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Current Trends on Role of Nano Particles on Pulmonary Diseases A IJRPC 2012, 2(3) Amulya et al ISSN: 22312781 INTERNATIONAL JOURNAL OF RESEARCH IN PHARMACY AND CHEMISTRY Available online at www.ijrpc.com Research Article CURRENT TRENDS ON ROLE OF NANO PARTICLES ON PULMONARY DISEASES A. Amulya*, V. Sirisha, CH. Babu Rao and Jaya Vaishnavi Chennam Don Bosco PG College of Pharmacy, 5th mile, Pulladigunta, Kornepadu(V), Vatticherukuru [M], Guntur, Andhra Pradesh, India. ABSTRACT In recent advances in nanotechnology engineering have given rise to rapid development of many novel applications in the biomedical field. The lung is one of the main route of entry for nano particles in to the body and hence a lightly site for accumulation of nanoparticles.In the present study the different types of nano materials for the preparation of nano particles and the use of nano particles in treatment of major pulmonary diseases like lung cancer.Pulmonary fibrosis Tuberculosis and Bronchial asthma and recent specific diagnostic test for lung cancer this article also includes about the present status in treatment of tuberculosis. Keywords: Nano particles, nano materials, lung cancer, tuberculosis, pulmonary fibrosis. 1. INTRODUCTION It is defined as a small object that behaves as widely accepted definitions at least one of their a whole unit in terms of its transports and dimensions must be less than 100nm but properties. Nanoparticles are particles that some intresting new applications use particles have one dimension that is 100 nanometers or of a few hundred nm so this report will not be less in size.The properties of many overly strict about the 100nm limit. conventional materials change when formed from nanoparticles. This is typically because 2. NANO MATERIALS nanoparticles have a greater surface area per 2.1Carbon nanotube weight than larger particles; this causes them Carbon nanotubes (CNTs) are allotropes of to be more reactive to certain other molecules carbon with a cylindrical nanostructure. [1] .Nanoparticles used for a very long time Nanotubes have been constructed with length- probably the earliest use begin in glazes for to-diameter ratio of up to 132,000,000:12-4 early Chinese procelian.A roman cup called significantly larger than for any other material. the Lycurges cup used nano sized gold These cylindrical carbon molecules have clusters to create different colors depending unusual properties, which are valuable for on whether it was illuminated from the front or nanotechnology, electronics, optics and other back. Carbon black is most famous example of fields of materials science and technology. a nano particulate material that has been Nanotubes are members of the fullerene produced in quantity for decades. structural family, which also includes the Roughly1.5million ton of material is produced spherical buckyballs, and the ends of a every year. Nanoparticles are currently made nanotube may be capped with a hemisphere out of a very wide variety of materials the most of the buckyball structure. Their name is common of the new generation of derived from their long, hollow structure with nanoparticles being ceramics which are the the walls formed by one-atom-thick sheets of best splits in to metal oxides ceramics such as carbon, called graphene. These sheets are titanium zinc aluminium and iron oxides to rolled at specific and discrete ("chiral") angles, name a prominent few and in the form of nano and the combination of the rolling angle and scale flakes of clay. According to the most radius decides the nanotube properties. 685 IJRPC 2012, 2(3) Amulya et al ISSN: 22312781 Nanotubes are categorized as single-walled discharge, laser ablation, high-pressure nanotubes (SWNTs) and multi-walled carbon monoxide (HiPco), and chemical vapor nanotubes (MWNTs). Individual nanotubes deposition (CVD). naturally align themselves into "ropes" held Most of these processes take place in vacuum together by van der Waals forces, more or with process gases . Large quantities of specifically, pi-stacking. nanotubes can be synthesized by these methods; advances in catalysis and 2.1a Single-walled continuous growth processes are making Most single-walled nanotubes (SWNT) have a CNTs more commercially viable. diameter of close to 1 nanometer, with a tube length that can be many millions of times Arc discharge longer. The structure of a SWNT can be During this process, the carbon contained in conceptualized by wrapping a one-atom-thick the negative electrode sublimates because of layer of graphite called graphene into a the high-discharge temperatures. Because seamless cylinder. The way the graphene nanotubes were initially discovered using this sheet is wrapped is represented by a pair of technique, it has been the most widely-used indices (n,m) . The integers n and m denote method of nanotube synthesis. the number of unit vectors along two directions The yield for this method is up to 30% by in the honeycomb crystal lattice of graphene. If weight and it produces both single- and multi- m = 0, the nanotubes are called zigzag walled nanotubes with lengths of up to 50 nanotubes, and if n = m, the nanotubes are micrometers with few structural defects. called armchair nanotubes. Otherwise, they are called chiral. The diameter of an ideal Laser ablation nanotube can be calculated from its (n,m) In the laser ablation process, a pulsed laser indices as follows vaporizes a graphite target in a high- temperature reactor while an inert gas is bled into the chamber. Nanotubes develop on the where a = 0.246 nm. cooler surfaces of the reactor as the vaporized SWNTs are an important variety of carbon carbon condenses. A water-cooled surface nanotube because most of their properties may be included in the system to collect the change significantly with the (n,m) value. nanotube. The laser ablation method yields Single-walled nanotubes are dropping around 70% and produces primarily single- precipitously in price, from around $1500 per walled carbon nanotubes with a controllable gram as of 2000 to retail prices of around $50 diameter determined by the reaction per gram of as-produced 40–60% by weight. temperature. 2.1b Multi-walled Chemical vapor deposition (CVD) Multi-walled nanotubes (MWNT) consist of During CVD, a substrate is prepared with a multiple rolled layers (concentric tubes) of layer of metal catalyst particles, most graphite. There are two models that can be commonly nickel, cobalt, iron, or a used to describe the structures of multi-walled combination. The metal nanoparticles can also nanotubes.In the Russian Doll model, sheets be produced by other ways, including of graphite are arranged in concentric reduction of oxides or oxides solid solutions. cylinders, e.g., a (0,8). In the Parchment The diameters of the nanotubes that are to be model, a single sheet of graphite is rolled in grown are related to the size of the metal around itself, resembling a scroll of parchment particles. This can be controlled by patterned or a rolled newspaper. The interlayer distance (or masked) deposition of the metal, in multi-walled nanotubes is close to the annealing, or by plasma etching of a metal distance between graphene layer. s in layer. The substrate is heated to graphite, approximately 3.4 Å. The Russian approximately 700°C. To initiate the growth of doll structure is observed more commonly. nanotubes, two gases are bled into the Double-walled carbon nanotubes (DWNT) reactor: a process gas (such as ammonia, form a special class of nanotubes because nitrogen or hydrogen) and a carbon-containing their morphology and properties are similar to gas (such as acetylene, ethylene, ethanol or those of SWNT but their resistance to methane). Nanotubes grow at the sites of the chemicals is significantly improved. metal catalyst; the carbon-containing gas is broken apart at the surface of the catalyst 2.1c Synthesis particle, and the carbon is transported to the Techniques have been developed to produce edges of the particle, where it forms the nanotubes in sizeable quantities, including arc nanotubes. This mechanism is still being 686 IJRPC 2012, 2(3) Amulya et al ISSN: 22312781 studied. The catalyst particles can stay at the Fabrication tips of the growing nanotube during the growth Self-assembled quantum dots are typically process, or remain at the nanotube base, between 5 and 50 nm in size. Quantum dots depending on the adhesion between the defined by lithographically patterned gate catalyst particle and the substrate. electrodes, or by etching on two-dimensional CVD is a common method for the commercial electron gases in semiconductor production of carbon nanotubes. For this heterostructures can have lateral dimensions purpose, exceeding 100 nm.Some quantum dots are the metal nanoparticles are mixed with a small regions of one material buried in another catalyst support such as MgO or Al2O3 to with a larger band gap. These can be so- increase the surface area for higher yield of called core-shell structures, e.g., with CdSe in the catalytic reaction of the carbon feedstock the core and ZnS in the shell or from special with the metal particles. forms of silica called ormosil. Quantum dots sometimes occur spontaneously in quantum 2.2 Quantum dot well structures due to monolayer fluctuations A quantum dot is a portion of matter (e.g., in the well's thickness.Self-assembled semiconductor) whose excitons are confined quantum dots nucleate spontaneously under in all three spatial dimensions. Consequently, certain conditions during molecular beam such materials have electronic properties epitaxy (MBE) and metallorganic vapor phase intermediate between those of bulk epitaxy (MOVPE), when a material is grown on semiconductors and those of discrete a substrate to which it is not lattice matched. molecules. They were discovered at the The resulting strain produces coherently beginning of the 1980s by Alexei Ekimov in a strained islands on top of a two-dimensional glass matrix and by Louis E.
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