Stability of an anti-stroke peptide: driving forces and kinetics in chemical degradation.

Abstract

NR2B9c (Lys-Leu-Ser-Ser-Ile-Glu-Ser-Asp-Val) is a 9-amino acid peptide that has been illustrated to be a potential anti-stroke drug. For more effective treatment, suitable drug delivery systems should be developed. However, little is known about the stability of NR2B9c which is essential to its formulation. In this study, a reversed-phase high-performance liquid chromatography (HPLC) was applied to study the forced degradation behavior and stability of NR2B9c. HPLC studies were performed with an C8 column using a mobile phase consisting of acetonitrile (14.5:85.5, v/v) and aqueous solution (0.1% trifluoroacetic acid (TFA) and 0.05 M KH2PO4). The flow rate and the wavelength set during HPLC detection were 1.0 mL/min and 205 nm, respectively. The degradation pattern of NR2B9c aqueous solution followed pseudo first-order kinetics. The degradation rate at pH 7.5 was the slowest according to the plotting V-shaped pH-rate profile. The influence of temperature on the rate of reactions was interpreted in terms of Arrhenius equation (r(2)>0.98). Thermodynamic parameters were calculated based on Eyring equation (r(2)>0.98). The concentrations of drug, buffer species, buffer concentrations, oxidation and organic solvents have noticeable effects on the degradation of NR2B9c while ultrasound shows little impact under the experimental conditions. In a word, this study may give a detailed description of stability of NR2B9c.

• Authors: Rui Li, Fengzhen Wang, Li Chen, Shuning Zhu, Lin Wu, Sunmin Jiang, Qunwei Xu, Dongya Zhu
• Journal: International journal of pharmaceutics (Int J Pharm) Vol. 472 Issue 1-2 Pg. 148-55 (Sep 10 2014) ISSN: 1873-3476 [Electronic] Netherlands
• PMID: 24929015 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)
• Copyright: Copyright © 2014. Published by Elsevier B.V.

Chemical References

• Neuroprotective Agents
• Oligopeptides
• Oxidants
• Hydrogen Peroxide

Topics

• Chromatography, High Pressure Liquid
• Drug Stability
• Hydrogen Peroxide (chemistry)
• Hydrogen-Ion Concentration
• Kinetics
• Light
• Neuroprotective Agents (chemistry, radiation effects)
• Oligopeptides (chemistry, radiation effects)
• Osmolar Concentration
• Oxidants (chemistry)
• Oxidation-Reduction
• Sonication
• Stroke (drug therapy)
• Temperature