摘要目的:探讨可能影响mRNA疫苗粒径和粒径分布的因素。方法:在不同离子强度缓冲液、pH值、稀释剂类型、稀释度和检测仪器条件下，采用动态光散射法对3批mRNA疫苗的粒径和粒径分布进行检测。结果:稀释剂的离子强度增大时，疫苗的粒径随之增大，粒径分布不发生改变；稀释剂的pH值增加时，疫苗的粒径随之增大，当pH值达到弱碱性时，粒径分布出现明显变化；选择不同溶液作为稀释剂时，mRNA疫苗的粒径均不同，粒径分布无明显变化；疫苗稀释度≤100时，粒径和粒径分布均无明显改变；不同仪器参数下疫苗的粒径和粒径分布差异无统计学意义，但粒径分布略有不同。结论:粒径和粒径分布受稀释剂、稀释度和检测仪器等因素影响，在生产与质控中应予以关注。

abstractsObjective:To investigate the factors that could influence the particle size and size distribution of mRNA vaccines.Methods:The influences of several factors including the ionic strength and pH values of buffers, solutions, dilution folds and testing equipments on the particle size and size distribution of three batches of mRNA vaccines were analyzed by dynamic light scattering.Results:The particle size increased with increasing ionic strength, but no significant change in size distribution was observed. The particle size also increased with increasing pH values and the size distribution showed significant change when the buffer solution was weakly alkaline. Solution types could affect the particle size, but had no influence on size distribution. There was no significant change in the particle size or size distribution when the dilution was limited to 100 folds. Moreover, the particle size and size distribution detected by different equipments showed no significance difference.Conclusions:The particle size and size distribution of mRNA vaccines could be affected by solution, dilution fold and testing equipment, which should be concerned during the vaccine production and quality control.