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Nanoprobe (device)
A nanoprobe is an optical device developed by tapering an optical fiber to a tip measuring 100 nm = 1000 angstroms wide. Nanoprobes can be used in bioimaging to provide improved contrast and spatial resolution of cells and tissues. Types of nanoprobes used for bioimaging include fluorescence, chemiluminescence, and photoacoustic imaging. Introduction to Raman Scattering When light interacts with matter, a phenomenon known as Raman scattering occurs, which provides important information about the vibrational frequencies of the sample. This phenomenon happens when a sample's molecules interact with incident light, scattering it. Every material has a different Raman spectrum because of the information the scattered light has about the vibrational modes of the constituent molecules. Raman scattering: The reflection of light from a laser-lit object. A very thin coating of silver nanoparticles helps to enhance the Raman scattering effect of the light. (The phenomenon of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nanoprobing
Nanoprobing is method of extracting device Current–voltage characteristic, electrical parameters through the use of nanoscale tungsten wires, used primarily in the semiconductor industry. The characterization of individual devices is instrumental to engineers and integrated circuit designers during initial product development and debug. It is commonly utilized in device failure analysis laboratories to aid with yield enhancement, quality and reliability issues and customer returns. Commercially available nanoprobing systems are integrated into either a vacuum-based scanning electron microscope (SEM) or atomic force microscope (AFM). Nanoprobing systems that are based on AFM technology are referred to as Atomic Force nanoProbers (AFP). Principles and operation AFM based nanoprobers, enable up to eight probe tips to be scanned to generate high resolution AFM topography images, as well as Conductive AFM, Scanning Capacitance, and Electrostatic Force Microscopy images. Conductive A ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
APS - Nanoprobe
APS or Aps or aps or similar may refer to: Businesses and organizations Businesses and public bodies *Algeria Press Service, a news agency *Arizona Public Service, an electric power company *Australian Protective Service, an Australian Commonwealth law enforcement agency *Australian Public Service, the federal civil service of the Commonwealth of Australia *ASTRA Platform Services, now SES Platform Services Education * Abbottabad Public School, in Pakistan * Adarsh Public School, in India * Alamogordo Public Schools, in New Mexico, U.S. * Albuquerque Public Schools, in New Mexico, U.S. * Allendale Public Schools, in Michigan, U.S. * Arlington Public Schools, in Virginia, U.S. * Associated Public Schools of Victoria, in Australia * Atlanta Public Schools, in Georgia, U.S. * Aurora Public Schools ** Aurora Public Schools (Colorado), in Colorado, U.S. ** East Aurora Public School District 131, in Illinois, U.S. ** West Aurora Public School District 129, in Illinois, U.S. * Ind ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Photoacoustic Imaging
Photoacoustic imaging or optoacoustic imaging is a biomedical imaging modality based on the photoacoustic effect. Non-ionizing laser pulses are delivered into biological tissues and part of the energy will be absorbed and converted into heat, leading to transient thermoelastic expansion and thus wideband (i.e., megahertz-order bandwidth) ultrasonic emission. The generated ultrasonic waves are detected by ultrasonic transducers and then analyzed to produce images. It is known that optical absorption is closely associated with physiological properties, such as hemoglobin concentration and oxygen saturation. As a result, the magnitude of the ultrasonic emission (i.e. photoacoustic signal), which is proportional to the local energy deposition, reveals physiologically specific optical absorption contrast. 2D or 3D images of the targeted areas can then be formed. Biomedical imaging The optical absorption in biological tissues can be due to endogenous molecules such as hemoglobin or ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Theranostics
Theranostics, also known as theragnostics, is a technique commonly used in Personalized medicine, personalised medicine. For example in nuclear medicine, one Radiopharmacology, radioactive drug is used to identify (Diagnosis, diagnose) and a second radioactive drug is used to treat (therapy) Cancerous tumor, cancerous tumors. In other words, theranostics combines radionuclide imaging and radiation therapy which targets specific Biological pathway, biological pathways. Technologies used for theranostic imaging include radiotracers, contrast agents, positron emission tomography, and magnetic resonance imaging. It has been used to treat thyroid cancer and Neuroblastoma, neuroblastomas. The term "theranostic" is a portmanteau of two words, ''thera''peutic and diag''nostic'', thus referring to a combination of diagnosis and treatment that also allows for continuing medical assessment of a patient. The first known use of the term is attributed to John Funkhouser, a consultant for the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Microdialysis
Microdialysis is a minimally-invasive sampling technique that is used for continuous measurement of free, unbound analyte concentrations in the extracellular fluid of virtually any tissue. Analytes may include endogenous molecules (e.g. neurotransmitter, hormones, glucose, etc.) to assess their biochemical functions in the body, or exogenous compounds (e.g. pharmaceuticals) to determine their distribution within the body. The microdialysis technique requires the insertion of a small microdialysis catheter (also referred to as microdialysis probe) into the tissue of interest. The microdialysis probe is designed to mimic a blood capillary and consists of a shaft with a semipermeable hollow fiber membrane at its tip, which is connected to inlet and outlet tubing. The probe is continuously perfused with an aqueous solution (perfusate) that closely resembles the (ionic) composition of the surrounding tissue fluid at a low flow rate of approximately 0.1-5μL/min. Once inserted into t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nanoparticles
A nanoparticle or ultrafine particle is a particle of matter 1 to 100 nanometres (nm) in diameter. 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. At the lowest range, metal particles smaller than 1 nm are usually called atom clusters instead. Nanoparticles are 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, like colloidal properties and ultrafast optical effects or electric properties. Being more subject to the Brownian motion, they usually do not sediment, like colloid, 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 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Surface Enhanced Raman Spectroscopy
Surface-enhanced Raman spectroscopy or surface-enhanced Raman scattering (SERS) is a surface-sensitive technique that enhances Raman scattering by molecules adsorbed on rough metal surfaces or by nanostructures such as plasmonic-magnetic silica nanotubes. The enhancement factor can be as much as 1010 to 1011, which means the technique may detect single molecules. History SERS from pyridine adsorbed on electrochemically roughened silver was first observed by Martin Fleischmann, Patrick J. Hendra and A. James McQuillan at the Department of Chemistry at the University of Southampton, UK in 1973. This initial publication has been cited over 6000 times. The 40th Anniversary of the first observation of the SERS effect has been marked by the Royal Society of Chemistry by the award of a National Chemical Landmark plaque to the University of Southampton. In 1977, two groups independently noted that the concentration of scattering species could not account for the enhanced signal and e ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Silver
Silver is a chemical element; it has Symbol (chemistry), symbol Ag () and atomic number 47. A soft, whitish-gray, lustrous transition metal, it exhibits the highest electrical conductivity, thermal conductivity, and reflectivity of any metal. Silver is found in the Earth's crust in the pure, free elemental form ("native metal, native silver"), as an alloy with gold and other metals, and in minerals such as argentite and chlorargyrite. Most silver is produced as a byproduct of copper, gold, lead, and zinc Refining (metallurgy), refining. Silver has long been valued as a precious metal. Silver metal is used in many bullion coins, sometimes bimetallism, alongside gold: while it is more abundant than gold, it is much less abundant as a native metal. Its purity is typically measured on a per-mille basis; a 94%-pure alloy is described as "0.940 fine". As one of the seven metals of antiquity, silver has had an enduring role in most human cultures. Other than in currency and as an in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Raman Scattering
In chemistry and physics, Raman scattering or the Raman effect () is the inelastic scattering of photons by matter, meaning that there is both an exchange of energy and a change in the light's direction. Typically this effect involves vibrational energy being gained by a molecule as incident photons from a visible laser are shifted to lower energy. This is called ''normal Stokes-Raman scattering''. Light has a certain probability of being scattered by a material. When photons are scattered, most of them are elastic scattering, elastically scattered (Rayleigh scattering), such that the scattered photons have the same energy (frequency, wavelength, and therefore color) as the incident photons, but different direction. Rayleigh scattering usually has an intensity in the range 0.1% to 0.01% relative to that of a radiation source. An even smaller fraction of the scattered photons (about 1 in a million) can be scattered ''inelastically'', with the scattered photons having an energy di ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Silver Nanoparticle
Silver nanoparticles are nanoparticles of silver of between 1 nm and 100 nm in size. While frequently described as being 'silver' some are composed of a large percentage of silver oxide due to their large ratio of surface science, surface to bulk silver atoms. Numerous shapes of nanoparticles can be constructed depending on the application at hand. Commonly used silver nanoparticles are spherical, but diamond , octagonal, and thin sheets are also common. Their extremely large surface area permits the coordination of a vast number of ligands. The properties of silver nanoparticles applicable to human treatments are under investigation in laboratory and animal studies, assessing potential efficacy, biosafety, and biodistribution. Synthesis methods Wet chemistry The most common methods for nanoparticle synthesis fall under the category of wet chemistry, or the nucleation of particles within a solution. This nucleation occurs when a silver ion complex, usually AgNO3 or ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chemiluminescence
Chemiluminescence (also chemoluminescence) is the emission of light (luminescence) as the result of a chemical reaction, i.e. a chemical reaction results in a flash or glow of light. A standard example of chemiluminescence in the laboratory setting is the luminol test. Here, blood is indicated by luminescence upon contact with iron in hemoglobin. When chemiluminescence takes place in living organisms, the phenomenon is called bioluminescence. A light stick emits light by chemiluminescence. Physical description As in many chemical reactions, chemiluminescence starts with the combining of two compounds, say A and B, to give a product C. Unlike most chemical reactions, the product C converts to a further product, which is produced in an electronically excited state often indicated with an asterisk: : A + B → C : C → D* D* then emits a photon (''h''ν), to give the ground state of D: I : D* → D + ''h''ν In theory, one photon of light should be given off for each mol ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Optical
Optics is the branch of physics that studies the behaviour and properties of light, including its interactions with matter and the construction of instruments that use or detect it. Optics usually describes the behaviour of visible, ultraviolet, and infrared light. Light is a type of electromagnetic radiation, and other forms of electromagnetic radiation such as X-rays, microwaves, and radio waves exhibit similar properties. Most optical phenomena can be accounted for by using the classical electromagnetic description of light, however complete electromagnetic descriptions of light are often difficult to apply in practice. Practical optics is usually done using simplified models. The most common of these, geometric optics, treats light as a collection of rays that travel in straight lines and bend when they pass through or reflect from surfaces. Physical optics is a more comprehensive model of light, which includes wave effects such as diffraction and interference that can ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
