TY - JOUR
T1 - Stability of Lisdexamfetamine in Sampled Whole Blood – Implications of Sampling Tube Additives and Storage Temperature for Interpretation of Impairment
AU - Sørensen, Lambert Kristiansen
AU - Andreasen, Mette Findal
AU - Jornil, Jakob Ross
AU - Andersen, Charlotte Uggerhøj
AU - Hasselstrøm, Jørgen Bo
PY - 2023
Y1 - 2023
N2 - Lisdexamfetamine (LDX) is a prodrug that is enzymatically converted into dextroamphetamine (d-AMP), a central nervous system stimulant. The stability of LDX in sampled whole blood is an important issue that may be crucial in the assessment of impaired driving caused by d-AMP. This study investigated the stability of LDX in whole blood collected in two different tubes containing a fluoride oxalate (FX) mixture and a fluoride citrate (FC) mixture. Without additives, LDX was unstable. LDX was also unstable in FX blood stored at ambient temperature or 4°C. After 3 days of storage at ambient temperature, an initial LDX concentration of 47 ± 1 ng/g (mean ± SD) was no longer detectable in the samples (n = 3). Instead, 19 ± 0.6 ng/g d-AMP was formed. The stability was improved at 4°C. After 7 days of storage at 4°C, 88 ± 5% of an initial LDX concentration of 50 ± 0.4 ng/g was recovered and 3.8 ± 0.3 ng/g d-AMP was formed. The stability of LDX was greater in FC blood than in FX blood; 79 ± 10% and 93 ± 4% of initial LDX concentrations of 48 ± 2 and 51 ± 0.5 ng/g were recovered from FC blood after 7 days of storage at ambient temperature and 4°C, respectively, and the corresponding formation of d-AMP was 5.8 ± 0.6 and 0.5 ± 0.3 ng/g, respectively. When FX and FC blood were stored at -20°C or -80°C, no detectable degradation of LDX or formation of d-AMP was observed after 3 weeks of storage.
AB - Lisdexamfetamine (LDX) is a prodrug that is enzymatically converted into dextroamphetamine (d-AMP), a central nervous system stimulant. The stability of LDX in sampled whole blood is an important issue that may be crucial in the assessment of impaired driving caused by d-AMP. This study investigated the stability of LDX in whole blood collected in two different tubes containing a fluoride oxalate (FX) mixture and a fluoride citrate (FC) mixture. Without additives, LDX was unstable. LDX was also unstable in FX blood stored at ambient temperature or 4°C. After 3 days of storage at ambient temperature, an initial LDX concentration of 47 ± 1 ng/g (mean ± SD) was no longer detectable in the samples (n = 3). Instead, 19 ± 0.6 ng/g d-AMP was formed. The stability was improved at 4°C. After 7 days of storage at 4°C, 88 ± 5% of an initial LDX concentration of 50 ± 0.4 ng/g was recovered and 3.8 ± 0.3 ng/g d-AMP was formed. The stability of LDX was greater in FC blood than in FX blood; 79 ± 10% and 93 ± 4% of initial LDX concentrations of 48 ± 2 and 51 ± 0.5 ng/g were recovered from FC blood after 7 days of storage at ambient temperature and 4°C, respectively, and the corresponding formation of d-AMP was 5.8 ± 0.6 and 0.5 ± 0.3 ng/g, respectively. When FX and FC blood were stored at -20°C or -80°C, no detectable degradation of LDX or formation of d-AMP was observed after 3 weeks of storage.
KW - Central Nervous System Stimulants
KW - Dextroamphetamine
KW - Double-Blind Method
KW - Fluorides
KW - Lisdexamfetamine Dimesylate
KW - Temperature
KW - Treatment Outcome
UR - http://www.scopus.com/inward/record.url?scp=85144699488&partnerID=8YFLogxK
U2 - 10.1093/jat/bkac025
DO - 10.1093/jat/bkac025
M3 - Journal article
C2 - 35511961
SN - 0146-4760
VL - 47
SP - 33
EP - 42
JO - Journal of Analytical Toxicology
JF - Journal of Analytical Toxicology
IS - 1
ER -