"A nanoparticle or ultrafine particle is usually defined as a particle of matter that is between 1 and 100 nanometres (nm) in diameter."
Size, shape, surface area, and unique properties of nanoparticles.
Introduction to Nanoparticles: This topic covers basic concepts related to nanoparticles, including their dimensions, types, and properties.
Synthesis of Nanoparticles: In this topic, different methods for the synthesis of nanoparticles are discussed, including physical, chemical, and biological methods.
Characterization Techniques: Various analytical and spectroscopic techniques are used to study the properties of nanoparticles.
Surface Chemistry of Nanoparticles: Surface chemistry plays a crucial role in determining the behavior of nanoparticles in different environments.
Properties of Nanoparticles: In this topic, the physical, chemical, and biological properties of nanoparticles are discussed, including their unique characteristics such as high surface area, quantum confinement, and surface plasmon resonance.
Applications of Nanoparticles: Nanoparticles have numerous applications in various fields, including medicine, electronics, and energy.
Toxicity and Environmental Impact of Nanoparticles: As nanoparticles have a high surface area-to-volume ratio, they have the potential to cause environmental and health risks.
Assembly and Self-Assembly of Nanoparticles: Nanoparticles can be assembled into complex structures and patterns using various techniques such as templating, lithography, and self-assembly.
Nanoparticle-based Sensors: Nanoparticles can be used as sensors for various applications, including detection of biomolecules, gases, and contaminants.
Nanoparticle-based Drug Delivery Systems: Nanoparticles have gained considerable attention as drug delivery systems due to their ability to deliver drugs to specific targets and improve drug efficacy.
Gold nanoparticles: A popular choice due to their biocompatibility and optical properties. They are often used in biomedical imaging and photothermal therapy.
Silver nanoparticles: Known for their antimicrobial properties and used in wound healing products and as a water treatment agent.
Iron oxide nanoparticles: Magnetic nanoparticles used in magnetic resonance imaging (MRI) and targeted drug delivery.
Quantum dots: Semiconducting nanoparticles with unique optical and electronic properties. They are used in solar cells, LED displays, and bioimaging.
Carbon nanotubes: Cylindrical structures made of carbon atoms with high mechanical strength and electrical conductivity. They have potential applications in electronics, energy storage, and drug delivery.
Liposomes: Spherical nanoparticles made of lipids used in drug delivery and gene therapy.
Dendrimers: Complex and highly branched structures used in drug delivery, imaging, and sensing.
"The term is sometimes used for larger particles, up to 500 nm, or fibers and tubes that are less than 100 nm in only two directions."
"Nanoparticles are usually distinguished from microparticles (1-1000 µm), 'fine particles' (sized between 100 and 2500 nm), and 'coarse particles' (ranging from 2500 to 10,000 nm), because their smaller size drives very different physical or chemical properties."
"Being more subject to the Brownian motion, they usually do not sediment, like colloidal particles that conversely are usually understood to range from 1 to 1000 nm."
"Being much smaller than the wavelengths of visible light (400-700 nm), nanoparticles cannot be seen with ordinary optical microscopes, requiring the use of electron microscopes or microscopes with laser."
"For the same reason, dispersions of nanoparticles in transparent media can be transparent, whereas suspensions of larger particles usually scatter some or all visible light incident on them."
"They are an important component of atmospheric pollution and key ingredients in many industrialized products such as paints, plastics, metals, ceramics, and magnetic products. The production of nanoparticles with specific properties is a branch of nanotechnology."
"Since the typical diameter of an atom is between 0.15 and 0.6 nm, a large fraction of the nanoparticle's material lies within a few atomic diameters of its surface. Therefore, the properties of that surface layer may dominate over those of the bulk material."
"Non-spherical nanoparticles exhibit shape-dependent and size-dependent (both chemical and physical) properties. Non-spherical geometries of nanoprisms give rise to high effective cross-sections and deeper colors of the colloidal solutions."
"The possibility of shifting the resonance wavelengths by tuning the particle geometry allows using them in the fields of molecular labeling, biomolecular assays, trace metal detection, or nanotechnical applications."
"Colloidal particles... are usually understood to range from 1 to 1000 nm."
"Anisotropic nanoparticles display a specific absorption behavior and stochastic particle orientation under unpolarized light, showing a distinct resonance mode for each excitable axis."
"Since the typical diameter of an atom is between 0.15 and 0.6 nm..."
"Nanoparticles occur widely in nature and are objects of study in many sciences such as chemistry, physics, geology, and biology."
"...requiring the use of electron microscopes or microscopes with laser."
"...so that separation from liquids requires special nanofiltration techniques."
"In general, the small size of nanoparticles leads to a lower concentration of point defects compared to their bulk counterparts."
"Non-spherical nanoparticles of gold (Au), silver (Ag), and platinum (Pt) due to their fascinating optical properties are finding diverse applications."
"...usually understood to range from 1 to 1000 nm."
"The production of nanoparticles with specific properties is a branch of nanotechnology."