Identification of a spurious band on serum protein electrophoresis induced by ethanol treatment.
BACKGROUND
Treatment of serum with ethanol at 100 ml/l eliminating fibrinogen from electrophoretic pattern produces an additional band at alpha2/beta junction. This study is to determine the source and the nature of this artifact.


METHODS
The supernatant after ethanol precipitation was used for electrophoresis. Protein concentrations of each fraction in ethanol- and saline-treated samples were compared, and immunofixation electrophoresis (IFE) to identify transferrin, C3, and LDL was performed. C3 IFE was also conducted for fresh sera and sera stored for 2 weeks.


RESULTS
The artificial band at alpha2/beta junction was identified in ethanol-treated sera but not in saline-treated sera. Protein concentration in the beta fraction was reduced after ethanol treatment as compared to saline-treated samples (n=10, p<0.01). The spurious band at alpha2/beta junction was recognized in C3 IFE. C3 IFE also showed a band at alpha2/beta junction in samples stored for 2 weeks.


CONCLUSIONS
Ethanol treatment of serum creates an artificial band with C3 immunoreactivity at alpha2/beta junction. This could be due to the accelerated hydrolysis of C3 by ethanol treatment. Laboratories using ethanol to evaluate a possible fibrinogen band should be aware of this phenomenon, and the serum protein electrophoretic pattern after ethanol treatment should only be used to rule out fibrinogen.
Zhu
Yusheng
Y
Department of Pathology and Laboratory Medicine, University of Louisville School of Medicine, Louisville, KY 40292, USA.
Elin
Ronald J
RJ
D016477:Artifacts; D001797:Blood Protein Electrophoresis / Q000379:methods; D001798:Blood Proteins / Q000032:analysis* / Q000187:drug effects; D000431:Ethanol / Q000494:pharmacology*; D015203:Reproducibility of Results
D001798:Blood Proteins; D000431:Ethanol