A study on the preparation conditions of lidocaine microemulsion based on multi-objective genetic algorithm

Area of Science:

• Pharmaceutical Sciences
• Drug Delivery Systems
• Formulation Development

Background:

• Urgent need for topical lidocaine microemulsions with low toxicity and irritation.
• Requirement for formulations with strong transdermal capability and convenient administration.
• Existing topical anesthetics may lack optimal characteristics for widespread use.

Purpose of the Study:

• To develop and optimize 5% lidocaine microemulsion formulations.
• To enhance transdermal capability and anesthetic duration of topical lidocaine.
• To identify optimal preparation conditions using a systematic approach.

Main Methods:

• Box-Behnken design employed to study three preparation variables: surfactant ratio (X1), oil ratio (X2), and water content (X3).
• Five multi-objective genetic algorithms, including Non-dominated Sorting Genetic Algorithm-II, used for optimization.
• Experimental verification of optimized formulations to validate predicted performance.

Main Results:

• Two optimal schemes identified: Scheme 2 (X1=0.75, X2=0.35, X3=75%) and Scheme 19 (X1=0.68, X2=1.42, X3=75%).
• Scheme 2 yielded high transdermal flux (Y1=0.17 μg/cm²/s), while Scheme 19 showed a higher drug retention (Y2=0.80 mg/cm²).
• Experimental results closely matched predicted values (p > 0.05), confirming the optimization models.

Conclusions:

• Two distinct lidocaine microemulsion preparation protocols were successfully developed.
• These protocols offer tailored benefits: one for superior transdermal performance, the other for extended anesthesia duration.
• The optimized formulations represent significant advancements in topical anesthetic delivery.