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99 Fabrication of Tragacanth Nanoparticles through Electrospraying Jinoos Javadi j javadi@tx iut ac ir Date of Submission Department of Textile Engineering Isfahan University of Technology Isfahan 8415683111 Iran Degree M Sc Language Farsi Supervisor Prof H Tavanai tavanai@cc iut ac ir Prof M Morshed morshed@cc iut ac ir Prof A Allafchian allafchian@cc iut ac ir Abstract Traganth is a biocompatible and biodegradable polysaccharide which has attracted the attention ofresearchers in different fields like cosmetics hygiene tissue engineering drug release food textiles andpharmaceuticals It is well known that particles with submicron size show totally different characteristics andbehavior in comparison to their bulk form Nanoparticles can be produced through processes likeemulsification coacervation and electrospraying It is believed that electrospraying is capable of producingspherical smaller and more uniform particles In order to electrospray polymeric particles at first thepolymer must be dissolved in a suitable solvent or a mixture of solvents if needed The polymer solution isthen fed by a fine metering system to the tip of the nozzle in an electric field produced by a high voltagepower supply The electric forces induced on the drop at the exit of the nozzle overcome the surface tensionof the drop and the initial breaking up occurs After the evaporation of the solvent the size of the drop isdecreased and these initial drops break up to smaller and smaller drops due to the repulsion of theelectrostatic forces on the drops as they travel from the tip of the nozzle to the collector This breaking up isknown as coulombic explosions Electrospraying has been employed to produce nanoparticle such aschitosan insulin fibroin sericin and keratin nanoparticles Up to now traganth as well as traganthh oligochitosan has been produced by colloidal solution process However literature shows no report onelectrosprayed traganth nanoparticles This research aimed at electrospraying traganth nanoparticles In orderto carry out this task traganthh in water and water ethanol 70 30 were electrosprayed and the effect ofparameters such as viscosity applied voltage nozzle collector distance feed rate and the kind of solventwere studied on the morphology of the electrosprayed traganth nanoparticles The range for traganthconcentration nozzle collector distance voltage and feed rate was 0 1 0 3 w v 10 20 cm 15 25 and0 02 0 06 ml respectively These data were obtained by trial and error experiments as there was noinformation already available in this field In the second part of this research the soluble part of traganthh inwater was separated by deesterification with sodium hydroxide The water soluble traganth was alsoelectrosprayed The results showed that electrospray is capable of producing nanoparticles with an average size in therange of 30 50 nm depending on the electrospraying conditions The water soluble traganth gave rise toeven smaller particles As the viscosity of water soluble traganth was low electrospraying of traganth withconcentrations of even 2 was possible It was also found that lowering feed rate increasing nozzlecollector distance and voltage decreases the average size of the electrosprayed traganth nanoparticles FTIRproved the absence of ester groups after deestrification FTIR for electrosprayed nanoparticles showed ahigher intensity for C O at 1417 wave number XRD studies showed an amorphous or very small crystallitesfor traganth but water soluble traganth was capable of crystallizing Key words tragacanth nanoparticles electrospraying particle size FTIR XRD

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توليد نانو پودر كتيرا با استفاده از روش الكترواسپري

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