The effect of protective agents on the stability of plasmid DNA by the process of spray-drying.
The effect of several protective agents was assessed on the stability of spray-dried plasmid DNA. The spray-drying process had adverse effects on the tertiary structure of plasmid DNA with the protective agents of sucrose, glycine and agarose. With the protection of these noncondensing agents, a band corresponding to the linear form of plasmid DNA was observed in the gel electrophoresis between the supercoiled circular (SC) form and the open circular (OC) form. On the contrary, spray-dried plasmid DNA maintained some degree of structural integrity under the protection of condensing agents. For the protection by neutral condensing polymers, such as polyethylene glycol 1000 and 4000, no linear form between the SC form and the OC form of plasmid DNA was revealed in the gel electrophoresis. Also, excess cationic condensing polymer, polyethyleneimine, had the ability to provide the plasmid DNA with protection from degradation as indicated by the preservation in SC and OC forms of plasmid DNA on the agarose gel electrophoresis. Moreover, DNA topology was unchanged after six-month storage at 4 degrees C by the protection of these neutral and cationic condensing agents. Accordingly, DNA condensation induced by condensing agents may provide a way to minimize damage to plasmid DNA by the process of spray drying.
Kuo
Jung-hua Steven
JH
Department of Pharmacy, Chia Nan University of Pharmacy and Science, 60 Erh-Jen Rd., Sec. 1, Jen-Te, Tainan 717, Taiwan, ROC. ph0510@yahoo.com
D004247:DNA / Q000737:chemistry*; D003890:Desiccation; D004587:Electrophoresis, Agar Gel; D004926:Escherichia coli / Q000235:genetics; D005998:Glycine / Q000737:chemistry; D010957:Plasmids / Q000737:chemistry* / Q000235:genetics; D011092:Polyethylene Glycols; D011094:Polyethyleneimine; D012685:Sepharose / Q000737:chemistry; D013314:Stress, Mechanical; D013395:Sucrose / Q000737:chemistry; D013501:Surface-Active Agents; D013696:Temperature
D013501:Surface-Active Agents; D011092:Polyethylene Glycols; D013395:Sucrose; D011094:Polyethyleneimine; D004247:DNA; D012685:Sepharose; D005998:Glycine