[Preparation and in vitro anti-hepatic fibrosis evaluation of herpetone nanosuspensions]

Herpetone( HPT) is a bioactive lignan extracted from Herpetospermum pedunculosum,which can protect liver,lower aminotransferase and inhibit hepatitis B virus. However,HPT has a poor oral bioavailability due to its poor water solubility. And there is no report about whether HPT has an anti-hepatic fibrosis activity. To improve the dissolution of HPT and study its anti-hepatic fibrosis activity and mechanism,the study group prepared herpetone nanosuspensions( HPT-NS) by the miniaturized media milling method. The formulation and process of HPT-NS were optimized by the single factor experiment. Scanning electron microscopy was used to observe morphology of HPT-NS. Dialysis method was used to study dissolution of HPT-NS in vitro. CCK8 method was used to assess the effect of HPT-NS on proliferation of the rat hepatic stellate cells( HSC-T6). Flow cytometry was used to assess the effect of HPT-NS on apoptosis and cell cycle of HSC-T6. The mean particle size of optimized HPT-NS was( 196±7) nm with a polydispersity index of 0.279±0.009.SEM showed that HPT-NS was in a regular rod shape. The cumulative dissolution rate of HPT-NS reached 93% in 18 h,and was higher than that of herpetone coarse suspensions( HPT-CS,28%). CCK8 experiment showed that the inhibition rate of HPT-NS on HSC-T6 was higher than that of HPT-CS. Flow cytometry showed that HPT-NS could block HSC-T6 cells in G2/M phase and induce apoptosis of HSC-T6 cells,with a significantly stronger effect than HPT-CS. The results revealed that HPT-NS significantly increased the in vitro dissolution of HPT,and enhanced the inhibitive effect on HSC-T6 cell proliferation by blocking cells in the G2/M phase and inducing late apoptosis.

[Preparation of astilbin amorphous nanosuspension and its in vitro evaluation]

Astilbil nanosuspension (AT-NS) was prepared by an antisolvent precipitation method. The formula and process of AT-NS were optimized by the single factor experiment. AT-NS was prepared under the optimal conditions, and its morphology and crystallinity were characterized. In vitro release of AT-NS was also determined. The particle size of AT-NS stabilized by PVP K30 was (149±3) nm, and the polydispersity index (PDI) and stability index (SI) were 0.137±0.014 and 0.940±0.012, respectively. The results of SEM showed that AT-NS was spherical. Both XRD and DSC showed that AT was amorphous in nanosuspension. In the in vitro release test, AT-NS showed a significantly increased dissolution. This simple low-cost approach could prepare AT-NS successfully. AT-NS could significantly improve the dissolution of AT and provide the reference to break the limitation on the clinical application of AT.

[Study on preparation of volatile oil from Acorus tatarinowii self-nanoemulsion dropping pills and its protective effect on acute myocardial ischemia injury]

In this study, solid dispersion technology was used to develop volatile oil from Acorus tatarinowii self-nanoemulsion dropping pills(VOA-SNEDDS-DP) and its protective effect on acute myocardial ischemia injury was evaluated. Taking exterior quality, weight variation and the resolving time as comprehendsive evaluation indexes, the preparation process and formulation of the dropping pills were optimized by orthogonal design, and the dissolution rate in vitro of the optimized VOA-SNEDDS-DP was investigated. The rat model of acute myocardial ischemia was induced by intraperitoneal injection of isoproterenol hydrochloride and the serum levels of superoxide dismutase(SOD), malondialdehyde(MDA), creatine kinase(CK) and pathological changes of myocardial tissue were determined to evaluate therapeutic effect of the dropping pills on acute myocardial ischemia. The results showed that the optimal formulation and preparation process of VOA-SNEDDS-DP were as follows: PEG6000-PEG8000 was 1∶1, proportion of VOA-SNEDDS and matrix was l∶2.5, the temperature of drug fluids was 75 ℃, drop rate was 35 drops/min, drop distance was 5 cm, the condensing agent temperature was 2-10 ℃. The content of β-asarone in the dropping pills was 42.46 mg·g~(-1). The accumulated dissolution rate of the dropping pills reached 93.85% in 10 min. The results of pharmacodynamic experiments showed that VOA-SNEDDS-DP could significantly increase the SOD content(P<0.05), reduce the levels of MDA and CK(P<0.05) in serum, and effectively improve the pathological morphology of myocardial tissue. These results revealed that the preparation of VOA-SNEDDS-DP by solid dispersion technology was stable and feasible, and VOA-SNEDDS-DP had protective effect on acute myocardial ischemia injury.

[Preparation and quality evaluation of volatile oil from Acori Tatarinowii Rhizoma self-nanoemulsion]

In order to increase the solubility of volatile oil from Acori Tatarinowii Rhizoma, this study was to prepare self-nanoemulsion of volatile oil from Acori Tatarinowii Rhizoma . The prescriptions were preliminarily screened by miscibility studies, excipient compatibility tests, and pseudo-ternary phase diagrams, and then the optimal formulation was obtained by using the Box-Behnken response surface method, with particle size and drug-loading rate as the indicators. The self-nanoemulsion prepared by optimal prescription was characterized and evaluated for in vitro dissolution. The results showed that the optimal prescription for this volatile oil self-nanoemulsion was as follows: 41.7% volatile oil, 46.8% Tween-80, and 11.5% PEG-400. The prepared self-nanoemulsion was clear and transparent, with drug-loading of (192.77±1.64) mg·g⁻¹, particle diameter of (53.20±0.94) nm, polydispersity index of 0.230± 0.013, and Zeta potential of (-12.2±0.7) mV. The in vitro dissolution of self-nanoemulsion was higher than that of volatile oil. In this research, volatile oil served as the oil phase in self-nanoemulsion, so the prescription was simpler and the drug loading rate was higher. The prepared self-nanoemulsion complied with the relevant quality requirements, providing a reference for the preparation of volatile oil formulations.

[Preparation of isopsoralen loaded nanostructured carrier and its in vitro transdermal permeation characteristics]

To increase the permeation and retention of isopsoralen in skin, and improve its bioavailability.Isopsoralen loaded nanostructure liquid carrier (IPRN-NLC) was prepared by high pressure homogenization andoptimized by orthogonal experiment with the encapsulation efficiency, drug loading and average particle size as the evaluation indexes. The in vitro transdermal permeation of IPRN-NLC was evaluated by Franze diffusion cells.The results showed that solid-liquid lipid ratio of optimum IPRN-NLC formulation was 7∶3,drug-lipid ratio of 1∶30, 1% surfactant. Under these conditions, IPRN-NLC had an average encapsulation of （90.25±0.73）%,drug loading of （1.56±0.27）% and an average particle size of (305±1.57) nm.The in vitro transdermal permeation results showed that IPRN-NLC could increase the amount of IPRN permeated though skin, with 3 times of the epidermal retention as compared with IPRN solution. From the results we can know that the IPRN-NLC prepared by high pressure homogenization can improve the permeation andaccumulation of IPRN in the skin, with wide application prospects in the field of transdermal administration.