Derivati naftilimida kao fluorescentni indikatori za ione teških metala

undergraduate thesis

• Title (english): Naphtalimide derivatives as fluorescent indicators for heavy metal ions
• Author: Mislav Matić
• Mentor: Ivana Steinberg (mentor)
• Mentor: Svjetlana Krištafor (mentor)
• Committee member: Svjetlana Krištafor (predsjednik povjerenstva)
• Committee member: Dragana Vuk (član povjerenstva)
• Committee member: Matija Cvetnić (član povjerenstva)
• Granter: University of Zagreb; Faculty of Chemical Engineering and Technology; Zagreb
• Defense date and country: 2020-09-24, Croatia
• Scientific / art field, discipline and subdiscipline: NATURAL SCIENCES; Chemistry

Abstract

Derivati 4-amino-1,8-naftilimida fluorescentni su spojevi koji primjenu pronalaze kao optički kemosenzori i kao komponente optičkih kemijskih senzora za detekciju raznih kemijskih vrsta. U ovome radu spektroskopski su ispitana dva nova derivata naftilimida, GJM-523 i GJM-525, a koje je sintetizirao Gerhard J. Mohr (Joanneum Research, Weiz, Austrija). Ispitan je potencijal primjene spojeva GJM-523 i GJM-525 kao pH osjetljivih fluorescentnih kemosenzora za metalne ione u vodenim otopinama primjenom UV-vidljive apsorpcijske i fluorescencijske spektrofotometrije. Optička svojstva derivata naftilimida proizlaze iz elektronske interakcije fluorofora i receptora vezanog putem amino dušika u položaju 4 u strukturi naftilimida mehanizmom fotoinduciranog prijenosa elektrona (PET). Vezanjem analita na receptor mijenjaju se fluorescencijska svojstva molekule ovisno o vrsti i koncentraciji analita. Ispitana je ovisnost fluorescentnog odziva spojeva GJM-523 i GJM-525 o pH vrijednosti vodenih otopina u rasponu 1,20 - 8,00 pri čemu intenzitet fluorescencije pravilno raste padom pH vrijednosti uslijed protoniranja amino dušika u strukturi piperazina u receptoru. Također, ispitan je fluorescentni odziv spojeva u prisutnosti metalnih iona u vodenim otopinama. Za spoj GJM-523 određen je mogući stehiometrijski omjer vezanja s ionima Cu2+ i Hg2+. Spoj GJM-525 ispitan je kao selektivni fluorescentni kemosenzor za Hg2+ ione uz praćenje vremenske ovisnosti intenziteta fluorescencije. Ispitivani derivati naftilimida imaju potencijal za primjenu kao fluorescentni kemosenzori za pH te za Cu2+ i Hg2+ ione u vodenim otopinama. Zbog mogućnosti kovalentne imobilizacije na celulozne i tekstilne materijale, spojevi su posebno zanimljivi kao moguće komponente nosivih senzora te je idući korak u istraživanju detaljna kinetička studija interakcije spojeva GJM-523 i GJM-525 s metalnim ionima, odnosno s ionima Cu2+ i Hg2+ te analiza kompleksa metala i naftilimida radi dobivanja punog uvida u mehanizam senzorskog odziva spojeva te optimizacija uvjeta ispitivanja.

Abstract (english)

Fluorescent 4-amino-1,8-naphthalimide derivatives found application as optical chemosensors or as components of optical chemical sensors for the detection of various chemical species. In this work, two new naphthalimide derivatives, GJM-523 and GJM-525, synthesized by Gerhard J. Mohr (Joanneum Research, Weiz, Austria), were examined as potential pH sensitive chemosensors for metal ions in aqueous solutions using UV-visible absorption and fluorescence spectrophotometry. The optical properties of naphthalimide derivatives result from the electronic interaction of the fluorophore and the amino nitrogen-coupled receptor at position 4 in the naphtalimide structure via photoinduced electron transfer (PET) mechanism. By binding the analyte to the receptor, a change in the fluorescence properties of the molecule occurs depending on the type and concentration of the analyte. The dependence of the fluorescent response of compounds GJM-523 and GJM-525 on the pH value of aqueous solutions in the range 1.20 - 8.00 was investigated, where the fluorescence intensity increases with decreasing pH value due to protonation of the amino nitrogen in the piperazine structure of the receptor. In addition, the fluorescent response of the compounds in the presence of metal ions in aqueous solutions was examined. A possible stoichiometric binding ratio for GJM-523 and Cu2+ and Hg2+ ions was determined. Compound GJM-525 was tested as a selective fluorescent chemosensor for Hg2+ ions with time dependence of fluorescence intensity being monitored. Due to the possibility of covalent immobilization on cellulose and textile materials, these compounds are particularly interesting as possible components of wearable sensors. The next step in research is a detailed kinetic study of the interaction of compounds GJM-523 and GJM-525 with metal ions and analysis of metal-naphtalimide complexes to gain full insight into the mechanism of sensory response of compounds and optimization of experimental conditions.

• Keywords: naftilimid; fluorescencija; pH vrijednost; metalni ioni
• Keywords (english): naphtalimide; fluorescence; pH value; metal ions
• Language: croatian
• URN:NBN: urn:nbn:hr:149:548309
• Study programme: Title: Applied Chemistry - Undergraduate study; specializations in: Environmental chemistry and green technologies, Advanced materials and technologies, Applied organic chemistry; Course: Applied organic chemistry; 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
• Created on: 2023-05-05 11:25:27