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Chang-Shun Liu,1– 3 Li Chen,4 Yan-Nan Hu,1– 3 Jin-Lian Dai,4 Biao Ma,4 Qing-Fa Tang,1– 3 Xiao-Mei Tan1– 3 1School of Traditional Chinese Medicine, Southern Medical University, Guangzhou 510515, People’s Republic of China; 2Guangdong Provincial Key Laboratory of Chinese Medicine Pharmaceutics, Southern Medical University, Guangzhou 510515, People’s Republic of China; 3Guangdong Provincial Engineering Laboratory of Chinese Medicine Preparation Technology, Southern Medical University, Guangzhou 510515, People’s Republic of China; 4School of Pharmacy, Zunyi Medical University, Zunyi 563000, People’s Republic of ChinaCorrespondence: Li Chen; Xiao-Mei Tan Email zmu_cl@126.com; tanxm_smu@163.comPurpose: Ferulic acid (FA) is a natural compound which is used to treat insomnia. However, its use is limited because of its poor oral bioavailability caused by extremely rapid elimination. The current study aimed to develop a self-microemulsifying drug delivery system (SMEDDS) to improve the oral delivery of FA and toenhance its hypnotic efficacy.Methods: FA-SMEDDS was prepared, and its morphology and storage stability were characterized. The formulation was also subjected to pharmacokinetic and tissue distribution studies in rats. The hypnotic efficacy of FA-SMEDDS was evaluated in p-chlorophenylalanine-induced insomnia mice.Results: FA-loaded SMEDDS exhibited a small droplet size (15.24 nm) and good stability. Oral administration of FA-SMEDDS yielded relative bioavailability of 185.96%. In the kidney, SMEDDS decreased the distribution percentage of FA from 76.1% to 59.4% and significantly reduced its metabolic conversion, indicating a reduction in renal elimination. Interestingly, FA-SMEDDS showed a higher distribution in the brain and enhanced serotonin levels in the brain, which extended the sleep time by 2-fold in insomnia mice.Conclusion: This is the first study to show that FA-loaded SMEDDS decreased renal elimination, enhanced oral bioavailability, increased brain distribution, and improved hypnotic efficacy. Thus, we have demonstrated that SMEDDS is a promising carrier which can be employed to improve the oral delivery of FA and facilitate product development for the therapy of insomnia.Keywords: insomnia, ferulic acid, oral administration, pharmacokinetics, SMEDDS

The lightweight structure of a mirror in the Fast-steering Mirror(FSM) System was designed.Due to the high specific stiffness and low thermal deformation rate,SiC was used as a raw material to prepare the mirror.The lightweight mirror with a notched structure was supported by three points on the back.Several lightweight structures were analyzed by finite element method.The results show that the rigid of mirror increases with the width of rib.When the rib is wide enough,the rigid of mirror increases slightly.The stress and deformation of mirror caused by gravity increases with mirror thickness.Structure parameters of 4 mm rid and 4 mm mirror thickness are confirmed considering current mechanical manufacture process.The lightweight rate of mirror is 55%.The RMS value of mirror measured by Zygo interferometer is less than λ/30,which is in agreement with that of the analysis.