Istraživanje interakcija berberina i papaverina s ribonukleotidima SERS spektroskopijom

master's thesis

• Title (english): Study of berberine and papaverine interactions with ribonucleotides by SERS spectroscopy
• Author: Patricia Tikvenjak
• Mentor: Snežana Miljanić (mentor)
• Committee member: Aleksandra Maršavelski (predsjednik povjerenstva)
• Committee member: Snežana Miljanić (član povjerenstva)
• Committee member: Željka Soldin (član povjerenstva)
• Committee member: Adriana Kenđel (član povjerenstva)
• Granter: University of Zagreb; Faculty of Science; (Department of Chemistry); Zagreb
• Defense date and country: 2022-09-30, Croatia
• Scientific / art field, discipline and subdiscipline: NATURAL SCIENCES; Chemistry

Abstract

Istraženo je površinski pojačano Ramanovo raspršenje alkaloida (berberin i papaverin),
ribonukleotida (AMP, GMP, CMP, UMP) i njihovih kompleksa u koloidu srebra
pripravljenom redukcijom srebrova nitrata s trinatrijevim citratom i agregiranom
magnezijevim sulfatom. Na temelju koncentracijski ovisnih SERS spektara predloženi su
mehanizmi adsorpcije molekula na nanočestice srebra. Alkaloidi se adsorbiraju na površinu
nanočestica uslijed privlačnih elektrostatskih interakcija između pozitivnog naboja u strukturi
molekula te negativnog naboja stabilizirajućeg sloja citratnih iona, dok ribonukleotidi
najvjerojatnije zamjenjuju citratne ione na površini i dušikovom bazom ostvaruju vezu s
površinom srebra. Spektralne promjene u SERS spektrima kompleksa pripravljenih u
molarnom omjeru [alkaloid]/[ribonukleotid] = 1/1 analizirane su u odnosu na izračunati
spektar zbroja SERS spektara pojedinih molekula. Opažene promjene SERS intenziteta
upućuju na nastanak kompleksa i njegovu orjentaciju na površini nanočestica srebra, međutim
jednoznačno ne ukazuju na vrstu interakcija između alkaloida i ribonukleotida.

Abstract (english)

Surface-enhanced Raman scattering of alkaloids (berberine and papaverine), ribonucleotides
(AMP, GMP, CMP, UMP) and their complexes was studied in silver colloid prepared by
reduction of silver nitrate with trisodium citrate and aggregated with magnesium sulfate.
Based on concentration-dependent SERS spectra, the adsorption mechanisms of molecules on
silver nanoparticles were suggested. Alkaloids were adsorbed on the nanoparticles surface due
to attractive electrostatic interactions between the positive charge in the structure of the
molecules and the negative charge of the stabilizing layer of citrate ions, while
ribonucleotides most likely replaced citrate ions on the surface and formed a bond with the
silver surface via the nitrogen base. Spectral changes in the SERS spectra of the complexes
prepared in the molar ratio [alkaloid]/[ribonucleotide] = 1/1 were analyzed with respect to the
calculated spectrum of the sum of the SERS spectra of individual molecules. The observed
changes in SERS intensity implied the formation of a complex and its orientation on the silver
nanoparticles surface, however, the type of interactions between alkaloids and ribonucleotides
were not unambiguously indicated.

• Keywords: berberin; koloid; nanočestice srebra; papaverin; ribonukleotidi; SERS
• Keywords (english): berberine; colloid; papaverine; ribonucleotides; SERS; silver nanoparticles
• Language: croatian
• URN:NBN: urn:nbn:hr:217:882475
• Study programme: Title: Graduate university studies in chemistry; specializations in: Research programme; Course: Research programme; Study programme type: university; Study level: graduate; Academic / professional title: magistar/magistra kemije (magistar/magistra kemije)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Open access; Embargo expiration date: 2023-09-30
• Created on: 2022-10-24 16:29:27