Factor Level used [Coded]
Independent Variables Low [-1] Medium [0] High [+1]
X1= Lipid: drug [w/w] 21.36 26.70 32.40
X2= Lipid: Surfactant [w/w] 4.50 5.00 5.50
X3= Sonication time [min] 10.00 20.00 30.00
Dependent Variables =Y1 [Entrapment Efficiency [%]], Y2 [Particle size [nm]] and Y3 [Transdermal flux [μg/cm2/hr]]
Design Results
Code X1 [w/w] X2 [w/w] X3 [min.] Y1 [%] mean ±  SD, n=3 Y2 [nm] mean ±  SD, n=3 Y3 [ug/cm2/hr] mean ±  SD, n=3
GNTs1 0 0 0 69.10 ± 0.74 145.24 ± 3.48 53.39 ± 4.76
GNTs2 0 0 0 68.80 ± 0.56 142.24 ± 1.89 54.10 ± 3.63
GNTs3 +1 +1 0 59.96 ± 1.21 180.06 ± 5.56 36.65 ± 5.30
GNTs4 -1 0 +1 48.95 ± 1.23 156.15 ± 4.98 40.10 ± 3.81
GNTs5 0 0 0 68.90 ± 1.67 152.76 ± 3.80 53.40 ± 4.76
GNTs6 +1 0 +1 51.18 ± 2.56 166.58 ± 1.24 46.04 ± 2.48
GNTs7 0 +1 -1 86.88 ± 1.33 184.67 ± 3.43 42.78 ± 5.44
GNTs8 -1 0 -1 50.40 ± 0.75 158.32 ± 5.60 47.30 ± 7.20
GNTs9 0 -1 +1 72.68 ± 2.23 151.33 ± 4.69 48.52 ± 5.09
GNTs10 +1 -1 0 42.60 ± 1.32 140.04 ± 2.35 41.57 ± 9.36
GNTs11 0 0 0 69.10 ± 0.98 142.31 ± 1.36 53.39 ± 4.76
GNTs12 0 0 0 68.80 ± 3.34 147.68 ± 3.50 54.10 ± 3.63
GNTs13 +1 0 -1 51.17 ± 2.35 170.24 ± 4.21 36.56 ± 5.49
GNTs14 0 -1 -1 74.61 ± 1.13 175.09 ± 1.25 41.40 ± 3.21
GNTs15 -1 +1 0 54.33 ± 0.87 160.78 ± 2.12 39.94 ± 4.27
GNTs16 0 +1 +1 86.20 ± 4.39 191.23 ± 3.22 38.31 ± 5.04
GNTs17 -1 -1 0 45.59 ± 0.87 154.33 ± 3.89 43.50 ± 4.58
Y1=entrapment efficiency (%); Y2=particle size (nm) and Y3=transdermal flux μg/cm2/hr)
Table 1: Box-Behnken design variables and results.