293
Table 11.1 The most widely studied ENPs, their properties and applications
Class of ENPs
Diameter
a,b
(nm)
Applications
I. Carbonaceous compounds
1. Fullerenes
0.72
Sorption of organic compounds, removal of organometallic
compounds, etc.
2. Carbon nanotubes (CNTs)
Single-walled
nanotubes
(SWNTs)
1–2
(diameter)
For sorption of metals and rare earth metals, water purification
systems, electronics, computers, plastics, catalysts, electrodes,
supercapacitor, implants, adhesives, composites, sensors,
automotive industries, etc.
5–30 μm
(length)
Multiwalled
nanotubes
(MWNTs)
<8 (OD)
2–5 (ID)
10–30 μm
(length)
II. Metals and metal oxides
1. Titanium oxide
(TiO 2 )
5
Skin care products, sunscreen lotions, solar cells, paints,
bioremediation, etc.
2. Zinc oxide
(ZnO)
20
Skin care products
III. Semiconductor devices
1. Quantum dots
(QDs)
1–10
Medical imaging, therapeutics, solar cells, photonics and
telecommunications, etc.
IV. Zero-valent metals
1. Zero-valent
iron
20–50
Bioremediation; detoxification of organochlorine pesticides,
polychlorinated biphenyls, herbicides, etc.
2. Silver NPs
10
Wound dressings, air filters, toothpastes, baby products, etc.
3. Gold NPs
3–20
Catalyst in flexible conducting inks or films, vector in tumor
therapy, etc.
V. Nanopolymers
1. Dendrimers
1–10
Macrocapsules, nanolatex, colored glasses, chemical sensors,
modified electrodes, DNA transfecting agents, drug delivery,
tumor treatment
2. Liposome
50–100
Phospholipid vesicles, passive and active delivery of gene,
protein, peptide, etc.
3. Polymeric
micelles
10–100
Long circulatory, target-specific active and passive drug
delivery, etc.
4. Polymeric
nanoparticles
10–1000
Controlled and sustained active and passive drug/bioactives
delivery
a
The diameter given is that of a single nanoparticle and often the smallest size commercially
available
b
Nanoparticles in solution may form aggregates resulting in larger particles
OD represents outside diameter and ID means inside diameter
11 Environmental Impact and Econanotoxicity of Engineered Nanomaterials
Table 11.1 The most widely studied ENPs, their properties and applications
Class of ENPs
Diameter
a,b
(nm)
Applications
I. Carbonaceous compounds
1. Fullerenes
0.72
Sorption of organic compounds, removal of organometallic
compounds, etc.
2. Carbon nanotubes (CNTs)
Single-walled
nanotubes
(SWNTs)
1–2
(diameter)
For sorption of metals and rare earth metals, water purification
systems, electronics, computers, plastics, catalysts, electrodes,
supercapacitor, implants, adhesives, composites, sensors,
automotive industries, etc.
5–30 μm
(length)
Multiwalled
nanotubes
(MWNTs)
<8 (OD)
2–5 (ID)
10–30 μm
(length)
II. Metals and metal oxides
1. Titanium oxide
(TiO 2 )
5
Skin care products, sunscreen lotions, solar cells, paints,
bioremediation, etc.
2. Zinc oxide
(ZnO)
20
Skin care products
III. Semiconductor devices
1. Quantum dots
(QDs)
1–10
Medical imaging, therapeutics, solar cells, photonics and
telecommunications, etc.
IV. Zero-valent metals
1. Zero-valent
iron
20–50
Bioremediation; detoxification of organochlorine pesticides,
polychlorinated biphenyls, herbicides, etc.
2. Silver NPs
10
Wound dressings, air filters, toothpastes, baby products, etc.
3. Gold NPs
3–20
Catalyst in flexible conducting inks or films, vector in tumor
therapy, etc.
V. Nanopolymers
1. Dendrimers
1–10
Macrocapsules, nanolatex, colored glasses, chemical sensors,
modified electrodes, DNA transfecting agents, drug delivery,
tumor treatment
2. Liposome
50–100
Phospholipid vesicles, passive and active delivery of gene,
protein, peptide, etc.
3. Polymeric
micelles
10–100
Long circulatory, target-specific active and passive drug
delivery, etc.
4. Polymeric
nanoparticles
10–1000
Controlled and sustained active and passive drug/bioactives
delivery
a
The diameter given is that of a single nanoparticle and often the smallest size commercially
available
b
Nanoparticles in solution may form aggregates resulting in larger particles
OD represents outside diameter and ID means inside diameter
11 Environmental Impact and Econanotoxicity of Engineered Nanomaterials