Enhanced transdermal controlled delivery of glimepiride from the ethylene-vinyl acetate matrix

Figures & data

Figure 1.  Solubility of glimepiride according to the PEG 400 concentration in solution.

Figure 2.  Relationship between the quinupramine flux and the drug-loading dose in the EVA matrix at 37°C.

Figure 3.  Effects of temperature on the release of quinupramine from the EVA matrix containing various loading doses.

Table 1.  Effects of the citrates on the release of glimepiride from the EVA matrix with 4% loading dose at 37°C.

	flux (μg/cm^2/h^1/2)	Correlation coefficient
Control	49.84 ± 2.36	0.984
ATBC	49.72 ± 3.63	0.999
TBC	63.60 ± 5.45	0.998
TEC	73.44 ± 6.28	0.981
ATEC	77.10 ± 7.35	0.986
DBP	50.51 ± 4.83	0.999
DEP	90.82 ± 6.24	0.990

Table 2.  Enhancement factor according to various enhancers.

Enhancer	Flux (μg/cm^2/h)	EF
control	0.23 ± 0.04	1.00
polyoxyethylene 23-lauryl ether	0.43 ± 0.13	1.87
polyoxyethylene 2-stearyl ether	0.42 ± 0.07	1.83
polyoxyethylene 2-oleyl ether	0.51 ± 0.09	2.22
oleic acid	0.50 ± 0.08	2.17
linoleic acid	0.73 ± 0.15	3.17
caprylic acid	0.42 ± 0.06	1.83
lauric acid	0.62 ± 0.11	2.70
myristic acid	0.66 ± 0.10	2.87
oleoyl macrogol-6 glycerides	0.35 ± 0.06	1.52
caprylocaproyl macrogol-8 glycerides	0.50 ± 0.08	2.17
propylene glycol mono caprylate	0.44 ± 0.09	1.91
propylene glycol laurate	0.41 ± 0.07	1.78
propylene glycol monolaurate	0.46 ± 0.10	2.00
NMP	0.47 ± 0.06	2.04
2-pyrrolidone	0.32 ± 0.11	1.39

Figure 4.  Surface morphology of the matrix before (a, b) or after release (c, d) test by scanning electron microscopy. (a) EVA/Drug; (b) EVA/Drug/DEP; (c) EVA/Drug; (d) EVA/Drug/DEP.