Abstract: Objective To analyze the stability of hepatitis C virus（HCV）in serum and its purified nucleic acid at different temperatures. Methods Anti-HCV-negative plasma obtained from the Blood Center was used as the diluent. The 10⁷ IU/mL HCV serum was diluted to 10⁵ IU/mL and 10³ IU/mL. Total RNA was extracted and purified. Fluorescence quantitative polymerase chain reaction（FQ-PCR）was used to determine three serum concentrations. The remaining serum and its nucleic acid were packed into 45 aliquots and stored at 25 ℃, 4℃and -20 ℃ respectively. The serum and nucleic acid were taken out to detect viral load changes after storage at 1 day, 3 days, 6 days, 9 days, 12 days, 15 days, 18 days, 21 days, 28 days, 35 days, 42 days, 49 days, 56 days, 63 days and 70 days. The experiments were repeated three times, and the mean and standard deviation were calculated. Results HCV viral load showed a downward trend over extended storage time（P<0.05）; the viral loads were correlated to time, storage temperature and initial concentration（P<0.05）; there were significant differences between10⁷ IU/mL、10⁵ IU/mL and 10³ IU/mL storage for the same time and at different temperatures（P<0.05）. There was no significant difference in HCV viral load between at 4 ℃and -20 ℃（P>0.05）, but there was significant difference between at them and 25 ℃（P<0.05）. HCV purified nucleic acid concentration levels of 10³ IU/mL, 10⁵ IU/mL and 10⁷ IU/mL were stored at 25 ℃, 4℃ and -20 ℃ for 70 days, and the concentration change was negatively correlated with the initial concentration（P<0.05）. Conclusion HCV serum stored at 4 ℃or -20 ℃ can maintain the stability. The higher the viral load, the better the stability. HCV purified nucleic acid was stored at 25℃, 4 ℃and -20 ℃ for 70 days, and its concentration change was negatively correlated to the initial concentration.

Key words: Hepatitis C virus, Serum, Purified nucleic acid, Stability, Storage