Preformulation Study of Prokidin : Chemical Stability

  • Lee, Yun-Jin (College of Pharmacy, Dongduk Women's University) ;
  • Chun, In-Koo (College of Pharmacy, Dongduk Women's University)
  • Published : 2001.11.01

Abstract

The effects of pH and temperature on the degradation of prokidn in various buffered aqueous solutions(pH 1.32~9.66) and temperatures (35, 45 and 6$0^{\circ}C$ were investigated. The effect of ionic strength on the degradation of prokidin was also measured by varying ionic strength (0.0466~1.5) at pH 1.35 and 45$^{\circ}C$ The effect of metal ions on the degradation of prokidin at pH 7.35 and 3.98 was observed. The degradation of prokidin followed the pseudo- first- order kinetics. The degradation rate of prokidin showed pH-dependent and temperature-dependent patterns. Prokidin was very stable at the pH below 3.95, where half-lives at 35, 45 and 6$0^{\circ}C$were 294, 206 and 107 day, respectively. However, it degraded very rapidly at pH above 6.49; the half-lives at 35, 45 and 6$0^{\circ}C$were 60, 25 and 13 day, respectively. As ionic strength increased, the degradation rate of prokidin increased. Some metal ions increased the degradation rate in the rank order of Mn > Fe > Cu >Fe On the other hand. other metal ions such as Bi, Ba. Zn, Ni, Co did not show unfavorable effect.

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