DETERMINATION OF METHYLXANTHINES IN CHOCOLATE SAMPLES

Ciljevi istraživanja: Kvalitativno dokazati prisutnost metilksantina u uzorcima čokolade i biološkim uzorcima mokraće primjenom GC-MS metode. Utvrditi koja je metoda, SPE ili LLE metoda, prikladnija. Usporediti rezultate analize dobivene nakon pripreme bioloških uzoraka LLE metodom kod različitih ispitanika. Materijali i metode: Korišteni su uzorci 11 čokolada (3 tamne i 8 mliječnih čokolada) te biološki uzorci urina tri ispitanika. Uzorci čokolada pripremljeni su SPE metodom, dok su Dorina čokolada za kuhanje te biološki uzorci pripremljeni LLE metodom. Svi uzorci su analizirani na GC-MS uređaju. Rezultati: U 10 uzoraka čokolade te u svim biološkim uzorcima detektirani su teobromin i kofein. Uzorci pripremljeni za analizu LLE metodom dali su bolji signal od uzoraka pripremljenih za analizu SPE metodom. Postoje razlike u signalima metilksantina kod različitih ispitanika. Zaključci: Analizom provedenom GC-MS tehnikom uspješno je kvalitativno dokazana prisutnost metilksantina u uzorcima 3 crne i 7 mliječnih čokolada te u biološkim uzorcima mokraće. LLE metoda pokazala je veću učinkovitost u pripremi uzoraka za analizu od SPE metode. Analizom provedenom GC-MS tehnikom uspoređeni su rezultati dobiveni nakon pripreme bioloških uzoraka ekstrakcijom tekuće-tekuće kod 3 različita ispitanika. Utvrđeno je kako postoje razlike u rezultatima te je potrebno provesti daljnja ispitivanja usporedbe bioloških uzoraka.Objectives: Qualitatively demonstrate the presence of methylxanthines in chocolate samples and biological samples of urine using the GC-MS method. Determine what method, SPE or LLE method, is more appropriate. Compare the results of the analysis obtained after the preparation of biological samples by the LLE method in different subjects. Materials and methods: Samples of 11 chocolates and biological samples of urine were used. Chocolate samples were prepared by the SPE method, while Dorina Chocolate for cooking and biological samples were prepared by the LLE method. All samples were analyzed with GC-MS method. Results: In 10 chocolate samples and in all biological samples, theobromine and caffeine were detected. Samples prepared for the LLE method analysis provided a better signal from samples prepared for SPE analysis. There are differences in the methylsantine signals in different subjects. Conclusion: The presence of methylxanthines in 3 black and 7 milk chocolate samples and in biological samples has been successfully demonstrated. LLE method showed greater efficiency in preparation of samples for analysis. It has been found that there are differences in results obtained after the preparation of biological samples by liquid-liquid extraction in 3 different subjects and a further study of the comparison of biological samples has to be carried out