Objective:

2

In this paper

the effect of microemulsion in Chuanqi ophthalmic microemulsion

in situ

gel was investigated.

Method:

2

The effect of microemulsion was confirmed by the parallel comparison between the Chuanqi microemulsion

in situ

gel and normal

in situ

gel

including study of pharmaceutical characterization and tissue distribution.

Result:

2

The average particle sizes of Chuanqi microemulsion

in situ

gel and normal

in situ

gel were (38.20±0.13) nm and (985±37) nm

respectively.Microemulsion could maintain the properties of nanocarrier in a microemulsion

in situ

gel composite system.The result of tissue distribution study showed that only ligustilide could be detected.This was related to the nature of these three indicator components(ligustrazine

ligustilide and astragaloside A). The common logarithm of oil and water partition coefficient of ligustilide(lg

P

) was 2.87

which was consistent with the range of lg

P

of ideal ophthalmic drugs(lg

P

=2.0-3.0). The ligustilide from Chuanqi microemulsion

in situ

gel could be detected in the cornea

vitreous body and retina

and this compound from normal

in situ

gel could only be detected in the cornea with low content.At the same time

microemulsion could increase the content of ligustilide in corneal tissues.

Conclusion:

2

The characteristics of microemulsion nanocarriers can increase the solubility of ligustilide

compared with normal

in situ

gel

it can be better distributed in the tears outside the corneal

it reaches the cornea with a higher concentration

and forms a corneal concentration gradient

and ligustilide is transported from the anterior ocular region to the posterior ocular region through the transocular barrier.