Comparison of Pharmaceutical Characterization and Tissue Distribution Between Chuanqi Ophthalmic Microemulsion in situ Gel and Normal in situ Gel / 中国实验方剂学杂志

ABSTRACT

Objective: In this paper,the effect of microemulsion in Chuanqi ophthalmic microemulsion in situ gel was investigated. Method: 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: 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(lgP) was 2.87,which was consistent with the range of lgP of ideal ophthalmic drugs(lgP=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: 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.