用DSC测定小鼠看家基因β-actin的PCR反应体系的比热

Specific Heat Capacity Assay of Mouse β-actingene PCR System Using DSC

本实验用差示扫描量热技术,测量了不同反应循环数的以PCR内参小鼠看家基因β-actin为目的序列的扩增体系在30～94℃温度范围内的比热容。实验发现,在扩增的初期(3～15个循环),反应体系的比热随着循环数的增加,变化不大;在扩增的指数增长期(>20个循环)比热先降低后增加。同一循环,比热随着温度的增加而增加。未经过PCR扩增的反应体系的玻璃化转变温度为-15.29℃。

The specific heat capacity of mouse β-actin gene system in PCR（polymerase chain reaction） was studied in this paper. By the differential scanning calorimeter （DSC）, the specific heat of PCR amplified system with different PCR cycles was assayed. Further, the glass transition temperature of the PCR amplified system was also investigated in the tempera- ture range of -60～50 ℃. Experimental results showed that the more are the PCR cycles, the lower the peak value of the specific heat capacity, but the larger after 26 cycles due to the content of DNA duplexes increasing. The glass transition temperature of PCR system was -15.29 ℃.