Validation of the quantification of phosphatidylethanol 16:0/18:1 concentrations in TASSO‐M20 devices

Abstract

AbstractBackgroundPhosphatidylethanol 16:0/18:1 (PEth), found in whole blood, is a biomarker for alcohol consumption with high sensitivity, specificity, and a long detection window. The TASSO‐M20 device is used to self‐collect capillary blood from the upper arm and has advantages over finger stick methods. The purpose of this study was to (1) validate PEth measurement using the TASSO‐M20 device, (2) describe the TASSO‐M20 for blood self‐collection during a virtual intervention, and (3) characterize PEth, urinary ethyl glucuronide (uEtG) and self‐reported alcohol in a single participant over time.MethodsPEth levels in blood samples dried on TASSO‐M20 plugs were compared to those in (1) liquid whole blood (N = 14) and (2) dried blood spot cards (DBS; N = 23). Additionally, the self‐reported drinking, positive or negative uEtG results (dip card cutoff ≥300 ng/mL), and observed self‐collection of blood with TASSO‐M20 devices for PEth levels were obtained over time during virtual interviews of a single contingency management participant. High‐performance liquid chromatography with tandem mass spectrometry detection was used to measure PEth levels for both preparations.ResultsPEth concentrations from dried blood on TASSO‐M20 plugs and liquid whole blood were correlated (0 to 1700 ng/mL; N = 14; r2 = 0.988; slope = 0.951) and in a subgroup of samples with lower concentrations (N = 7; 0 to 200 ng/mL; r2 = 0.944, slope = 0.816). PEth concentrations from dried blood on TASSO‐M20 plugs and DBS were correlated (0 to 2200 ng/mL; N = 23; r2 = 0.927; slope = 0.667) and in a subgroup of samples with lower concentrations (N = 16; 0 to 180 ng/mL; r2 = 0.978, slope = 0.749). Results of the contingency management participant indicate that changes in PEth levels (TASSO‐M20) and uEtG concentrations were consistent with each other and with changes in self‐reported alcohol use.ConclusionsOur data support the utility, accuracy, and feasibility of using the TASSO‐M20 device for blood self‐collection during a virtual study. The TASSO‐M20 device had multiple advantages over the typical finger stick method, including consistent blood collection, participant acceptability, and less discomfort as indicated by acceptability interviews.