Spektrofotometrično določanje vitaminov v prehranskih dopolnilih

Ahlin, Taja (author), Prosen, Helena (mentor)

Za določitev vitaminov C, B2 in B6 v prehranskih dopolnilih sem uporabila spektrofotometrično metodo. Pri vseh vitaminih je določevanje temeljilo na obarvanju ali pa spremembi obarvanja vzorca zaradi kemijske reakcije ali pa naravnega obarvanja raztopine vitamina. V delu so podani rezultati preizkušanja metode za vsak vitamin posebej. V prvi fazi sem pripravila umeritvene krivulje s pomočjo standardnih raztopin. Za vitamin C sem izdelala umeritveno krivuljo v območju od 5-100 mg/L, za vitamin B2 v območju 5-30 mg/L in za vitamin B6 v območju 10-50 mg/L. Izkazalo se je, da se spektrofotometrične metode za vse tri vitamine na realnih vzorcih ne obnesejo dobro, zaradi kompleksne matrice analiziranih vzorcev. Ti namreč vsebujejo veliko polnil in dodanih barvil, ki motijo meritve.

• Language: Slovenian
• Keywords: spektrofotometrija, vitamin C, vitamin B2, vitamin B6, prehranska dopolnila
• Work type: Bachelor thesis/paper
• Typology: 2.11 - Undergraduate Thesis
• Organization: FKKT - Faculty of Chemistry and Chemical Technology
• Year: 2021
• PID: 20.500.12556/RUL-129712
• COBISS.SI-ID: 79224579
• Publication date in RUL: 07.09.2021

Secondary language

• Language: English
• Title: Spectrophotometric determination of vitamins in food supplements

Abstract

I used a spectrophotometric method to determine vitamins C, B2 and B6 in dietary supplements. For all vitamins, the determination was based on the color or change of color of the sample due to a chemical reaction or the natural color of the vitamin solution. The paper presents the results of the method evaluation for each vitamin separately. In the first phase, I prepared calibration curves using standard solutions. For vitamin C, I constructed a calibration curve in the range of 5–100 mg/L, for vitamin B2 in the range of 5–30 mg/L, and for vitamin B6 in the range of 10–50 mg/L. It turned out that the spectrophotometric methods for all three vitamins did not work well on real samples, due to the complex matrix of the analyzed samples. These contain a lot of fillers and added dyes, which interfere with the measurements.

• Keywords: spectrophotometry, vitamin C, vitamin B2, vitamin B6, dietary supplements