Apogee Technology, Inc., 129 Morgan Drive, Norwood, Massachusetts 02062, USA.
Biomacromolecules. 2010 Aug 9;11(8):2033-8. doi: 10.1021/bm100395u.
Degradation of a water-soluble polyphosphazene, poly[di(carboxylatophenoxy)phosphazene], disodium salt (PCPP) has been studied in aqueous solutions at elevated temperature. This synthetic polyelectrolyte is of interest as vaccine adjuvant and its degradability constitutes an important component of its safety and formulation stability profiles. The degradation process is manifested by a gradual reduction in the molecular weight of the polymer and cleavage of side groups, which is consistent with previously reported data on hydrolytical breakdown of water-soluble polyphosphazenes. The kinetics of hydrolytical degradation exhibits distinct pH dependence and the process is faster in solutions with lower pH. Remarkably, a number of hydrogen bond forming additives, such as polyethylene glycol and Tween displayed a dramatic accelerating effect on the degradation of PCPP, whereas inorganic salts, such as sodium chloride and potassium chloride, showed a trend for its retardation. The results can be potentially explained on the basis of acid promoted hydrolysis mechanism and macromolecular interactions in the system.
在高温下的水溶液中研究了水溶性聚膦嗪，聚[二（羧基苯氧基）膦嗪]，二钠盐（PCPP）的降解。这种合成的高分子电解质作为疫苗佐剂很有意义，其可降解性是其安全性和配方稳定性的重要组成部分。降解过程表现为聚合物分子量逐渐降低和侧基裂解，这与以前报道的水溶性聚膦嗪的水解断裂数据一致。水解降解的动力学表现出明显的 pH 依赖性，在 pH 值较低的溶液中，该过程更快。值得注意的是，许多形成氢键的添加剂，如聚乙二醇和吐温，对 PCPP 的降解有显著的加速作用，而无机盐，如氯化钠和氯化钾，则有减缓其降解的趋势。根据酸促进水解的机制和体系中的大分子相互作用，可以对这些结果进行潜在的解释。
