I-Optimal Quadratic Response Surface Experimental Design

After preparing MX-loaded SNEDDS using PO (MX-PO-SNEDDS), as the oil component, it was important to study the effects of various formulation components for optimization. The I-optimal quadratic response surface experimental design was employed to optimize the MX-PO-SNEDDS formulation, the details of which are provided in Table 1. Three independent factors were selected, including the PO:MCT ratio, HLB for surfactant mixture, and MX:oil mix ratio. The measured responses were particle size of emulsion droplets, stability index, ex vivo steady-state flux across the membrane (Jss), and the ulcer index. In total, 18 randomly ordered runs with 7.5 mg MX in each formulation were performed. About 1 g of each suggested formulation was prepared. The total of three components (oil mixture, surfactant, and co-surfactant) in the mixture was maintained equal to 100%.

The independent factors and responses for the design of experiments.

PO = peppermint oil, MCT = Medium chain triglyceride; HLB = Hydrophilic lipophilic balance; MX = Meloxicam.