Figures & data
Figure 1. Pseudo-ternary phase diagram of oil (IPM), water and Smix, presenting microemulsion zones (A) Tween-80:Transcutol-P (1:1), IPM and water (B) Tween-80:Transcutol-P (1:2), IPM and water (C) Tween-80:Transcutol-P (2:1), IPM and water; (D) Tween-80:Transcutol-P (3:1), IPM and water.
Table 1. Few ternary phase compositions and some characterization parameters of o/w microemulsions.
Figure 2. Rheogram (A) and steady-flow viscosity versus shear rate of formulation M/E110 tested a 25 °C (B) (n = 3, ± SD).
Figure 3. TEM microphotograph of microemulsion (M/E110).
Figure 4. Droplet size distributions of the optimized M/E110.
Table 2. Physicochemical characteristics of o/w microemulsion M/E110 of gatifloxacin.
Figure 5. Cumulative drug released versus time (h) curve of formulations M/E101, M/E110, M/E115, M/E210, M/E215, M/E310 and M/E315.
Table 3. Zero-order (K0) and first-order (K1) release rate constants (n = 3, ± SD) with percent coefficient of variation (% CV).
Table 4. Results of stability testing of M/E110 (physicochemical and physical parameters).
Figure 6. Zone of inhibition by the o/w microemulsion (M/E110) and marketed eye drops.
Figure 7. Transcorneal permeation of gatifloxacin from M/E110 and Zigat® eye drops (n = 3, ± SD).
Table 5. Transcorneal permeation parameters of gatifloxacin-containing M/E110 and Zigat® eyedrops (n = 3, ± SD).
Table 6. Ocular irritation studies and summary of paired t-test for mucoidal discharge and eyelid closure.
Figure 8. Precorneal drainage (the percentage of instilled radioactivity remaining in the ocular region as a function of time) of 99mTc-labeled M/E110 and Zigat® eye drops.
Table 7. 99mTc radioactivity remaining in the preocular regions after 10 min (a10) and area under the radioactivity remaining versus time curve (AUC0→10 min) for the two formulation (n = 6, ± SD).
Figure 9. Aqueous humor concentration-time profile of gatifloxacin after topical administration of M/E110 and Zigat® eye drops in rabbit eyes (n = 3, ± SD) up to 6 h.
