AAPS PharmSciTech

, 20:32 | Cite as

A Novel Phytantriol-Based Lyotropic Liquid Crystalline Gel for Efficient Ophthalmic Delivery of Pilocarpine Nitrate

  • Xingqi Wang
  • Yong Zhang
  • Jie Huang
  • Chunling Tian
  • Mengqiu Xia
  • Liu Liu
  • Zhengguang Li
  • Jiaojiao Cao
  • Shuangying Gui
  • Xiaoqin ChuEmail author
Research Article


The purpose of this paper was to investigate the potential of liquid crystalline (LC) gels for ophthalmic delivery, so as to enhance the bioavailability of pilocarpine nitrate (PN). The gels were prepared by a vortex method using phytantriol and water (in the ratio of 73:27 w/w). Their inner structures were confirmed by crossed polarized light microscopy, small-angle X-ray scattering, attenuated total reflectance-Fourier transform infrared spectrum, and rheology. The in vitro release studies revealed that PN could keep sustained release from the gels over a period of 12 h. The ex vivo apparent permeability coefficient of the gels demonstrated a 3.83-folds (P < 0.05) increase compared with that of eye drops. The corneal hydration levels of the gel maintained in the normal range of 79.46 ± 2.82%, hinting that the gel could be considered non-damaging and safe to the eyes. Furthermore, in vivo residence time evaluation suggested that a better retention performance of LC gel was observed in rabbit’s eyes compared to eye drops. In vivo ocular irritation study indicated that LC gel was nonirritant and might be suitable for various eye applications. In conclusion, LC gels might represent a potential ophthalmic delivery strategy to overcome the limitations of eye drops.


phytantriol liquid crystalline gel cubic phase ophthalmic delivery pilocarpine nitrate 



The authors gratefully acknowledge support from the National Natural Science Foundation of China (No. 81803831, 81873019, 81573615), Key University natural science research project of Anhui province (KJ2018A0301), Anhui Provincial Talents Project for youth in Universities (No. gxyq2018025), Exploratory Research Projects of Anhui University of Chinese Medicine (RD18200130), and Anhui Provincial Natural Science Foundation (No. 1408085QH183). The authors express special thanks to Dr. Xiaoqin Chu for useful communication.

Compliance with Ethical Standards

All animal studies were carried out in accordance with the guidelines for assessment and approval by the ethics committee of Anhui University of Chinese medicine (Hefei, China).

Conflict of Interest

The authors declare that they have no conflict of interest.


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Copyright information

© American Association of Pharmaceutical Scientists 2019

Authors and Affiliations

  • Xingqi Wang
    • 1
  • Yong Zhang
    • 1
  • Jie Huang
    • 1
  • Chunling Tian
    • 1
  • Mengqiu Xia
    • 1
  • Liu Liu
    • 1
  • Zhengguang Li
    • 1
  • Jiaojiao Cao
    • 1
  • Shuangying Gui
    • 1
    • 2
  • Xiaoqin Chu
    • 1
    • 2
    • 3
    Email author
  1. 1.Department of Pharmaceutics, College of PharmacyAnhui University of Chinese MedicineHefeiChina
  2. 2.Institute of PharmaceuticsAnhui Academy of Chinese MedicineHefeiChina
  3. 3.Department of PharmacyAnhui University of Chinese MedicineHefeiChina

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