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

Topical lidocaine microemulsion preparations with low toxicity, low irritation, strong transdermal capability and convenient administration are urgently needed. Box-Behnken design was performed for three preparation conditions of 5% lidocaine microemulsions: mass ratio of the mass ratio of surfactant/(oil phase + surfactant) (X), the mass ratio of olive oil/(α-linolenic acid + linoleic acid) (X) and the water content W% (X). Then, five multi-objective genetic algorithms were used to optimize the three evaluation indices to optimize the effects of lidocaine microemulsion preparations. Finally, the ideal optimization scheme was experimentally verified. Non-dominated Sorting Genetic Algorithm-II was used for 30 random searches. Among these, Scheme 2: X = 0.75, X = 0.35, X = 75%, which resulted in Y = 0.17 μg/(cm·s) and Y = 0.74 mg/cm; and the Scheme 19: X = 0.68, X = 1.42, X = 75% which resulted in Y = 0.14 μg/(cm·s) and Y = 0.80 mg/cm, provided the best matches for the objective function requirements. The maximum and average fitness of the method have reached stability after 3 generations of evolution. Experimental verification of the above two schemes showed that there were no statistically significant differences between the measured values of Y and Y and the predicted values obtained by optimization ( > 0.05) and are close to the target value. Two lidocaine microemulsion preparation protocols were proposed in this study. These preparations resulted in good transdermal performance or long anesthesia duration, respectively.