OBJECTIVE: To probe into the effect of different preservation conditions on monitoring the blood concentration of cyclosporine in whole blood sample. METHODS: A total of 80 discarded samples for routine monitoring of blood concentration were collected from this hospital

each sample was mixed and evenly divided into 3 parts

which were preserved at room temperature（20-25 ℃）

refrigerated（2-8 ℃） and frozen（-35--30 ℃） away from light for 7 days. Chemiluminescence microparticle immunoassay was adopted to detect the blood concentration of cyclosporine under different preservation conditions. RESULTS: The concentrations of cyclosporine were（213.0±128.3） ng/mL at room temperature and（207.4±121.7） ng/mL at frozen condition for 7 days

which had no statistically significant differences compared with the blood concentrations of（212.0±123.5） ng/mL measured on the sampled day（P=0.792

P=0.188）; while the concentration of cyclosporine at refrigerated condition for 7 days was（198.4±113.8） ng/mL

which was 6.6% lower than that measured on the sampled day

with statistically significant difference（P=0.002）. CONCLUSIONS: The blood concentration of cyclosporine is generally decreased after 7 days of refrigeration

while 7 days of preservation at room temperature or frozen have no effect on the blood concentration of cyclosporine. If the cyclosporine sample cannot be detected in time on the day of sampling

it can be preserved at room temperature or frozen away from light

and the determination should be completed within 7 days.