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1. Introduction to organic nanomaterials

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Into the nanoscale

1. Introduction

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1 nm - 100 nm

1 nm = 10 -3 m = 10 -9 m

1 = 0.1 nm = 10 -10 m

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On the role of nanochemistry

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Organic nanochemistry

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1. Introduction

Organic surface chemistry

Organic nanoparticles (materials)

Supramolecular chemistry

Organic biomaterials

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Why nano? Size effects on material properties (1/2)

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1. IntroductionExample: Nanoparticles

Size dependence of melting point Size dependence of surface area

Size dependence of band gap

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Size effects on material properties (2/2)

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1. Introduction

Quite generally, many of these size-specific changes in material properties apply to organic nanomaterials as they

do for inorganic nanomaterials

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Some definitions (1/3)

Nanocrystal

A solid particle which is a single crystal in the nanometer range

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1. Introduction

Cryst. Eng. Comm., DOI: 10.1039/c2ce26000j

Nanoparticle

A solid particle in the 1-100 nm range that could be noncrystalline, an aggregate of crystallites or a single crystallite

Nanoshell

A type of spherical nanoparticle consisting of a dielectric core which is covered by a thin metallic (or organic) shell

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Some definitions (2/3)

Micelle

A spherical aggregate of lipid molecules dispersed in

a liquid colloid

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1. Introduction

Liposome

An artificially-prepared spherical vesicle composed of

a lipid bilayer

Vesicle

A spherical supramolecular assembly of lipid

molecules

Colloid

A stable liquid phase containing particles in the 1-

1000 nm range; a colloid particle is one suche 1-1000

nm particle.

Cluster

A collection of units (atoms or reactive molecules) of

up to 50 units (number varies here) Dendrimer

Repetitively branched (macro)molecule

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Some definitions (3/3)

The four categories of nanomaterials:

Zero-dimensional:length, width and height are confined to a single point (example: nano

dots)

One-dimensional:Object/system has only one parameter, i.e. either length, width orheight (example: surface coatings)

Two-dimensional:System has length and width (example: nanotubes, nanowires)

Three-dimensional:System is a 3D object (example: nanoparticle)

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1. Introduction

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How can we produce nanostructures mechanically?

Atom-by-atom assembly: Moving atoms into place one at at time using AFM, STM, etc. Chisel away atoms: Like a sculptor, chisel out material from a surface until the desired structure

emerges

Etching, irradiation, and other mechanical nanofabrication procedures

Top down approach - Nanotechnology

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1. Introduction

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How can we produce nanostructures chemically? (1/4)

by building macromolecules with covalent linkages

Bottom up approach - Nanochemistry

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1. Introduction

Basic FGIs

Condensation chemistry

Cycloaddition chemistry

Cross-coupling chemistry

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How can we produce nanostructures chemically? (2/4)

Bottom up approach - Nanochemistry

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1. Introduction

Ref

by building structures on surfaces

Self-assembly processes on metal surfaces

or

Metal-catalyzed coupling reactions on the surface

or

Combination of both processes

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How can we produce nanostructures chemically? (3/4)

Bottom up approach - Nanochemistry

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1. Introduction

by self assembly processes in solution

Supramolecular interactions:

Electrostatic (ion-ion, dipole-dipole)

Van-der-Waals forces

-Stacking

Hydrogen bonding

Hydrophobic & hydrophilic effects

J. Am. Chem. Soc., 128 (2006): 15098-15099.

Nanoplasctics fibre

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How can we produce nanostructures chemically? (4/4)

Bottom up approach - Nanochemistry

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1. Introduction

or by using polymer chemistry

Nanoplasctics fibre

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Top down vs. bottom up approach

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1. Introduction

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Applications of (organic) nanomaterials? There are plenty

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1. Introduction

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Nanotechnology and the environment

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1. Introduction

Bio-uptake

sorption/desorption

aggregationdeposition

naturally occurring particles organic compounds/macromolecules/contaminants

nanoparticles

transport3A2

3A3

3A1

Example: nanoparticles in aqueous environments

Particle mediated transport of organic contaminants may occur (surface adsorption, aggregation)

Biouptake may lead to enrichment in the food chain (drugs, pesticides, etc.)

Deposition may lead to long-term contamination of habitat

Factors influencingadsorption:- hydrophobicity of

particle- particle charged

- Moleculesamphiphilic orcharged

- Macromoleculesadsorb most strongly

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Little is known about the fate of nanomaterialsin the biosphere

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1. Introduction

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Relevant biological properties of nanoparticles

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1. Introduction

Biouptake through

- Endocytosis

- Membrane penetration

- Transmembrane channels

Resistance to degradation (persistence)

Generation of active oxygen species in tissues Inflammatory responses

Binding to proteins leading to conformational changes

(Associated auto immune disorders)

Interaction with nucleic acids

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Nanotoxicology a potential issue

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1. Introduction

Nano industry product types worldwide 2009

CosmeticsPersonal care

Food supplementsFood packagingAgrochemicals

Veterinary medicines

PaintsCoatingsCatalysts

LubricantsTextiles

Medical care

Water decontaminationElectronics

Fuel cellsPaper manufactureWeapons industry

other

60%

10%

10%

10%10%