Temperature-dependent effect of edetate disodium on neomycin stability

Area of Science:

• Pharmaceutical Science
• Drug Stability
• Ophthalmic Formulations

Background:

• Neomycin is a widely used antibiotic in ophthalmic preparations.
• Understanding factors affecting neomycin stability is critical for ensuring therapeutic efficacy.
• Edetate disodium is a common chelating agent used in pharmaceutical formulations.

Purpose of the Study:

• To investigate the effect of edetate disodium on the stability of neomycin in aqueous ophthalmic formulations.
• To determine the influence of temperature on the interaction between edetate disodium and neomycin.

Main Methods:

• Aqueous solutions of neomycin with 0.01% edetate disodium were prepared.
• Formulations were subjected to varying temperatures (above 100 degrees and at 30 degrees).
• Neomycin stability was assessed under different thermal conditions.

Main Results:

• Edetate disodium significantly improved neomycin stability at temperatures exceeding 100 degrees Celsius.
• At a lower storage temperature of 30 degrees Celsius, edetate disodium addition was found to be detrimental to neomycin stability.
• The stabilizing effect of edetate disodium was temperature-dependent, with a reversal of effect at lower temperatures.

Conclusions:

• The impact of edetate disodium on neomycin stability in ophthalmic solutions is critically dependent on temperature.
• Careful consideration of storage temperature is necessary when formulating neomycin with edetate disodium.
• Optimizing ophthalmic formulation stability requires understanding excipient-drug-temperature interactions.