hrvatski

Sinteza i karakterizacija tiolno funkcionaliziranih nanočestica srebra i zlata

Za sintezu nanočestica srebra i zlata definiranih fizikalno-kemijskih svojstava ključno je odabrati prikladnu strategiju sinteze. Veličina, oblik i stabilnost nanočestica mogu se podešavati regulacijom molarnih omjera reaktanata te redoslijedom dodavanja reaktanata. U ovom radu su dvjema metodama sintetizirane nanoAg funkcionalizirane cisteinom ili glutationom te nanoAu funkcionalizirane cisteinom i glutationom. Karakterizacija i procjena stabilnosti provedena je primjenom različitih eksperimentalnih tehnika: atomske apsorpcijske spektroskopije (AAS), dinamičke metode raspršenja svjetlosti, elektroforetske metode raspršenja svjetlosti, transmisijske elektronske mikroskopije, te metode nuklearne magnetne rezonance. Otkriveno je da funkcionalizacija glutationom i cisteinom rezultira vrlo stabilnim nanočesticama srebra i zlata, uglavnom sfernoga oblika, čiji promjer i distribucija veličina izravno ovisi o molarnim omjerima reaktanata. Metodom nuklearne magnetske rezonancije zaključeno je da stabilizator ostvaruje strukturni kontakt sa nanočesticom preko tiolne i karboksilne skupine.

nanosrebro; nanozlato; glutation; cistein

In order to synthesize silver and gold nanoparticles with defined physical-chemical properties it is essential to choose an adequate sythesis strategy. Size, shape and stability of nanoparticles can be adjusted by regulating the molar ratios of reactants and the order of adding the reactants. In this thesis two methods were used to sythesize nanoAg functionalized by cysteine or glutathione and nanoAu functionalized by cysteine or glutathione. Characterization and evaluation of stability was conducted by using various experimental techniques: atomic apsorption spectroscopy (AAS), dynamic light scattering, electroforetic light scattering, transmission electron microscopy and nuclear magnetic resonance. It was discovered that functionalization by glutathione and cysteine results in very stable silver and gold nanoparticles, mostly spheric in shape, whose diameter and size distribution directly depends on the molar ratio of reactants. By using the nuclear magnetic resonance method it was discovered that the stabiliser forms structural contact with the nanoparticle through the thiole and carboxyle group.