Formulation and evaluation of microemulsion based delivery system for amphotericin B

Area of Science:

• Pharmaceutical Sciences
• Drug Delivery Systems
• Nanotechnology

Background:

• Amphotericin B is a critical antifungal agent but exhibits significant toxicity.
• Conventional formulations like Fungizone are associated with severe side effects.
• There is a need for safer and more effective amphotericin B delivery systems.

Purpose of the Study:

• To develop a lipid-based microemulsion formulation of amphotericin B.
• To characterize the physicochemical properties of the microemulsion.
• To compare the toxicity of the novel formulation with Fungizone.

Main Methods:

• Construction of pseudoternary phase diagrams using Peceol, Mys 40, and Solutol HS 15.
• Co-evaporation of amphotericin B with oil-surfactant mixture.
• Lyophilization of the microemulsion pre-concentrate.
• Characterization of stability, droplet size, and drug aggregation.
• In vitro haemolysis assay and in vivo LD50 determination in mice.

Main Results:

• A stable lyophilized microemulsion formulation of amphotericin B was successfully developed.
• The microemulsion exhibited good stability against freeze-thaw cycles and centrifugation.
• The formulation demonstrated a 92% reduction in human red blood cell haemolysis compared to Fungizone.
• The LD50 in mice was determined to be 3.4 mg/kg.

Conclusions:

• The developed lipid-based microemulsion formulation of amphotericin B is significantly less toxic than Fungizone.
• This novel formulation holds potential as a safer and effective alternative for treating fungal infections.
• Further development could lead to improved patient outcomes in amphotericin B therapy.