Optimizacija predobrade uzoraka ekstrakcijom čvrstom fazom za određivanje azatioprina, 6-tiogvanina i folne kiseline

master's thesis

• Title (english): Optimization of solid phase extraction as sample preparation technique for determination of azathioprine, 6-thioguanine and folic acid
• Author: Anica Rebrina
• Mentor: Ana Mornar Turk (mentor)
• Committee member: Ana Mornar Turk (predsjednik povjerenstva)
• Committee member: Biljana Nigović (član povjerenstva)
• Committee member: Maja Šegvić Klarić (član povjerenstva)
• Granter: University of Zagreb; Faculty of Pharmacy and Biochemistry; (Department of pharmaceutical analysis); Zagreb
• Defense date and country: 2018-05-14, Croatia
• Scientific / art field, discipline and subdiscipline: BIOMEDICINE AND HEALTHCARE; Pharmacy; Pharmacy

Abstract

Priprema uzoraka jedan je od glavnih koraka analize koji omogućuje odgovarajuću biološku interpretaciju. U biološkom uzorku su uz analit prisutne i brojne druge sastavnice koje mogu narušiti osjetljivost i selektivnost bioanalize, ali i oštetiti analitički instrument. Ekstrakcija čvrstom fazom jedna je od glavnih metoda pripreme uzoraka koja omogućuje uklanjanje interferencija u uzorku i ukoncentriravanje analita. Cilj ovog rada bio je ispitati učinkovitost različitih tipova sorbensa za ekstrakciju čvrstom fazom kao metodu pripreme uzorka za istovremeno određivanje azatioprina, 6-tiogvanina i folne kiseline u uzorku plazme. Azatioprin i 6-tiogvanin spadaju u skupinu imunosupresiva, jednu od glavnih skupina lijekova koji se koriste u liječenju upalnih bolesti crijeva. Kod ovih pacijenata postoji rizik od deficita folata, stoga je korisno uz lijekove istovremeno pratiti i razinu folata koja će omogućiti procjenu o potrebi za njihovom suplementacijom. Ispitivani modificirani silikagel (C8 i C18) i polimerni sorbens (HLB) nisu uspješno razdvojili interferencije od željenih analita stoga nisu pogodni za pripremu navedenog uzorka za daljnu analizu. Inovativni selektivni sorbens Phree Phospholipid Removal omogućuje istovremeno uklanjanje proteina i fosfolipida iz biološkog uzorka. Pripremom uzorka s ovim sorbensom uklanjaju se negativni učinci interferencija kao što su ionska supresija, nezadovoljavajuća osjetljivost i smanjen vijek trajanja kolone. Ovaj sorbens najprimjereniji je za pripremu navedenog uzorka za analizu. Analitički prinos za sve željene analite iznosio je približno 100%.

Abstract (english)

Sample preparation is one of the most important step in bioanalysis and it is crucial to ensure appropriate biological interpretation. In biological samples there are present, with the analyte, numerous other components which can reduce the sensitivity and selectivity of bioanalysis, as well as damage the analytical instrument. Solid phase extraction is one of the major sample preparation methods that allows removal of interferences and concentrating the target analytes. The aim of this study was to examine the efficiency of various types of sorbens for solid phase extraction as a sample preparation method for determination of azathioprine, 6-thioguanine and folic acid in plasma samples. Azathioprine and 6-thioguanine are immunosuppresants, one of the major group of medicines used in the treatment of inflammatory bowel disease. Pacients with IBD are at risk for folate deficiency, therefore it is usefull to monitor not only drugs but also the level of folate which shows the need for their supplementation. The following sorbents were tested: modified silica gel (C8 and C18), polymer sorbent (HLB) and innovative sorbent: Phree Phospholipid Removal. Examined modified silica gel and polymer sorbent have not successfully separated the interferences from the selected analytes. Therefore all of them are not suitable for the preparation of plasma samples. Innovative selective sorbent Phree Phospholipid Removal allows simultaneous removal of protein and phospholipids from a biological sample. The preparation of the sample with this sorbent removes the negative chromatographic effects of interferences such as ion suppression, reduced analyte sensitivity and decreased column life - time. This sorbent is most suitable for the preparation of plasma sample for analysis. Analytical recovery was near 100%.

• Keywords: ekstrakcija čvrstom fazom; bioanaliza; azatioprin; 6-tiogvanin; folna kiselina
• Keywords (english): solid phase extraction; bioanalysis; azathioprine; 6-thioguanine; folic acid
• Language: croatian
• URN:NBN: urn:nbn:hr:163:597038
• Study programme: Title: Pharmacy; Study programme type: university; Study level: integrated undergraduate and graduate; Academic / professional title: magistar/magistra farmacije (magistar/magistra farmacije)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Open access
• Created on: 2018-11-28 15:56:13