RESUMEN
Anabolic androgenic steroids are widely abused substances in sports doping. Their detection present limitations regarding the use of soft ion sources such as electrospray or atmospheric pressure chemical ionization by liquid chromatography-tandem mass spectrometry. In the current study, a novel derivatization method was developed for the ionization enhancement of selected anabolic androgenic steroids. The proposed method aims at the introduction of an easily ionizable moiety into the steroid molecule by converting the hydroxyl groups into imidazole carbamates using 1,1'-carbonyldiimidazole as derivatization reagent. The proposed method was applied to water and urine samples spiked with exogenous anabolic androgenic steroids in various concentration levels. Steroid imidazole carbamate derivatives have shown intensive [M+H]+ signals under electrospray ionization and common fragmentation patterns in tandem mass spectrometry mode with [M-CO2 +H]+ and [M-ΙmCO2 +H]+ as major ions with low collision energy. The obtained results showed that the majority of steroids were detectable at concentrations equal or lower to their minimum required performance level according to the World Anti-Doping Agency technical document. The proposed method is sensitive with a preparation procedure that could be easily applied to the analysis of doping control samples.
Asunto(s)
Andrógenos/orina , Imidazoles/química , Esteroides/orina , Detección de Abuso de Sustancias , Cromatografía Liquida , Doping en los Deportes , Humanos , Conformación Molecular , Estereoisomerismo , Espectrometría de Masas en TándemRESUMEN
Malnutrition is a prevalent issue in hospitals, nursing homes and the community setting. Nutritional products can be used by dietitians to supplement people's diet by adding energy, macronutrients and other constituents. The aim of the present work was (i) to create a database of nutritional products with information on their energy and macronutrient content, (ii) to estimate the food exchanges of each product and assist in diet plan development for malnourished persons and (iii) to provide a tool for calculation of food exchanges of newly developed products not included in the database. We searched the web for nutritional supplements, and an electronic database with 461 products was generated with data regarding the contained energy and macronutrients of each entry. The following companies were included: Abbott Nutrition, Nestle Nutrition, Nutricia North America, Nutricia Global, Nutricia Europe & Middle East, Axcan Pharma Inc., Kate Farms, Global Health, High Protein, NutriMedical BV, Hormel Health Labs, Hormel Health Labs/Diamond Crystal Brands, Lyons Magnus, Mead Johnson, Medical Nutrition USA Inc., Medtrition, Nutritional Designs Inc., Nutrisens, Humana (Germany), and Vitaflo USA. The created database facilitates product comparisons and categorization into several groups according to energy and protein content. In addition, a tool was created to determine food exchanges for each supplement per serving and/or food exchanges for newly developed products by simply inserting their macronutrient content. The developed tool can facilitate dietitians in comparing products and incorporating them into diet plans, if needed. Such tools may thus serve clinical practice, may be used in dietary or other smart applications and can familiarize dietitians with the digital epoch.