Fluorescentna bojila temeljena na naftilimidu kao molekulski senzori za pH i ione teških metala

master's thesis

• Title (english): Naphtalimide-based fluorescent dyes as sensor molecules for pH and heavy metal ions
• Author: Marlena Grbić
• Mentor: Ivana Steinberg (mentor)
• Mentor: Lidija Furač (mentor)
• Committee member: Lidija Furač (predsjednik povjerenstva)
• Committee member: Svjetlana Krištafor (član povjerenstva)
• Committee member: Dragana Vuk (član povjerenstva)
• Granter: University of Zagreb; Faculty of Chemical Engineering and Technology; Zagreb
• Defense date and country: 2020-09-30, Croatia
• Scientific / art field, discipline and subdiscipline: NATURAL SCIENCES; Chemistry

Abstract

Kemijski senzori su uređaji koji kvalitativno ili kvantitativno određuju analite pretvarajući kemijsku informaciju o koncentraciji komponente uzorka u analitički koristan signal. Kod fluorescencijskih senzora mjeri se radijativni raspad, tj. emisija fluorofora. Rad senzora temelji se na selektivnom gašenju ili pojačanju intenziteta fluorescencije u dodiru s analitom (On-Off efekt). 4-amino-1,8-naftalimidi i njihovi derivati poznata su fluorescentna bojila. Postali su raznolika platforma za izradu senzora zahvaljujući svojima prednostima, poput optičkih svojstava, posebice snažna apsorbancija i emisija u vidljivom dijelu spektra, širok Stokesov pomak, visoka fotostabilnost i dr. Nadalje, ponašaju se kao tipični fluorofori s unutarmolekulskim prijenosom naboja (ICT), što omogućava osjetljivost na promjene u mikrookolišu. Posljednje, no jednako važno, je relativno jednostavna struktura, za čije dobivanje postoje dobro poznate sinteze. Svojstvo 1,8-naftalimidnih derivata je fotoinducirani prijenos elektrona (PET) s elektron donora na karbonilnu skupinu fluoroforske jedinice. PET smanjuje stopu radijativnog raspada. Ovisno o strukturi derivata, može doći do pojačanja ili smanjenja fluorescencije. U radu je proučen mehanizam djelovanja fluorescencijskih PET senzora temeljenih na skupini derivata 1,8-naftalimida, pri čemu utjecaj na emisiju mogu imati položaj supstituenta u strukturi, udaljenost elektron donora i akceptora, sklonost supstituenta za specifičnim interakcijama te geometrija liganada. Posebno su proučena optička svojstva u otopinama različitih kationa i pH, u svrhu izrade senzora. Navedene su metode imobilizacije na pamučnu, polimernu, staklenu podlogu, na molekulska sita i celulozne nanočestice te su uviđene prednosti kovalentne imobilizacije. Zahvaljujući pokazanim obećavajućim karakteristikama, fluorescencijski senzori temeljeni na 1,8-naftalimidima mogli bi se koristiti u realnim uzorcima vode različitog podrijetla.

Abstract (english)

Chemical sensors are devices which can detect or measure analytes by converting chemical information about the concentraction of a component in a sample into an analitically useful signal. Fluorescent sensors measure radiative decay, that is emission of a fluorophore. The main characteristic of those sensors is selective quenching or increasing of the fluorescence intensity when in contact with an analyte (On-Off effect). 4-amino-1,8-naphthalimides and their derivatives are commonly used fluorescent dyes. They became versatile platforms for sensor design due to their advantageous optical properties, such as strong absorption and emission in the visible region, large Stokes shift, high photostability etc. Secondly, they are typical fluorophores with intermolecular charge transfer, which enables sensitivity to changes in the microenviroment. Lastly, but equally important, they have relatively simple structure, for which facile synthesis have been established. Property of 1,8-naphtalimide derivatives is photoinduced electron transfer (PET), which occurs from electron donor to carbonyl groups located on a fluorophore. PET process decreases the rate of the radiative decay. Depending on the structure of the derivative, either increase or quenching of fluorescence can occur. In this paper the mechanism of fluorescent PET sensors containing the derivatives od 1,8-naphthalimides is studied, where different aspects can influence its properties, such as position of the supstituent, distance of electron donor and acceptor, specific interactions and the ligand geometry. The great emphasis is on optical properties in solutions of different metal cations and pH, making the base of sensoric design. In addition, immobilisation methods to different substrates are listed; cotton fabric, polymers, glass, molecular sieves and cellulose nanoparticles, where covalent bonding has great advantages. Due to the promising characteristics shown, 1,8-naphthalimide-based fluorescence sensors could be used in actual water samples of different origins.

• Keywords: fluorescencijski senzori; 1 8-naftalimidi; PET proces; imobilizacija
• Keywords (english): fluorescent sensors; 1 8-naphtalimides; PET process; immobilisation
• Language: croatian
• URN:NBN: urn:nbn:hr:149:618742
• Study programme: Title: Applied Chemistry - Graduate study; specializations in: Environmental chemistry and green technologies, Advanced materials and technologies, Applied organic chemistry; Course: Advanced materials and technologies; Study programme type: university; Study level: graduate; Academic / professional title: magistar/magistra primijenjene kemije (magistar/magistra primijenjene kemije)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Access restricted to students and staff of home institution
• Created on: 2022-03-02 14:41:50