Development of the determination of melatonin in blueberries using LC-MS/MS

Melatonin (MLT) is an indolamine that presents a functional activity with a broad spectrum of action, highlighting its antioxidant, anti-inflammatory and immunomodulatory and anti-apoptotic capacity. It is a widely distributed hormone, found in most of the foods that make up a normal diet. There are many studies that analyze the MLT content in different foods and using different techniques. However, very little research has focused on analyzing MLT concentration in blueberries. Therefore, the aim of this study was the development of a method for the extraction and determination of MLT in blueberries (Vaccinium corymbosum), using liquid chromatography-tandem mass spectrometry (LC-MS/MS), which has been shown to be one of the most reliable and precise techniques for this type of analysis. It was determined that using methanol as an extraction solvent obtained greater efficiency than using acetonitrile. Likewise, the highest recovery percentages were achieved with the BOND ELUT PLEXA solid phase extraction (SPE) cartridges. With the optimization of the extraction process and subsequent analysis, it was determined that the blueberries used in this study had an MLT concentration of 0.173±0.028ng/g.