Validation of Dried Blood Spot Cards to Determine Apple Phenolic Metabolites in Human Blood and Plasma After an Acute Intake of Red‐Fleshed Apple Snack

Abstract

Scope The application of dried blood spot (DBS) cards for the study in human blood of dietary polyphenol bioavailability has been poorly studied. Methods and results An analytical method based on blood sampling with DBS cards combined with LC–MS/MS has been developed and validated. To test the method validation, the phenolic metabolites are determined in human blood and plasma obtained after an acute intake of a red‐fleshed apple snack in ten volunteers. Capillary blood by finger prick is compared to venous blood by venipuncture and whole blood is also compared to their corresponding venous plasma samples. Moreover, the venous plasma results using DBS cards are compared to those obtained by microElution solid phase extraction (µSPE). The main phenolic metabolites detected in blood and plasma samples are phloretin glucuronide, dihydroxyphenylpropionic acid sulphate, (methyl) catechol sulphate, catechol glucuronide, and hydroxyphenyl‐γ‐valerolactone glucuronide. No significant differences are observed between capillary blood, venous blood, and plasma samples using DBS, and neither between plasma samples analyzed by DBS or µSPE. Conclusions Finger‐prick blood sampling based on DBS appears to be a suitable alternative to the classic invasive venipuncture for the determination of circulating phenolic metabolites in nutritional postprandial studies.

Metabolic Fate and Cardiometabolic Effects of Phenolic Compounds from Red‐Fleshed Apple in Hypercholesterolemic Rats: A Comparative Study with Common White‐Fleshed Apple. The AppleCOR Study

“…[35] The detected dihydrochalcone metabolites were also reported by other studies in biological samples after the intake of cider, [36] and red-fleshed apple snack in humans. [21,23] To our knowledge, the colonic metabolism of dihydrochalcones has been scarcely studied, and the obtained results were in agreement with previous studies. [26][27][28] When studying the metabolic fate of PC after apple and aronia supplementation, a gender effect was also reported.…”

“…The UPLC-MS/MS conditions were the same used in the previous studies. [16,21,23] Tandem mass spectrometry analyses were carried out on a triple quadrupole detector mass spectrometer (Waters, Milford, MA, USA) equipped with a Z-spray electrospray interface.…”

Phenol Biological Metabolites as Food Intake Biomarkers, a Pending Signature for a Complete Understanding of the Beneficial Effects of the Mediterranean Diet

“…Based on all the studies analysed, the phloretin biological metabolites (glucuronide and sulphate conjugates), analyzed preferably in urine, could be proposed as biomarkers of apple intake based on the specificity of their precursor phloridzin as phenolic compound characteristic for apples. Regarding phenol colonic metabolites in plasma during postprandial period, especially those late time points (12 h after food intake), these are normally missing in studies when blood sampling is done by venepuncture because blood sampling is usually only possible between 0 and 6–8 h. In a recent study by Yuste et al [ 54 ], a method based on the use of Dried Blood Spot (DBS) cards (blood sampling) combined with liquid chromatography coupled to mass spectrometry (UPLC-MS/MS) was optimised and applied for determining phenolic metabolites in human blood and plasma samples after the acute intake of an apple snack. Similar to other studies, the phloretin glucuronide detected in blood and plasma samples was selected as a biomarker of apple intake.…”

Biomarkers of Nutrition and Health: New Tools for New Approaches

“…For certain applications, the blood from a finger or heel prick deposited and absorbed on paper, the so-called ‘dried blood spot’ technique, can be used for screening, for example, genetic screening of infants for phenylketonuria or to analyse certain hormonal or metabolites, such as fatty acid analysis [76]. Due to rapid technological developments, dried blood spot approaches are currently being developed to assess nutrient exposure [77], to identify nutrient-exposure associated risk markers [78] and to quantify markers for nutrition-related metabolic status [79], as well as disease risk markers [80].…”