Biosynthesis of Nanocomposites Using Leaf Extract

Bio price reduction of Nanocomposites Using Leaf Extract sn arVarious nanoparticles and nanocomposites have been synthesized using alternate extract and evaluated for their antibacterial drug drug activity. This suss extinct intends to present biogenesis of nanocomposites using peruse extract. Here, I have discussed bio tax write-off methods of polymer nanocomposites using leaf extract. The voltage of nanotechnology and biological science together is enormous. in that respect argon many potential antibacterial applications of nanocomposites such as in disinfectant textiles, nutrient preservation, scratch disinfection, hack fertilisations, safe cosmetics, medical devices, drug carriers, dental fillers and adhesives, pee treatment etc. In recent long time nanocomposite aims have been studied for wound dressing. I have discussed a bionanocomposite film and hydrogel that have application in wound dressing.CHAPTER 1INTRODUCTION1.1 NanotechnologyNanotechnology is a branch of science and technology that deals with matter of size 1-100nm. Since then on that point has been lot of advancement in nanotechnology. Nanotechnology has applications in almost every written report such as electronics, medicine, bio fabrics, energy production etc. When a seeable corporeal changes to nanomaterials, properties such as electrical, mechanical, optical, catalytic, medicinal, biological etc change. Gold which does not defend with other chemicals easily at normal scales acts as a estimable catalyst when converted to nanoscale.1.2 Nanoscale materialsNanoscale materials complicate materials which posses at least one attribute in the nanometer range i.e. 1-100nm. The key characteristics defining the potential applications of nanoscale materials include the followingHigher scratch areaHigher chemical responsivenessBetter catalytic propertiesBetter adsorptionVariety of chemical tax write-off routes.Natural and synthetic strategies1.3 NanocompositesNanocomposites are materials made from two or much individual components with properties different from each other, which when combined produce a material with properties completely different from the individual materials. A nanocomposite consists of two or more phases where one phase is monolithic (single crystal) into which the reinforcement are introduce. The monolithic material is cognise as a matrix. Reinforcement, in a nanocomposite is a nanosized materials embedded into the parent material called matrix. Nanocomposites are broadly classified into three typesa) ceramic-matrix nanocompositesb) alloy-matrix nanocompositesc) polymer-matrix nanocompositesd) veil metallic matrix nanocomposites.CHAPTER 2BIOSYNTHESIS OF NANOCOMPOSITE USING LEAF extinguishNanoparticles are being apply in many sectors of the economy and it is principal(prenominal) to consider the biological and environmental safety of their production. The main methods for nanoparticle synthetic thinking are chemical and phy sical approaches and these approaches are often expensive and potentially calumniatory to the environment. Green synthesis approach has been pursued in recent geezerhood as an alternative, inexpensive, efficient, and environmentally safe method for synthesizing nanoparticles with specific properties. The main management is on the role of the natural whole caboodle (leaf) extracts involved in the bioreduction and capping of metal salts during the nanocomposite synthesis. Many researchers have reported the biosynthesis of nanoparticles by leaf extracts and their potential applications in confused fields.2.1 Commonly utilize leaf extracts for synthesis of nanocomposites binomial name Murraya koenigiiCommon secern Curry TreeFamily epithet family RutaceaeDescription Curry tree is native to India and Sri Lanka. The leaves ofMurraya koenigiiare used as an herbinAyurvedic medicine because of its antioxidant, anti-diabetic, antimicrobic, anti-inflammatory, anti- hypercholesterolemi c properties. Curry leaves recently been found to be as a potent antioxidant due to high slow-wittednesss of carbazoles, a peeing meltable heterocyclic compound. Carbazoles found in leaf extract may be responsible for the reduction and stabilization of metal ions. Further research is prerequisite to explain and extend the reduction mechanism of Murraya koenigii leaf extract for make headway application.Binomial Name Tridax procumbensCommon Name Coat buttons or Tridax DaisyFamily Name AsteraceaeDescription Tridax procumbens is a giganticspread weed and pest plant native to America. The plant has various medicinal properties. Tridax procumbens is rich in alkaloids, flavanoids, carotenoids and tannins. It is used in nanoparticle synthesis as it has high lists of ketones, amines, phenols, lactones and alkanes which are capable of trim back metal ions.Binomial Name genus Ficus benghalensisCommon Name banian tree TreeFamily MoraceaeDescription Banyan tree is a broadleaf tree fo und throughout the forest tract of India, in sub-Himalayan region. Ficus benghalensis is widely used for its medicinal properties. Ficus benghalensis leaf extract has proteins/enzymes which geld the metal ions and it also contains reducing sugars such as flavanones which provide stability to the nanoparticles.Binomial Name Calotropis giganteanCommon Name Crown FlowerFamily Name ApocynaceaeDescription Calotropis gigantean is a large shrub rich in metabolites responsible for reduction metal ions. Organic compounds like alkaloids, polyphenols, and proteins present in plant extracts are capable of reducing and capping nanoparticles.Binomial Name genus genus Catharanthus roseusCommon Name Madagascar periwinkleFamily Name ApocynaceaeDescription Catharanthus roseus is a medicinal subshurb. Catharanthus roseus contains more than 70 alkaloids.2.3 Nanocomposites synthesized using leaf extractA broad spectrum of leaf extracts can be employ for the biosynthesis of nanoparticles. In this sect ion I have briefly discussed synthesis of two polymer-matrix nanocomposites using leaf extract. In both the examples, reinforcement is facile-tongued nanoparticle and the matrix of the nanocomposite is a polymer.2.3.1 Ag impregnated Microcrystalline Cellulose Bionanocomposite film bills nanoparticles are impregnated into microcrystalline cellulose to form a nanocomposite. Curry leaf extract is used for the bioreduction and capping of silver nanoparticles. First 0.001M silver treat resolving power is prepared in 1000 mL of deionised water supply. 10 g of microcrystalline cellulose is added to the silver treat solution and sonicated for 10 minutes. 50 mL of curry leaf breed is added to the multifariousness and the mixture is stirred for 6 hours. bills ions are trim back to silver by curry leaf extract. Reduced silver nucleates in to the silver nanoparticles on the microcrystalline fibrils. After 6 hours the mixture is allowed to ratify down and unnecessary reaction mixtur e is decanted. The silver nanoparticles impregnated microcrystalline cellulose is water-washed with deionized water and ethanol and then dried in oven at 55C over night.The formation of silver nanoparticles is confirmed by UV-vis spectra as the peak is observed at 430 nm. The colour of microcrystalline cellulose is white and later impregnation of silver on it, it changes to yellowish brown.0.5 g of polylactic acid is fade out in 20 mL of chloroform with moderate heating and invariable stirring for 30 minutes. The dried silver nanoparticle coated microcrystalline mill is added in 5%, 10% and 20% w/w assiduity to separate samples. The polylactic acid is stirred with silver impregnated microcrystalline cellulose for a daytime to allow for dispersion. The mixture is poured to glass Petri salmon pink and left to evaporate. When the chloroform evaporates, the flexible film is removed and collected from Petri dish. Silver impregnated microcrystalline bionanocomposite film is obtain ed. 62.3.2 Silver/Starch-co-polyacrylamide hydrogel nanocompositeGelatinized starch solution is prepared by mixing a known amount of starch powder in 10 mL of deionized water and 1 mL of 0.5 mL of 0.5 M atomic number 11 hydroxide solution. The mixture is heated at 90C for 10 minutes in a water bath with continuous stirring. A predetermined amount of maleic acid is then added to the gelatinized starch solution. The mixture of gelatinized starch and maleic acid is further heated at 80C in a water bath for 4 hours. Then acrylamide is added and stirred for 30 minutes at 50C. After that initiator (potassium persulfate or KPS) and crosslinker (methylenebisacrylamide or MBA) is added. finally, an aqueous solution of tetramethylenediamide (TEMED) is added to the solution and for another 10 minutes same temperature is maintained. The synthesized co-polymeric hydrogel is taken out after the completion of free radical polymerization. Then the synthesized co-polymeric hydrogel is immersed in manifold distilled water at room temperature for a day to remove excess of unreacted reagents and monomers present in hydrogel network. To remove the residue effectively the double distilled water is refreshed for every 12 hours. At last the hydrogel is dried at ambient temperature for 48 hours.Precisely weighed dried starch-co-polyacrylamide hydrogel is equilibrated with double distilled water for 48 hours and instantly transferred to a beaker containing 100 mL of 0.005 M silver nitrate solution and then equilibrated for 24 hours. During this process the silver ions are change from solution into free network spaces of co-polymeric hydrogel. To a beaker containing 50 ml Tridax procumbens leaf extract, hydrogel with absorbed silver ions is added and kept for 24 hours. Reduction of silver ions into silver nanoparticles occurs and hydrogel turns into brown colour. The brown colour confirms the formation of silver nanoparticles in hydrogel matrix. 7CHAPTER 3ANTIBACTERIAL ACTIVITY OF NANOCOMPOSITES SYNTHESIZED USING LEAF EXTRACTDue to the rebellion concerns of bacterial infections, there is a growing need to develop untried and powerful antibacterial agents. Mainly, nanoparticles have been applied in burn dressings, cosmetics, food preservation, medical devices, water treatment etc. There is a wide bioapplication of nanoparticles. It has been recognized that the bactericidal effect of nanoparticles is dependent on their size, size distribution, shape, morphology, surface functionalization, and their stability. Additionally, the use of inorganic nanoparticles as antimicrobial agents has numerous benefits such as enhanced stability and safety in contrast with the organic antimicrobial agents. Green synthesis and functionalization of nanoparticles enhances their antibacterial activity and improves their stability.In this section antibacterial activity of silver/polymer film and hydrogel is discussed. So the antibacterial activity of nanocomposites is enhanced.3.1 antibacterial drug activity of Ag impregnated Microcrystalline Cellulose Bionanocomposite filmThe PLA/MCC sample was tested for antimicrobial activity using Charm disk assay. Firstly an nutrient agar headquarters was seeded with group B stearothermophilus. Then small circular pieces of the films were placed on the seeded agar and incubated. Indicators are present in agar which signifies the stipulation of microbial growth. Yellow colour indicates the microbial growth and purple indicates the prohibition era. The sign analysis shows that the film exhibits considerable antibacterial properties. 63.2 Antibacterial activity of Silver/Starch-co-polyacrylamide hydrogel nanocompositeThe antibacterial activity of SNCH was evaluated by disc diffusion technique against positive and gram-negative bacteria such as Bacillus and Escherichia coli. Firstly, nutrient agar medium was prepared by mixing beef extract (3 g), peptone (5 g) and sodium chloride (5 g) in 1000 mL distilled water. The pH of the medium was adjusted to 7. Finally agar (15 g) was added to the prepared solution and then medium was sterilized in an autoclave at a pressure of 15 lbs for 30 minutes at 121C. This medium was then transferred into a sterilized glass Petri dish in a laminar air flow chamber. After the media solidified, Escherichia coli and Bacillus culture (50L) was spread on the solid surface of the media. Paper discs (6mm diameter) were taut in the test compounds (20mg/20mL) overnight. Then these discs were loaded on culture plates. The plates were incubated for 24 hours at 37C. The inhibition zone appears around the disc which shows the antibacterial effect of SNCH. 7Pure hydrogels are generally inefficient for antibacterial activity. It is seen that smaller the size of silver nanoparticle greater is the antibacterial activity. .The SNCH having low silver nanoparticles concentration still showed excellent antibacterial activity against gram-positive and gram-negative bactericide. This results into inhibition of bacterial cell growth. So SNCH nanocomposites can be used as successful antibacterial agents such as wound-dressing materials. 7Modern wound dressing theory, suggests promoting dynamic equilibrium between exudate absorption and optimal surface moisture at the wound surface. In addition, it should be able to commuting gas to provide the wound with adequate oxygen tension.3.3 Mechanism of antibacterial activity of nanoparticlesAntibacterial activity is a property due to which compounds are capable to annihilate or slow down the bacterial growth, without cause toxicity to host cells. Such agents are classified as a) bactericidal, which kill bacteria, 2) bacteriostatic, which slow down the bacterial growth. The exact mechanism of nanoparticle toxicity against various types of bacteria is not completely evaluated yet. It is proposed that nanoparticles attach themselves to bacterial membrane by electrostatic interaction and disrupt its integrity. Nanotoxici ty is triggered by the initiation of oxidative stock by free radical formation, i.e. ROS, followed by the administration of nanoparticles. The nanoparticle toxicity depends on composition, intrinsic properties, surface modification of the bacterial species and the physical and chemical properties of nanoparticles, indicating the mechanisms to be highly complex.The antibacterial mechanisms of nanomaterials is not fully elucidated, but the existing archetype suggests various combinations of processes that can occur (1) ions are released which is followed by cellular inhalation and a cascade of intracellular reactions, (2) extracellular and intracellular generation of ROS and (3) get up interactions between nanoparticles and cell membrane. At sub-micromolar concentrations, ions are internalized and they react with the thiol groups of cellular proteins, which corpus to uncoupling of ATP synthesis from respiration, loss of proton motive force, and interference with the phosphate ef fluence system. At millimolar levels, nanoparticles induce detachment of the cell wall from the cytoplasm, possibly release the intracellular content, DNA condensation and loss of replication ability. ROS produces oxidative speech pattern which results in lipid membrane and DNA damage. Finally, nanoparticles increase the cell membrane permeability and, subsequently, penetrate inside cells to induce any one or the entire cascade of effects mentioned above. 9CONCLUSIONThe most important heading of nanobioscience involves application of nanotools to relevant biological and medical problems and refining these applications. The use of microorganisms and plants for synthesis of metal nanoparticles is of great interest. In contrast to chemical and physical synthesis methods, biological processes for synthesizing nanomaterials can be achieved in aqueous phase in gentle and environment friendly conditions. This approach has become attractive concentrate on in current green nanotechnology . With the help of this approach we can synthesize nanomaterials in less toxic way as it replaces toxic chemical reducing and capping agents. Inorganic nanoparticles naturally possess bacteria-killing properties, but by modifying the inorganic nanoparticles i.e. forming nanocomposites, these properties can be enhanced. In the biomedical field, a synthesis of nanocomposite films and hydrogels by a green process was developed to enhance the inactivation of bacteria in wounds. There are also other potential antibacterial applications of nanocomposites such as in antimicrobial textiles, food preservation, surface disinfection, burn dressings, safe cosmetics, medical devices, drug carriers, dental fillers and adhesives, water treatment etc. Further research on nanocomposites capable of antibacterial activity is necessary for large scale commercial application