QD‐GlyRs (dark dots) with inhibitory synaptic boutons labeled for vesicular inhibitory amino acid transporter, scale bar 10 µm.

Figure 5.6 Laser types: (a) Conventional laser with a dye as gain medium, (b) distributed feedback (DFB) diode laser with a grating delimiting one side of the gain medium, and (c) random laser with scattering particles distributed in the gain medium.

Figure 5.7 Random lasing in bone: (a) Emission spectrum of the dye solution (Rhodamine 800 in ethanol) without the bone specimen, (b) emission spectra of random lasers from the bone tissue (thickness = 200 µm) infiltrated with Rhodamine 800 at different positions, (c) emission spectrum of random lasers obtained from a thick bone specimen (thickness = 5 mm) infused with Rhodamine 800 in DMSO, and (d) dependence of the output laser intensity on the pump power. Inset: scanning electron micrograph (SEM) image of the bone tissue. The scale bar is 1 µm.

Figure 5.8 Assembly scheme of a bionanocomposite organic light‐emitting diode (OLED) component; ITO = indium tin oxide.

Figure 5.9 Architectures of bionanocomposite materials from butterflies with multifunctional properties: (a) Forewing of Euploea mulciber covered with CdS nanoparticles and (b) wings from Papilio nephelus nanoparticulate precipitates of core–shell CdS/Au/TiO2 on the wing architecture.

Chapter 5.2

Figure 5.10 Representative hysteresis loops for a magnetic sample that is (a) ferromagnetic and (b) superparamagnetic; Ms, Mr, and Hc represent the saturation magnetization, remnant magnetization, and coercivity, respectively.

Figure 5.11 Schematic representation of the preparation of magnetic alginate particle gels by using blending method.

Figure 5.12 Schematic illustration of the preparation of magnetic PGA–CS microcapsules.

Figure 5.13 The strategies of synthesis of 3‐APTES‐modified chitosan–Fe3O4 nanoparticles and enzyme immobilization.

Figure 5.14 Schematic representation of the magnetic separation process based on the use of magnetic composites, as illustrated for the depollution of water [19], the removal of dye [20], and the separation of protein from crude samples [21].

Figure 5.15 Preparation process of the ion‐imprinted magnetic chitosan resin cross‐linked with glutaraldehyde.

Figure 5.16 Biotechnological applications for polysaccharide‐coated magnetic nanoparticles.

Figure 5.17 Magnetic nanoparticles applied in cancer disease: diagnosis (MRI) and therapy (hyperthermia, drug delivery, and controlled release).

Figure 5.18 T2‐weighted MR images for five slices of the kidneys: (a) upper, (b) upper intermediate, (c) middle, (d) lower intermediate, and (e) lower. (a)–(e) were taken as a series of successive slices. The slice thickness was 2.8 mm and the slice gap was 0.4 mm. Microspheres were injected only into the left kidney. The right kidney served as a non‐injected control.

Figure 5.19 Uses of magnetic particles in tissue engineering. (a) Different cell types are separately labeled using magnetite cationic liposomes and sequentially seeded onto an ultralow attachment plate under which a magnet is placed. This leads to the generation of 3D multilayered heterotypic cell sheets by magnetic force‐based tissue engineering (Mag‐TE). Removal of the magnet allows the recovery of the construct for use. (b) Tubular structures can be generated by folding preformed cell layers, obtained as shown in panel (a), around rod‐shaped magnetic models. Such tubular constructs are recovered after removal of the magnet.

Figure 5.20 Phase‐contrast microscope images illustrating the growth in the magnetic scaffolds of NOM cells that have migrated from the cells–MCs aggregates treated with: (a) bFGF‐conjugated nanoparticles and (b) free bFGF ×5, 18 days after the cultivation.

Figure 5.21 SEM images of new bone tissue growing inside and around magnetic scaffolds. (a) MAG‐A. (b) A detail of MAG‐A. (c) MAG‐B at 4 weeks. Scaffold delimited by dashed line; arrows show mineralization. (b′) and (d) show osteocyte lacunae (indicated by asterisks) in the new bone grown inside MAG‐A and MAG‐B, respectively. Scale bars: a and c, 1.0 mm; b, 300 µm; d, 100 µm.

Figure 5.22 Simplified cross‐sectional scheme of the use of magnetically labeled streptavidin to detect the location of prehybridized biotinylated DNA on chip. A posthybridization magnetoresistive DNA chip detection strategy. Step 1: Probe DNA immobilized over on‐chip magnetoresistive sensors are hybridized with biotinylated target DNA. Step 2: Magnetically labeled streptavidin is used to detect the hybridized DNA by binding to the biotinylated hybridized target DNA. The magnetic fringe field of the labels is detected by the sensors.

Chapter 5.3

Figure 5.23 (a) Atomic force micrograph of graphene oxide single layers and (b) scanning electron micrograph of montmorillonite clay layers.

Figure 5.24 Relative tensile properties of (a) gelatin–graphene oxide and (b) chitosan–graphene oxide nanocomposites showing that the addition of no more than 2 wt.% graphene oxide improves the tensile strength, modulus, elongation at break, and energy at break of the polymer.

Figure 5.25 Transmission electron micrographs of paraffin–clay nanocomposites (a) before and (b) after stretching showing orientation of clay layers toward testing direction and polyamide 6‐clay nanocomposites (c) and (d) after stretching showing delamination of clay layers from the intercalated tactoids to form voids.

Figure 5.26 (a and b) Young’s modulus versus volume fraction of graphene for (a) chitosan‐reduced graphene oxide nanocomposite films and (b) gelatin–graphene oxide nanocomposite films, showing that the theoretical values predicted using the Halpin–Tsai or Mori–Tanaka model are lower than the experimental data when nominal volume fractions are used. When effective volume fractions of the nanofiller are considered with a kx of 0.22, both theoretical models predict the experimental data reasonably well. (c) Scheme illustrating that a layer of polymer molecules with a thickness of xRg is adsorbed onto nanofiller surface, contributing to the effective volume fraction of the reinforcing phase.

Figure 5.27 Scanning electron micrographs of (a) a chitosan–bacterial cellulose nanocomposite foam with interconnected open cells and (b) a gelatin–sepiolite nanocomposite foam with closed cells.

Figure 5.28 Experimental and theoretical results of relative modulus versus relative density for (a) gelatin–sepiolite and (b) chitosan–bacterial cellulose nanocomposite foams showing the theoretical values predicted with the normalized Gibson–Ashby model for open cells follow the experimental data reasonably well. In Mills and Zhu models, C1 = 0.0598, n = 1.066, or C1 = 0.0807, n = 1.155, while in Roberts and Garboczi model, C1 = 0.76, n = 1.7 [113, 124, 128].

Figure 5.29 Dynamic shear storage moduli G′ (solid symbols) and loss moduli G″ (hollow symbols) of gelatin–graphene oxide nanocomposite hydrogels with different material ratios indicating that the modulus can be modulated by varying the material composition: (a) with a fixed graphene oxide content of 10 mg ml−1 and (b) with a fixed gelatin content of 10 mg ml−1.

Chapter 5.4

Figure 5.30 The elaboration of bionanocomposite materials for biocatalytic applications relies on a vast set of possible components, ranging from inorganic solids (c–h) to biopolymers (i–m) and biocatalysts (n–p).

Figure 5.31 The mechanical properties of different biopolymer‐coated culture substrates play a key role in the morphology of corneal epithelium cells. The different cell culture media were obtained by coating PDMS substrates with different elastic modulus (ranging from 5 to 1720 kPa) with different extracellular matrix (ECM) proteins, such as fibronectin (FN), collagen type I (COLI), laminin (LAM), collagen type IV (COL4), or LAM and COL4.

Figure 5.32 Sporopollenin obtained from Lycopodium clavatum forms capsules (a), which can be activated (b), and covered with silica gel in order to entrap enzymes (c).

Figure 5.33 The elaboration of SiO2@CoFe2O4@CNTs platform for the immobilization of enzymes enhances the enzyme’s thermal and chemical stability and renders the nanomaterial fully recoverable by the application of an external electric field.

Figure 5.34 The cascade reaction pathway of glucose oxidase and horseradish peroxidase supported in layered self‐assembled calcium niobate nanosheets allows for the radical polymerization of PEGMA and subsequent exfoliation of the layered inorganic solid.

Figure 5.35 The selectivity toward cholesterol of the cholesterol oxidase/chitosan/layered double hydroxide/Pt (darker left columns) biosensor was greatly enhanced by the co‐encapsulation of horseradish peroxidase (right columns).

Figure 5.36 Different composite chitosan (CHT) and carbon‐based electrodes (CGE) were tested. The electrode containing both hemoglobin and calcium carbonate nanoparticles (Hb‐CHT/nano‐CaCO3/CGE) (a) shows much more defined redox peaks than the one containing no calcium carbonate (b). The electrode containing no hemoglobin (CHT/nano‐CaCO3/CGE) (c) and the CGE control (d) show no distinct redox peaks at all.

Figure 5.37 Degrading efficiency toward atrazine of Pseudomonas sp. ADP is greatly improved upon immobilization within Mg–Al layered double hydroxide.

Figure 5.38 SEM images and the corresponding bio‐electron transfer schematic diagrams of MWCNT@rGO1:2 hybrid (a and b), rGO (c and d), and MWCNT (e and f). Arrows in (a) are indications of MWCNTs.

Chapter 5.5

Figure 5.39 Scanning electron microscopy images of (from top to bottom) chitosan, keratin, and collagen hydrogels.

Figure 5.40 Transmission electron microscopy images of (from top to bottom) chitosan nanowhiskers, graphene nanosheets, and silica nanoparticles.

Figure 5.41 Schematic representation of nanocomposite obtention from polymeric materials and nanofillers.

Figure 5.42 Schematic model illustrating the formation of regenerated cellulose‐based ZnO nanocomposite films via one‐step coagulation.

Figure 5.43 Scanning electron microscopy images of bacterial cellulose (BC) (a: surface morphology and c: cross‐section morphology) and BC/PEG composite scaffolds (b: surface morphology and d: cross‐section morphology).

Figure 5.44 Schematic illustration of the role of HA in the SA/HA‐DS nanocomposite beads.

Figure 5.45 Rat calvarium regeneration after 12 weeks of implantation of GEMOSIL–CS scaffold. (a) Thin tissue and fragmentation was bridged by connective tissue in the defect site. (b) New bone formation occurred within the gap and around GEMOSIL–CS scaffold from the calvarial edge. Pores were formed as a sign of degradation of the HGCS. Steven’s blue staining counterstained with Van Gieson; bar represents 500 µm, NC natural carvarium, D defect site. Arrows separate natural calvarium and defect site.

Figure 5.46 Scanning electron microscopy images of the rMSCs grown on fibroin surface of the Hap/SF—5% scaffold (a: scale bar 30 µm and b: scale bar 10 µm). The cells migrated into the pores and spread within the scaffold. MTT assay (c) and LDH activity (d) show that all the samples did not significantly change the proliferation rate of the cells and were not cytotoxic.

Figure 5.47 Synthesis of photocross‐linked PEG–silica nanocomposite hydrogels. (a) Hydrogel solutions were prepared by mixing silica (x = 0, 1, 2.5, 5, 10 wt%) and PEG diacrylate (5%) in an initiator solution. The solutions were injected in a mold and cross‐linked with UV light. (b) PEG hydrogels are transparent, but the addition of silica nanospheres decreases the optical transmittance. (c) Compositions of nanocomposite hydrogels.

Figure 5.48 Scanning electron microscopy images of scaffold morphology: PLGA (a and b); PU (c and d); PLGA/PU blend (e and f).

Chapter 06

Figure 6.1 Schematic illustration of the scope