Formulation and evaluation of Cyclosporin A emulgel for ocular delivery

Figures & data

Figure 1. Viscosity-shear rate profiles of CsA emulgel.

Table 1. The stability of CsA emulgel.

Month	0	1	3
Content	99.85%	99.57%	99.63%
Viscosity (cP)	1888	1917	1924
pH	6.66	6.67	6.66
Osmotic pressure (mOsmol/kg)	301	308	303
Appearance	Milk white, not layed	Milk white, not layed	Milk white, not layed

Figure 2. The effects of concentration and viscosity of gel on the release behavior of CsA emulgel.

Figure 3. Concentration–time profiles of CsA in tear fluid after instillation in conscious rabbits (n = 5).

Table 2. Parameters based on statistical moment theory for CsA in tear fluid after topical administration in conscious rabbits (n = 6).

Pharmacokinetics parameters	CsA emulgel group	CsA castor oil group
AUC (μg*h/mL)	18.21**	8.31
AUMC (μg*h^2/mL)	155.13**	55.89
MRT (h)	8.52*	6.72

AUC, area under the curve; MRT, mean retention time; AUMC, area under the moment curve. **p < 0.01, *p < 0.05.

Table 3. Mean tear concentration of CsA after instillation of E-gel preparation and castor oil preparation in rabbit(mg/ml, $\overline{X}\pm SD$, n = 6).

Time (h)	CsA E-gel group (μg/g)	CsA castor oil group (μg/g)
0.08	3.97 ± 0.74	3.05 ± 0.92
0.50	3.07 ± 0.64	1.78 ± 0.25
1.00	2.54 ± 0.16	2.86 ± 0.96
2.00	1.89 ± 0.50	2.03 ± 0.52
3.50	1.29 ± 0.24	1.40 ± 0.49
7.00	0.69 ± 0.06	0.90 ± 0.30
14.00	0.29 ± 0.05	0.52 ± 0.07
24.00	0.18 ± 0.02	0.47 ± 0.43

Figure 4. Light microscopy of rabbit’s iris (A, B), rabbit’s conjunctiva (C, D), and rabbit’s corneal tissue sections (E, F), from CsA emulgel-treated (OD) and control (OS) rabbit eyes. Samples and tissue sections from treated eyes showed no alterations in morphological details compared to control eyes. Eye tissues from CsA emulgel-treated animals gave similar results. Staining: (A–F) hematoxylin-eosin. Scale bar = 100 μm.