Termodinamička i strukturna karakterizacija kompleksa ciklopeptida s kolorimetrijskim i fluorescentnim anionskim bojama

master's thesis

• Title (english): Thermodynamic and structural characterization of cyclopeptide complexes with colorimetric and fluorescent anionic dyes
• Author: Lucija Otmačić
• Mentor: Gordan Horvat (mentor)
• Committee member: Gordan Horvat (predsjednik povjerenstva)
• Committee member: Iva Juranović Cindrić (član povjerenstva)
• Committee member: Aleksandra Maršavelski (član povjerenstva)
• Committee member: Vladislav Tomišić (član povjerenstva)
• Granter: University of Zagreb; Faculty of Science; (Department of Chemistry); Zagreb
• Defense date and country: 2024-02-16, Croatia
• Scientific / art field, discipline and subdiscipline: NATURAL SCIENCES; Chemistry

Abstract

U ovom su radu ispitana spektroskopska i strukturna svojstva te termodinamička stabilnost kompleksa homociklopentapeptida s kolorimetrijskim i fluorescentnim anionskim bojama u acetonitrilu pomoću spektrofluorimetrijskih i spektrofotometrijskih titracija i simulacija molekulske dinamike. Kao ciklopeptidi korišteni su ciklopentafenilalanin, ciklopentaleucin i derivat ciklopentalizina čije su amino skupine na bočnim ograncima zaštićene BOC skupinama. Kao reprezentativni anioni sulfonatnih fluorescentnih boja korišteni su 8-anilino-1-naftalensulfonska kiselina i alizarin crveno S, a kao reprezentativni anion sulfonatnih kolorimetrijskih boja korišten je metiloranž. Kao reprezentativni anioni karboksilatnih fluorescentnih boja korištene su N-acetilirane aromatske amino kiseline triptofan i fenilalanin. Rezultati upućuju na stvaranje stabilnih kompleksa između ciklopepentaleucina i derivata ciklopentalizina sa sulfonatnim i karboksilatnim fluorescentnim i kolorimetrijskim bojama, dok je u slučaju ciklopentafenilalanina afinitet prema fluorescentnim karboksilatnim bojama nešto viši. Kod nastalih kompleksa ciklopeptida s fluorescentnim sulfonatnim i karboksilatnim bojama u većini slučajeva opažena je značajna razlika u molarnim spektrima kompleksa, dok ta razlika nije uočena kod kompleksa s kolorimetrijskom sulfonatnom bojom. Također, rezultati provedenih MD simulacija u otapalu upućuju na koordinaciju aniona preko amidnih protona ciklopeptida.

Abstract (english)

In this work, spectroscopic and structural properties, as well as thermodynamic stability of homocyclopentapeptide complexes with colorimetric and fluorescent anionic dyes in acetonitrile were examined by means of spectrofluorimetric and spectrophotometric titrations and molecular dynamics simulations. As cyclopeptides, cyclopentaphenylalanine, cyclopentaleucine and cyclopentalysine derivative with BOC protected amino group side chains were used. 8-anilino-1-naftalenesulfonic acid and alizarin red S were used as sulfonic fluorescent dyes representatives, while methyl orange was used as sulfonic colorimetric dye representative. N-acetylated aromatic amino acids tryptophan and phenylalanine were used as carboxylic fluorescent dyes representatives. The results indicate that both of cyclic peptides form stabile complexes with fluorescent and colorimetric sulfonic and carboxylic dyes, while the affinity of cyclopentaphenylalanine towards fluorescent carboxylic dyes is somewhat higher. In most cases a significant difference in molar spectra of fluorescent dye complexes with both peptides were observed. That significant difference was not observed with colorimetric anion dye complexes. Also, the results obtained by MD simulations indicate that the anions are coordinated by the amide protons of the peptide.

• Keywords: ciklopeptidi; fluorescentne boje; kolorimetrijske boje; simulacije molekulske dinamike; spektrofluorimetrija; spektrofotometrija; vezanje aniona
• Keywords (english): anion binding; colorimetric colors; cyclopeptides; fluorescent colors; molecular dynamics simulation; spectrofluorimetry; spectrofotometry
• Language: croatian
• URN:NBN: urn:nbn:hr:217:576107
• Project: Number: IP-2019-04-9560; Title: Koordinacijske reakcije makrocikličkih liganada u otopini; Title: Coordination Reactions of Macrocyclic Ligands in Solution; Acronym: MacroSol; Leader: Vladislav Tomišić; Jurisdiction: Croatia; Funder: HRZZ; Funding stream: IP
• Study programme: Title: Graduate university studies in chemistry; specializations in: Graduate university studies in chemistry; Course: Graduate university studies in chemistry; Study programme type: university; Study level: graduate; Academic / professional title: sveučilišni/a magistar/magistra kemije (sveučilišni/a magistar/magistra kemije)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Embargoed access; Embargo expiration date: 2026-02-16
• Created on: 2024-03-12 12:24:16