Table 1. Coded levels and “Real” values for each factor under study.

Variables	Levels
	-1.732	-1	0	+1	+1.732
Independent	Real values
Drug: Phospholipid ratio (X1, mol: mol)	0.5	1.11	2	2.89	3.5
Reaction temperature (X2, °C)	40	44	50	56	60
Reaction time (X3, mins)	60	84	120	156	180
Dependent
Entrapment efficiency (Y, % w/w)