目的:考察利用微量热法研究磁性生物材料与大肠杆菌相互作用的优势。方法:将大肠杆菌与磁性生物材料共同培养,利用微量热仪记录大肠杆菌的生长放热曲线,分析拟合获得大肠杆菌生长过程的热动力学参数。然后观察大肠杆菌的显微形态,并分析其形态变化。同时利用光电比浊法测定大肠杆菌的密度。结果:磁性生物材料导致大肠杆菌的生长速率常数降低,菌液最大放热功率下降,生长代谢受到抑制。而电镜观察发现,与磁性生物材料共同培养的大肠杆菌菌体萎缩变形,细胞壁出现褶皱和破损。与光电比浊法的研究结果相比,微量热法的研究结果能更符合电镜观察结果。结论:磁性生物材料破坏了大肠杆菌的细胞壁,导致大肠杆菌生长代谢受到抑制。此外,微量热法有助于研究磁性生物材料与细菌的相互作用。
Objective:To investigate the interaction of magnetic biomaterial and Escherichia coli(E.coli),and evaluate the advantages of microcalorimetry in this object.Methods:E.coli was seeded on magnetic biomaterial and a microcalorimeter was used to record the metabolic thermogenic curves.The thermokinetic parameters of E.coli growth were calculated and analyzed.The changes in the morphology of E.coli were investigated.The density of E.coli was also tested by phototurbidometry.Results:The growth rate constant and maximum heat output power of E.coli seeded on magnetic biomaterial decreased compared to E.coli cultured in other groups,indicating that the metabolism of E.coli was inhibited.Further investigation by scanning electron microscopy revealed that the morphology of E.coli seeded on magnetic biomaterial was shriveled and distorted,and the cell wall was damaged.Compared with the phototurbidometry,the results of microcalorimetry are more correlative to the results of SEM.Conclusions:Magnetic biomaterial can damage the cell wall of E.coli,which will result in inhibition of the metabolism of E.coli.And this interaction between them can be well investigated by microcalorimetry.