Određivanje sadržaja teških metala u uzorcima kakaa primjenom TXRF-W, TXRF-Mo i EDXRF tehnike

master's thesis

• Title (english): Determination of heavy metal content in cocoa samples using TXRF-W, TXRF-Mo and EDXRF techniques
• Author: Igor Cvijanović
• Mentor: Jasna Jablan (mentor)
• Committee member: Jasna Jablan (predsjednik povjerenstva)
• Committee member: Suzana Inić (član povjerenstva)
• Committee member: Maja Bival Štefan (član povjerenstva)
• Granter: University of Zagreb; Faculty of Pharmacy and Biochemistry; (Department of analytical chemistry); Zagreb
• Defense date and country: 2024-03-11, Croatia
• Scientific / art field, discipline and subdiscipline: BIOMEDICINE AND HEALTHCARE; Pharmacy; Medical Biochemistry

Abstract

Plod stabla kakaovca jest zrno kakaa koje je ključni sastojak u proizvodnji kakao praha i čokolade. Zbog
velike zastupljenosti u ljudskoj prehrani, nužno je poznavanje sastava kakaa kako bi se osigurala kvaliteta i
sigurnost samih proizvoda. Glavni cilj ovog rada jest odrediti elementni sastav kakaa te usporediti rezultate
dobivene različitim analitičkim tehnikama (TXRF-W, TXRF-Mo, EDXRF). Uzorci su pripremljeni
mikrovalnom digestijom te u obliku peleta te je određeno prisustvo sljedećih elemenata: željezo, bakar,
cink, rubidij, stroncij, mangan, nikal i krom. Priprema uzorka u obliku peleta jeftinija je, manje zahtjevna i
ekološki prihvatljivija u odnosu na mikrovalnu digestiju. Analizom je utvrđeno da se rezultati dobiveni
različitim analitičkim tehnikama podudaraju (posebice između TXRF-Mo i EDXRF). Sve su se tehnike
pokazale kao vrlo korisne budući da omogućavaju identifikaciju i kvantifikaciju vrlo niskih koncentracija
elemenata prisutnih u uzorcima kakaa, s naglaskom na TXRF-Mo tehniku koja se pokazala kao
najosjetljivija.

Abstract (english)

The fruit of the cocoa tree is the cocoa bean which is a key ingredient in the production of cocoa powder
and chocolate. Since cocoa is widely used in the human diet, it is necessary to know the composition of
cocoa in order to ensure quality and safety of the products themselves. The main goal of this work is to
determine the elemental composition of cocoa and to compare the results obtained by different analytical
techniques (TXRF-W, TXRF-Mo, EDXRF). The samples were prepared by microwave digestion and in the
form of pellets and the presence of the following elements was determined: iron, copper, zinc, rubidium,
strontium, manganese, nickel and chromium. Sample preparation in the form of pellets is less-expensive,
simpler and more environmentally friendly than microwave digestion. The analysis showed that the results
obtained with the different analytical techniques were consistent (especially between TXRF-Mo and
EDXRF). All techniques have proven to be very effective, as they allow the identification and
quantification of very low concentrations of the elements present in cocoa samples, with the TXRF-Mo
technique which proving to be the most sensitive.

• Keywords: kakao; multielementna analiza; TXRF; EDXRF
• Keywords (english): cocoa; multielement analysis; TXRF; EDXRF
• Language: croatian
• URN:NBN: urn:nbn:hr:163:681634
• Study programme: Title: Medical biochemistry - integrated undergraduate and graduate - university study; Study programme type: university; Study level: integrated undergraduate and graduate; Academic / professional title: sveučilišni magistar medicinske biokemije i laboratorijske medicine (sveučilišni magistar medicinske biokemije i laboratorijske medicine)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Embargoed access; Embargo expiration date: 2026-03-11
• Created on: 2024-05-23 13:35:48