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Publishing of the journal Agricultura is financially supported by Slovenian Research Agency.

Izdajanje revije Agricultura je finančno podprto s strani Javne agencije za raziskovalno dejavnost Republike Slovenije.


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The journal AGRICULTURA (A) publishes scientific works from the following fields: animal science, plant production, farm mechanisation, land management, agricultural economics, ecology, biotechnology, microbiology
ISSN 1581-5439
Janja Kristl, Metka Slekovec
pp. 23-26

An isocratic liquid chromatographic method for the determination of ascorbic acid (vitamin C) is described. The separation was performed on a C18 reversed-phase column with isocratic elution using phosphate buffer / methanol as a mobile phase. The photodiode array detector used was set at a wavelength of 245 nm. The limit of detection and determination was estimated at 0.23 mg/L and 0.46 mg/L per 50 μL injection. Ascorbic acid contents of freeze dried carrots, fresh squeezed lemon and grapefruit juices were analysed comparatively by liquid chromatography and by the AOAC official titrimetric method. Both methods gave similar results for each of the matrices analysed.

Keywords: ascorbic acid, liquid chromatography


Slovensko:

Določitev vitamina C s tekočinsko kromatografijo v sokovih limone, grenivke in v vzorcih posušenega korenja

V prispevku je predstavljena metoda za določanje askorbinske kisline (vitamina C) s tekočinsko kromatografijo. Ločitev je potekala na koloni z reverzno fazo C18 z izokratsko elucijo. Kot mobilno fazo smo uporabili fosfatni pufer in metanol. Intenziteto absorbirane svetlobe smo izmerili pri 245 nm. Pri volumnu injiciranja 50 µL je bila meja zaznave in določljivosti 0.23 mg/L in 0.46 mg/L. Vsebnost vitamina C v liofiliziranih vzorcih korenja, sveže stisnjenem soku limone in grenivke smo določili s tekočinsko kromatografijo in primerjalno s titracijo po AOAC metodi. Vsebnosti vitamina C, izmerjene po obeh metodah, so primerljive.


Ključne besede: askorbinska kislina / tekočinska kromatografija


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