Utjecaj površinsko aktivnih organskih tvari na elektrokemijsko određivanje kapaciteta kompleksiranja bakra u morskoj vodi

master's thesis

• Title (english): Influence of surface active organic substances on electrochemical determination of copper complexing capacity in seawater
• Author: Martina Matanović
• Mentor: Slađana Strmečki Kos (mentor)
• Committee member: Nives Galić (predsjednik povjerenstva)
• Committee member: Željka Soldin (član povjerenstva)
• Committee member: Nikola Cindro (član povjerenstva)
• Committee member: Iva Juranović Cindrić (član povjerenstva)
• Granter: University of Zagreb; Faculty of Science; (Department of Chemistry); Zagreb
• Defense date and country: 2022-09-26, Croatia
• Scientific / art field, discipline and subdiscipline: NATURAL SCIENCES; Chemistry

Abstract

Kapacitet kompleksiranja bakra (KKCu) predstavlja sposobnost organskih molekula u
prirodnim vodama da “vežu” određenu koncentraciju Cu2+
-iona u stabilne komplekse čime se
regulira njihova biodostupnost. Metodom diferencijalo pulsne voltametrije anodnog otapanja
uz viseću živinu kap kao radnu elektrodu definirani su uvjeti mjerenja (desorpcijski potencijal,
Ed = −1,4 V i dodatak 1 mg dm−3 T-X-100) pri kojima je minimalan utjecaj adsorpcije organskih
površinsko aktivnih tvari (BSA, kitozan, karagenan, alginat, dekstran, fulvična kiselina) na
detekciju Cu2+
-iona. Optimalni uvjeti primijenjeni su za određivanje parametara KKCu u
uzorcima postaje SJ101 (0 m i dno) uzorkovani u proljeće-ljeto 2017. godine u sjevernom
Jadranu: određena su dva razreda liganada (12,0 − 71,5)x10−9 mol dm−3
i pripadajuće uvjetne
konstanta stabilnosti (log K´ = 8,42 − 11,17). Koncentracije liganada su bile više u površinskom
sloju tijekom ljetnih mjeseci kada je izraženija fitoplanktonska aktivnost.

Abstract (english)

Copper complexing capacity (KKCu) represents the ability of organic molecules in natural
waters to „bind“ a certain concentration of Cu2+
-ions in stable complexes, regulating their
bioavailability. Using the differential pulse voltammetry method the measurement conditions
were defined (desorption potential, Ed = −1.4 V, addition of 1 mg dm−3 T-X-100) under which
the adsorption interference of organic surface-active substances (BSA, chitosan, carrageenan,
alginate, dextran, fulvic acid) on the working electrode (mercury drop) is minimal for the
detection of Cu2+
-ions. The optimal conditions were applied to determine the KKCu parameters
in the samples from station SJ101 (0 m and bottom) sampled in the northern Adriatic Sea in
spring/summer 2017: two classes of ligands were determined (12.0 − 71.5)x10−9 mol dm−3
and
the corresponding conditional stability constants (log K´ = 8.42 − 11.17). The concentrations of
ligands were higher in the surface layer during the summer months due to more pronounced
phytoplankton activity.

• Keywords: kapacitet kompleksiranja bakra; površinsko aktivne tvari; voltametrija; uzorci morske vode; sjeverni Jadran
• Keywords (english): copper complexing capacity; surface-active compounds; voltammetry; seawater samples; northern Adriatic
• Language: croatian
• URN:NBN: urn:nbn:hr:217:346193
• Project: Number: IP-2018-01-3105; Title: Biokemijski odgovori površinskog sloja oligotrofnog područja Jadranskog mora na atmosfersko taloženje; Acronym: BiREADI; Leader: Sanja Frka Milosavljević; Jurisdiction: Croatia; Funder: HRZZ; Funding stream: IP
• 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: Embargoed access; Embargo expiration date: 2024-09-26
• Created on: 2022-10-20 14:29:54