当前位置： SCI文献检索 > JOURNAL OF PHARMACEUTICAL SCIENCES期刊下所有文献 > Evaluation of degradation pathways for plasmid DNA in pharmaceutical formulations via accelerated stability studies.

Evaluation of degradation pathways for plasmid DNA in pharmaceutical formulations via accelerated stability studies.

Abstract：

:The stability of highly purified supercoiled plasmid DNA formulated in simple phosphate or Tris-buffered saline solutions has been characterized to establish the overall degradation processes that occur during storage in aqueous solution. Plasmid DNA stability was monitored during accelerated stability studies (at 50 degrees C) by measurements of supercoiled, open-circle, and linear DNA content, as well as the accumulation of apurinic sites and 8-hydroxydeoxyguanosine residues over time. The effects of formulation pH, demetalation, metal ion chelators, and ethanol (hydroxyl radical scavenger) on the supercoiled content of plasmid DNA during storage at 50 degrees C were also determined. The results indicate that free radical oxidation may be a major degradative process for plasmid DNA in pharmaceutical formulations unless specific measures are taken to control it by the addition of free radical scavengers, specific metal ion chelators, or both. The generation of hydroxyl radicals in phosphate-buffered saline was confirmed by examining the hydroxylation of phenylalanine over time by reverse phase high-performance liquid chromatography. Ethanol was found to enhance plasmid DNA stability and to inhibit the hydroxylation of phenylalanine; both observations are consistent with the known ability of ethanol to serve as a hydroxyl radical scavenger. Moreover, the combination of ethylenediamine tetraacetic acid (EDTA) and ethanol had a synergistic enhancing effect on DNA stability. However, the metal ion chelator diethylenetriaminepentaacetic acid (DTPA) was as potent as the combination of EDTA and ethanol for enhancing the stability of plasmid DNA. By controlling free radical oxidation with EDTA and ethanol, the rate constants of plasmid DNA degradation by means of depurination and beta-elimination were then determined, allowing accurate predictions of DNA storage stability as a function of formulation pH and temperature. The ability to predict plasmid DNA storage stability in the absence of free radical oxidation should prove to be a valuable tool for the design of stable pharmaceutical formulations of plasmid DNA.

journal_name

J Pharm Sci

journal_title

Journal of pharmaceutical sciences

authors

Evans RK,Xu Z,Bohannon KE,Wang B,Bruner MW,Volkin DB

doi

10.1002/(SICI)1520-6017(200001)89:1<76::AID-JPS8>3

subject

Has Abstract

pub_date

2000-01-01 00:00:00

pages

76-87

issue

eissn

0022-3549

issn

1520-6017

pii

S0022-3549(16)30539-1

journal_volume

pub_type

杂志文章

在线工具

Evaluation of degradation pathways for plasmid DNA in pharmaceutical formulations via accelerated stability studies.