Objective The preparation of lyophilized samples were applied in bacterial count proficiency testing, to assess the homogeneity and stability of samples．Method Bacterial count proficiency testing positive samples and negative samples were made by vacuum freeze drying method in penicillin bottles vacuum packaging and stored at 4 ℃. The uniformity of the proficiency testing samples was evaluated by random sampling, and the stability of proficiency testing samples was kept for 12 weeks. Results Random samples had a preferable accordance ratio, and could keep stable for at least 12 weeks while stored at different temperatures. Suitable bacterial count proficiency testing samples and effective sample preparation and evaluation process were established. Conclusion Effective bacterial count proficiency testing sample preparation method and evaluation process were established
标题：菌落总数能力验证样品均匀性和稳定性的研究
英文标题：Homogeneity and stability of samples used by bacterial count
