A simple quantitative method using TLC-image analysis to determine fructooligosaccharides (FOS) in food samples

Abstract

The thin-layer chromatography technique (TLC) is a simple and inexpensive analysis commonly used to identify qualitatively the presence of carbohydrates in food samples such as mono- di and oligosaccharides particularly. TLC assay could be improved using image processing software for the semiquantitative determination of this type of compound. In the present work, TLC-image analysis with Silica Gel 60 TLC plates was used for the semiquantitative determination of 6 standards of carbohydrates (glucose, fructose, sucrose, 1-kestose, nystose, and fructofuranosylnystose). Subsequently, the areas of the spots of each compound were determined by digitizing in a conventional office scanner. Then, the segmentation of the images is carried out using software for image processing. The calibration curves were plotted in the Excel software using the average of the areas of the pigmentations obtained in pixels. In this study, the technique of thin-layer chromatography was also used to quantitatively determine the presence of carbohydrates in food samples such as honey, garlic, and onion. Values of determination coefficient (R2) greater than 0.97 in all the calibration curves were obtained. This technique could be useful for detecting carbohydrates (monosaccharides, disaccharides, and oligosaccharides) in analytical assays and food samples without needing specialized analytical equipment. In this work, it was possible to determine the concentration of carbohydrates in samples of garlic and onion that showed the presence of prebiotic carbohydrates in addition to sucrose, glucose, and fructose.

Forensic discrimination of blue fountain pen inks based on dielectric constant property

“…Recent developments in digital image technology allow for a more precise quantitative analysis of the TLC plate based on the image and several studies have been conducted on quantitative determination employing TLC-IA, where a flatbed scanner is utilized to capture the image of the colored analyte spots [20]. Due to being cost-effective and straightforward analysis method TLC is a frequently employed for the qualitative identification of sample content [21]. In this study TLC was effectively used to differentiate between the colored components of inks and RGB (stands for red, green, and blue) [22] analysis.…”