Miniaturizovaný elektrochemický detektor pro kapilární \nl{}monolitické kolony

Bc. Zuzana Holíková

Master's thesis

Miniaturized electrochemical detector for capillary monolithic columns

Abstract:

Prace se zabyva studiem vlivu geometrickeho uspo.adani, zp.sobu zapojeni jednotlivych elektrod a rychlosti pr.toku mobilni faze na proudovou odezvu dopaminu m..enou pomoci miniaturizovaneho .ty.elektrodoveho detektoru. Tetrody se .pi.atym a rovnym hrotem byly zabudovany do kapilar o pr.m.rech 320 ?Ęm a 530 ?Ęm. Detekce dopaminu byla provedena biamperometricky ve sm.si acetonitril:fosfatovy pufr (1:1) a nasledn. v samotnem fosfatovem pufru. Nejvy..ich proud. bylo dosa.eno p.i pou.iti tetrody se .pi.atym hrotem v kapilarni kolon. o pr.m.ru 530 ?Ęm p.i spojeni elektrod 2+2 a pr.toku 5 ?Ęl/min 0,1 M fosfatoveho pufru. Dale byla vyzkou.ena mo.nost amperometricke detekce katecholamin. ve dvouelektrodovem uspo.adani s vyu.itim platinove pracovni a st.ibrne pseudoreferentni elektrody. K tomuto u.elu byly dv. mikroelektrody tetrody modifikovany st.ibrem elektrodepozici.

Abstract:

The thesis deals with the study of influence of geometrical arrangement, interconnection of electrodes, and the flow rate of mobile phase on the dopamine current response measured at miniaturized four-electrode detector. Tetrodes with conical or plane tip were embedded into capillaries with diameters of 320 microns and 530 microns. Detection of dopamine was performed in acetonitrile:phosphate buffer (1:1) and phosphate buffer using biamperometry. Highest currents were obtained at tetrode with conical tip placed in530 ěm diameter capillary, interconnection of electrodes 2+2, and flow rate of 5 ěl/min in phosphate buffer. Furthermore, the possibility of amperometric detection of catecholamines using two-electrode arrangement with platinum working and silver pseudoreference electrodes was tested. For this purpose, two microelectrodes of tetrode were modified by the electrodeposition of silver.

Keywords

Elektrochemická detekce, tetrody, katecholaminy, dopamin, elektrodepozice

Language used: Czech

Date on which the thesis was submitted / produced: 27. 5. 2015

Thesis defence

• Date of defence: 1. 6. 2015
• Supervisor: Ing. Radovan Metelka, Ph.D.

University of Pardubice

Faculty of Chemical Technology

Master programme / field:
Chemistry / Analytical Chemistry