Objective To discuss the factors that affect the synthesis of ¹¹C-acetate via a domestic automated solid-phase extraction method.

Methods The synthesis efficiency of ¹¹C-acetate was influenced by the release rate of ¹¹CO₂ from the cyclotron target, the release time of ¹¹CO₂ by the capture ring, the concentration and volume of tetrahydrofuran(THF) with CH₃MgBr, nitrogen current rate and pressure, water in the synthesis system. Thus, these parameters were optimized.

Results After performing 18 runs of the conditional parallel experiment, the synthesis efficiency of ¹¹C-acetate was increased to(53.7±3.6)%, and the radiochemical purity was more than 99%.

Conclusion The main factors that affect the efficiency of ¹¹C-acetate synthesis were the concentration and volume of CH₃MgBr/THF, the current rate of nitrogen, and the pressure of nitrogen.