The Effect of Dilution with 10% Dextrose Solution on the Potency of Botulinum Toxin A

Purpose: The aim of this study was to compare the potency-stabilizing effects of two different diluents of botulinum toxin A (10% dextrose solution and 0.9% saline). Methods: A mouse lethality bioassay was undertaken. Ninety mice were divided into experimental and control groups which received varying dosages in subgroups of 10. The experimental group was injected with botulinum toxin A diluted with 10% dextrose solution and the control group was injected with botulinum toxin A diluted with 0.9% saline. A 72 hours after intraperitoneal injection, the number of dead mice was counted to confirm median lethal dose ($LD_{50}$) of each group. Results: The value of $LD_{50}$ in the experimental group was approximately 0.131 mL (1.31 U) and the value of $LD_{50}$ in the control group was approximately 0.107 mL (1.07 U). The potency preservation rate of the experimental group was estimated to be 93.5% and that of the control group was estimated to be 76.3%. Conclusions: Dilution with 10% dextrose solution displayed less potency loss than 0.9% saline.