The Effectiveness of Temperature Versus Aprotinin in Maintaining the Preanalytical Stability of Adrenocorticotrophin.
OBJECTIVE
To investigate the effect of temperature and protease inhibitor on adrenocorticotrophin (ACTH) stability.


METHODS
We collected blood specimens from 10 donors into K3 EDTA (ethylenediaminetetraacetic acid) and K3 EDTA + aprotinin tubes. Plasma specimens were held at room temperature and at 2 °C to 8[Formula: see text] for 0, 2, 4, 8, 24, and 72 hours. ACTH concentrations in 4 storage conditions were compared with repeated-measures analysis of variance (ANOVA) at each time point.


RESULTS
ACTH concentrations substantially decreased after a 72-hour time period. At the 72nd hour, standard EDTA tubes and EDTA + aprotinin tubes stored at 4[Formula: see text] showed the optimal stability. EDTA + aprotinin tubes stored at room temperature performed more strongly than standard EDTA tubes stored at room temperature.


CONCLUSIONS
Our results show that refrigerated storage is more effective than protease inhibitor addition to maintain ACTH stability. We recommend using aprotinin tubes, especially for specimens standing at room temperature.
Department of Medical Biochemistry, Canakkale Onsekiz Mart University, Faculty of Medicine, Canakkale, Turkey.
Hakan
H
Turkon
Department of Clinical Biochemistry, Silopi State Hospital, Sırnak, Turkey beiot@hotmail.com.
Burak
B
Toprak
Department of Clinical Biochemistry, Tepecik Teaching and Research Hospital, Izmir, Turkey.
Hulya
H
Yalcin
Department of Clinical Biochemistry, Tepecik Teaching and Research Hospital, Izmir, Turkey.
Ayfer
A
Colak
Department of Clinical Chemistry, Ataturk University, Erzurum, Turkey.
Nurinnisa
N
Ozturk
D000293:Adolescent; D000324:Adrenocorticotropic Hormone / Q000097:blood*; D000328:Adult; D007611:Aprotinin / Q000378:metabolism*; D001774:Blood Chemical Analysis / Q000379:methods*; D006801:Humans; D008875:Middle Aged; D015842:Serine Proteinase Inhibitors / Q000378:metabolism*; D013048:Specimen Handling / Q000379:methods*; D013696:Temperature; D055815:Young Adult
D015842:Serine Proteinase Inhibitors; D000324:Adrenocorticotropic Hormone; D007611:Aprotinin
ACTH; aprotinin; preanalytical phase; proteases; stability; temperature