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Background and Aim: The increase of the carbohydrate-deficient transferrin (CDT) as results of an heavy intake of alcohol for at least two weeks, is a well-known biochemical modification since the middle '70s. Notwithstanding the first commercial kit for the diagnosis of chronic alcohol abuse based on this biomarker was commercially accessible already thirty years ago, only expensive analytical methods are currently available for its determination. The present paper shows a new approach intrinsically sensitive and specific, based on a specific derivatization of transferrin, and not requiring sophisticated instrumentation., Methods: The proposed procedure is based on a selective chelation of terbium (III) by transferrin followed by detection using an characteristic Fluorescence Resonance Transfer Energy (FRET) phenomenon (ex 298 nm - em 550 nm)., Results: The proposed procedure showed a limit of detection of 2.5 pmol/mL and a reproducibility intra-day and inter-days <15% and 20%, respectively. The results obtained analyzing 40 serum samples using the developed method, were compared with those obtained with HPLC-Vis and an R 2  = 0.8854 was found., Conclusions: Considering its main features (low-cost, ease of operation, minimum need of instrumentation) the present method is suitable for application in screening contexts and in non-strictly regulated environments (e.g. clinical diagnosis) as well as in developing countries or remote areas., (Copyright © 2019 Elsevier B.V. All rights reserved.)

Background and Aim: CDT is a collective biomarker including asialo- and disialo-Tf, but researchers have generally focused attention on disialo-Tf, because of its easier detectability, since asialo-Tf is typically not detectable by the current methods in abstinent individuals, social drinkers and in many alcohol abusers with moderate CDT increases. In the search of a confirmation marker of alcohol-related CDT increases, the detectability of asialo-Tf was re-evaluated comparatively by using CE vs. HPLC., Methods: 468 serum samples compulsorily drawn in a forensic/administrative context were analyzed by CE and HPLC to compare their sensitivity towards asialo-Tf., Results: CE allowed the identification of asialo-Tf in 108 out of 165 CDT "positive" cases, based on disialo-Tf measurement (cut-off 1.8%). HPLC showed a detectable asialo-Tf peak only in 2 cases. In addition, in some cases of disputed CDT increases, the quasi-absence of this Tf component in front of an important increase of disialo-Tf allowed the ruling out of a diagnosis of alcohol abuse, in agreement with all other clinical and laboratory data., Conclusions: The present work shows a superior performance of CE vs. HPLC for the determination of asialo-Tf and the importance of this CDT component to avoid misinterpretation of non-alcohol related CDT increases., (Copyright © 2018 Elsevier B.V. All rights reserved.)

Background and Aim: The non-glycosylated glycoform of transferrin (Tf), known as asialo-Tf, was not selected (in favor of disialo-Tf) as the measurand for the standardization of carbohydrate deficient transferrin (CDT) determination because of a lower diagnostic sensitivity provided with the currently available analytical procedures for sera. However, asialo-Tf could provide an additional value to disialo-Tf in the CDT analysis employed in forensic toxicology contexts. The present work aimed at developing an easy sample preparation based on PEG precipitation in order to improve the detectability of asialo-Tf in capillary electrophoresis (CE)., Methods: Equal volumes (35 μL) of serum and of 30% PEG-8000 were mixed and briefly vortexed. After centrifugation, the supernatant was iron saturated with a ferric solution (1:1, v/v). The mixture was analyzed in CE for asialo-Tf and disialo-Tf determination., Results: PEG-8000 precipitation allowed the improvement of the baseline in the electropherograms in terms of interferences reduction particularly in the asialo-Tf migration region. The detection of asialo-Tf was possible in 89% of samples with disialo-Tf above the cut-off limit, whereas only 16% of them showed asialo-Tf by employing the traditional sample preteatment., Conclusions: Asialo-Tf represents an additional value to disialo-Tf as a biomarker of alcohol abuse in forensic toxicology., (Copyright © 2018. Published by Elsevier B.V.)