Stanovení vybraných mastných kyselin v mateřském mléce - zameření na přípravu vzorku před analýzou

Abstract

The mother's milk is also known as human milk or breastmilk (HBM) that is the main significant form of nutrition for infants, especially premature newborns since it is essential for their development of the immune system, brain development, and being the source of energy due to HBM breaking down into triglycerides (TG) and releasing fatty acids (FAs). Therefore, this thesis is to optimize the sample preparation procedures for detecting the selected fatty acids in the mother's milk fat composition using the micro-sample technique based on dried milk spot (DMS) in order to enhance the fatty acid analysis by using smaller sample volumes, detecting and quantifying FAs efficiently.<br>This study works with donated HBM prepared in form of DMS which initially went through lipid extraction from the matrix by testing various types of solvent extraction and other related parameters, including state of extraction, time interval, approach of extraction if using DMS or liquid milk droplet of HBM (LMD), then is followed by derivatization as it is vital step for detecting organic compounds using gas chromatography coupled with a flame ionization detector (GC-FID) and then the prepared fatty acid methyl ester (FAME) were analyzed by GC-FID for its high selectivity and sensitivity. Finally, the results presented by peak areas corresponding to individual FA were converted into concentration and compared to select the potential sample preparation parameters for the determination of selected fatty acids. <br>This thesis has revealed that lipid extraction solvent Methanol/Toluene in ratio of 1:4 showed efficiency in extracting monounsaturated fatty acid (MUFA) and polyunsaturated fatty acid (PUFA) under using ultrasonic water bath (UWB) within 30 mins of using DMS with sample volume of 25 ?l. Therefore, this thesis contributes to the significance of analytical research by providing a practical sample preparation for profiling selected FA composition efficiently and sufficiently.