Silika nanočestice dopirane organskim bojilima

undergraduate thesis

• Title (english): Dye-doped silica nanoparticles
• Author: Matija Galjer
• Mentor: Ivana Steinberg (mentor)
• Committee member: Ivana Steinberg (predsjednik povjerenstva)
• Committee member: Petar Kassal (član povjerenstva)
• Committee member: Anamarija Rogina (član povjerenstva)
• Granter: University of Zagreb; Faculty of Chemical Engineering and Technology; Zagreb
• Defense date and country: 2015-07-17, Croatia
• Scientific / art field, discipline and subdiscipline: NATURAL SCIENCES; Chemistry; Applied Chemistry

Abstract

Nanotehnologija je znanstveno područje od rastuće važnosti i interesa. Cilj ovog rada
je upoznavanje i predstavljanje njegovog specifičnog dijela - silika nanočestica, čija su
svojstva još uvijek nepotpuno istražena, a pronalaze potencijalnu primjenu u mnogim
znanstvenim, medicinskim i tehnološkim područjima. U skladu sa znanstvenim
istraživanjima koja se provode na Zavodu za opću i anorgansku kemiju, provedena je sinteza
i karakterizacija silika nanočestica, silika nanočestica dopiranih organskim bojilima te
istraživanje njihovih svojstava kao potencijalnih pH senzora.
Sinteza silika nanočestica provedena je modificiranom Stöberovom metodom (sol – gel
pristupom). Organska bojila korištena za pripravu dopiranih nanočestica su rodamin B i 2-
piperidinilbenzimidazo[1,2-a]kinolin-6-karbonitril (spoj 1), derivat benzimidazola pripravljen
na Zavodu za organsku kemiju FKIT-a. Optimizacija priprave silika nanočestica dopiranih
organskim bojilom provedena je na primjeru nanočestica dopiranih rodaminom B. Prema
postupcima dostupnim u literaturi, nanočestice dopirane rodaminom B pripravljene su na tri
različita načina; jednostavnim dodavanjem bojila u sol – gel proces, dodavanjem bojila uz
prekursor (3-aminopropil)trietoksilan (APTES) te dodavanjem bojila, prethodno
funkcionaliziranog silanolnim grupama, u sol – gel proces. Utvrđena je veličina i raspodjela
pripravljenih nanočestica pretražnom elektronskom mikroskopijom, te apsorbancija i
fluorescencija u UV-Vis dijelu spektra. Pripravljene čestice su veličine nanodimenzija te su
monodisperzne. Spektralna analiza nanočestica s rodaminom nije bila uspješna zbog bliskih
vrijednosti emisijske i apsorpcijske valne duljine zračenja, no utvrđeno je da bojilo ostaje
vezano na nanočesticu, zbog čega silika može bili dobar nosač za bojilo rodamin.
Nanočestice dopirane organskim bojilom 1 pripravljene su prema prethodno optimiziranom
postupku. Veličina i raspodjela pripravljenih nanočestica utvrđena je pretražnom
elektronskom mikroskopijom, a utvrđene su i apsorbancija i fluorescencija u UV-Vis dijelu
spektra. Također je kvalitativno ispitan utjecaj pH na spektralna svojstva pripravljenih
nanočestica.

Abstract (english)

Nanotechnology is a scientific field of growing importance and interest. The aim of
this work was introduction of its specific segment - silica nanoparticles, of which properties
yet have not been completely examined, but are applicable in many scienfitic, medical and
technological areas. synthesis and characterization of silica nanoparticles, dye-doped silica
nanoparticles and examining their properties as potential pH sensors have been done.
The synthesis of silica nanoparticles included the modified Stöber method (the sol-gel
approach). Rhodamine B and 2-piperidinylbenzimidazo[1,2-a]quinoline-6-carbonitrile
(compound 1), the derivative of benzimidazole prepared at the Institute of organic chemistry
at Faculty of Chemical Engineering and Technology, have been used as organic dyes for the
synthesis. Preparation of dye-doped silica nanoparticles has been optimized in accordance
with nanoparticles doped with Rhodamine B. As reported in previous works, nanoparticles
containing Rhodamine B were being prepared in three separate ways: by simply adding the
dye to the sol – gel process, by adding the dye including a precursor (3-
aminopropyl)triethoxysilane (APTES), and by adding the dye which had been previously
functionalized with silanol groups, to the sol – gel process. The size and distribution of the
prepared nanoparticles has been determined by scanning electron microscope, and by
absorption and fluorescence in the UV- visible part of the spectrum. It has been found that the
particles were in nanodimensions, and that they are monodispersed. Spectral analysis of the
nanoparticles containing Rhodamine was unsuccessful due to adjasent values of emitting and
absorbing wavelength. Still, the dye remained intact with the surface of the silica
nanoparticles, and in that matter, silica can be considered as a good carrier for Rhodamine
dye.
Nanoparticles doped with compound 1 were prepared according to the optimized procedure.
The size and distribution of prepared nanoparticles has been determined by scanning electron
microscope, and by absorption and fluorescence in UV-visible part of the spectrum.
Likewise, the changes in optical properties of prepared nanoparticles caused by changing the
pH value have been examined.

• Keywords: silika nanočestice; organska bojila; optički senzori
• Keywords (english): silica nanoparticles; organic dyes; optical sensors
• Language: croatian
• URN:NBN: urn:nbn:hr:149:213576
• Study programme: Title: Applied Chemistry - Undergraduate study; specializations in: Environmental chemistry and green technologies, Advanced materials and technologies, Applied organic chemistry; Course: Environmental chemistry and green technologies; Study programme type: university; Study level: undergraduate; Academic / professional title: sveučilišni/a prvostupnik/prvostupnica (baccalaureus/baccalaurea) primijenjene kemije (sveučilišni/a prvostupnik/prvostupnica (baccalaureus/baccalaurea) primijenjene kemije)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Open access
• Repository: Repository of Faculty of Chemical Engineering and Technology University of Zagreb
• Created on: 2016-09-19 13:26:05