Formulation and Optimization of Polymeric Nanoparticles for Intranasal Delivery of Lorazepam Using Box-Behnken Design: In Vitro and In Vivo Evaluation

Table 1

Independent and dependent variables levels in Box-Behnken design.

	Levels
	−1	0	1
Independent variables
𝑋1 = polymer concentration (w/v)	10	35	60
𝑋2 = surfactant concentration (w/v)	2	8.50	15
𝑋3 = aqueous/organic phase ratio (v/v)	2	6	10
𝑋4 = drug concentration (w/v)	1	3	5
Dependent Variables:	Constraints
𝑌1 = 𝑧-average (d·nm)	Minimize
𝑌2 = % drug entrapment	Maximize