Stabilnost in kontrolirano sproščanje vitamina D v simulacijskih raztopinah

magistrsko delo

Danijel Lavrič (Author), Petra Kotnik (Mentor), Maša Knez Hrnčič (Co-mentor)

Abstract

Stabilnost in topnost vitamina D v raztopinah sta pomembni lastnosti, ki jih je potrebno dobro poznati pri pripravi različnih formulacij prehranskih dopolnil ali zdravil. Znano je, da je vitamin D slabo topen v vodnih raztopinah, prav tako pa vemo, da je občutljiv na pH, svetlobo, temperaturo ter hitro oksidira. Namen našega magistrskega dela je bil predvsem določiti stabilnost in topnost vitamina D v različnih simulacijskih raztopinah. S pomočjo stresnih testov smo preverjali vpliv temperature in pH na razpad vitamina D v raztopini. Analize dobljenih vzorcev smo opravili na napravi LC-MS in ugotovili, da razpad sicer najhitreje poteka pri temperaturi 60°C, vendar temperatura pri razpadanju, ni odločilni faktor. Bolj pomembna je namreč izbira raztopine oz. njen pH, saj so rezultati analiz pokazali, da se razpad v HCl začne zelo hitro, medtem ko prve razpadne produkte v primeru NaOH in H2O2, opazimo šele po 4 urah. Nizek pH in visoka temperatura torej najbolj negativno vplivata na stabilnost vitamina D v raztopinah. S pomočjo testov topnosti smo ugotovili, da v vodi dosežemo samo 1 % deleža topnosti vitamina D, kot se ga raztopi v MeOH. V raztopini 0,1 % SDS ta delež sicer znaša 7 %, vendar je tudi to dokaj malo. Z primerjavo topnosti različnih formulacij smo potrdili, da se tableta in kapsula v SDS v celoti raztopita, pri čemer pa je vitamin D v obliki kapsule bolj zaščiten pred vplivi okolice, kot v tableti. V zadnjem delu magistrskega dela smo opravili še teste v simuliranih gastrointestinalnih pogojih. Simulirane raztopine sline in želodčnih sokov smo pripravili s pomočjo encimov α-amilaze (slina) in pepsina (želodec). Rezultati analiz so pokazali, da α-amilaza odločilno vpliva na topnost vitamina D v ustih, medtem ko pepsin v želodcu na topnost nima vpliva. Najvišje koncentracije raztopljenega vitamina D smo dosegli v simuliranih oralnih pogojih, medtem ko je v kislih želodčnih koncentracija začela upadati oz. je vitamin D začel razpadati. Zaradi tega bi bilo smiselno narediti primerjavo uporabe ustnih pršil z klasičnimi trdnimi formulacijami, ki vsebujejo vitamin D. Sicer pa pri nadaljnjih raziskavah na tem področju, priporočamo uporabo manjših volumnov in nižjih koncentracij α-amilaze, ki naj bo pripravljena v vodni raztopini.

Keywords

stabilnost vitamina D;topnost vitamina D;gastrointestinalni testi;pepsin;α-amilaza;magistrske naloge;

Data

Language:	Slovenian
Year of publishing:	2022
Typology:	2.09 - Master's Thesis
Organization:	UM FKKT - Faculty of Chemistry and Chemical Engineering
Publisher:	[D. Lavrič]
UDC:	604.4:577.16(043.2)
COBISS:	99477763
Views:	83
Downloads:	11
Average score:	0 (0 votes)
Metadata:

Other data

Secondary language:	English
Secondary title:	Stability and controlled release of vitamin D in simulation solutions
Secondary abstract:	Stability and solubility of vitamin D in solutions are properties that play very important role in preparation of different food supplements or drugs. It’s known that vitamin D has a very poor solubility in water solutions. Studies suggest that various factors such as temperature, pH, light and oxygen have big influence on stability of vitamin D in solutions. Therefore the main goal of our studies was to determine stability in solubility of vitamin D in different simulation solutions. Stress tests were carried out to determine the effect of temperature and pH on stability of vitamin D. Analysis were preformed with LC-MS method. We determined, that higher temperature had caused the fastest degradation of vitamin D in solution, but we have also noticed that it is not the most important factor regarding the speed of degradation. Results shoved that pH had far more bigger impact on the stability of vitamin D than temperature. Mass spectra shoved, that degradation of vitamin D occurred very fast when using HCl, meanwhile when we used NaOH and H2O2, degradation products started to form after 4 hours. With that we determined that vitamin D is least stable in low pH and at high temperatures. Solubility tests were preformed in order to determine how much vitamin D can be dissolved in our simulated solutions in comparison to solubility of it in MeOH. Results shoved that we could dissolve only 1% of vitamin D in water, compared to MeOH and the most we could dissolve was 7 % in SDS solution. For the effect of formulation of vitamin D we carried out solubility tests of tablet and capsule. As expected both formulation dissolved completely in solution and the only difference was that tablet was more prone to the effect of matrix, which was also expected. Last part of our studies was reserved for gastrointestinal tests, which simulated oral and gastro conditions. α-amylase and pepsin were used to prepare the simulated solutions of saliva and gastric juices. Results of analysis shoved that α-amylase has the most important role in the solubility of vitamin D, meanwhile pepsin doesn't effect solubility. The highest measured concentration of dissolved vitamin D were found in simulated saliva solution, while in gastric conditions vitamin D started to disintegrate. That means its possible that mouth spray solutions with vitamin D could have better effect than other solid oral doses. For the determination of that hypothesis it would be necessary to do more studies. However we can recommend the use of smaller volumes and lower concentrations of α-amylase which should be prepared in aqueous solution for further studies.
Secondary keywords:	stability of vitamin D;solubility of vitamin D;gastrointestinal tests;pepsin;α-amylase;
Type (COBISS):	Master's thesis/paper
Thesis comment:	Univ. v Mariboru, Fak. za kemijo in kemijsko tehnologijo
Pages:	1 spletni vir (1 datoteka PDF (63 f.))
ID:	14462326