The Pharmaceutical Research Of Total Glucoside Of Picrorhiza Scrophulariflora Lipsomes

Total glucoside of Picrorhiza scrophulariflora?TP?is main effective component of ridoids in Picrorhiza scrophulariiflora Pennell and Picrorhiza kurrooa Royle.In order to prolong the action time in vivo and enhance liver targeting effect,we selected to prepare it into total glucoside of Picrorhiza Scrophulariflora lipsomes?TPL?which has not been reported yet.The main findings of this study were as follows:1.Documents research about sources,chemical constitution,pharmacological effects,clinical application and related preparations of Picrorhiza Scrophulariflora was investigated.Modern pharmacology studies show that it can protect liver and benefit bile,relieve cough and asthma,lower blood lipid,improve memory,and also has the effect of nanti-inflammatory and neuroprotection.2.An RP-HPLC method for determination of the content and entrapment efficiency?EE?of P-? was established,which was determined after the separation of free drug from liposome bySephadex G-50.The drug can be well separated with a good linear relationship in the range of 1.01-100.72 ?g/mL and the linear equation was Y=14.98X-8.8477,r=0.9996.The average recovery was 100.00%-101.74%and RSD of intra-and inter-day precision was both less than 2%.3.The Preparation of TPL was investigated by ethanol injection method,reverse phase evaporation method,film dispersion ultrasonic method,ether injection method and calcium acetate gradient method,respectively.The EE were 2.01%?17.66%?10.65%?2.52%?5.08%,respectively,thus reverse phase evaporation method was selected to prepare it.EE was taken as a major index to evaluate the factors of preparing temperature,pH values,ultrasonicating time,Ether/Water ratio?V/V?,mass ratio of PC to cholesterol,mass ratio of drug to PC,extrusion,frozen.As a result,mass ratio of cholesterol to PC,Ether/Water ratio?V:V?and mass ratio of PC to drug were proved to have a great influence on EE.The formulation and preparing technique of TPL was settled by orthogonal design based on former study.The optimal technique and formulation were as follows:PC?50 mg?and chol?30 mg?were dissolved in trichloromethane?9 mL?,and the solvents were removed under reduced pressure by a rotary evaporator at 30 ?.The lipids film was redissolved in anhydrous ether?6 mL?,then PBS of TPL?2 mL?was dropped slowly in the organic phase,in which the reversed phase vesicles will be formed.Stable emulsion of W/O was made with probe ultrasound at 0 ?,and the organic phase was removed under reduced pressure by a rotary evaporator again until a homogeneous lipid-in-water suspension was fonned.TPL with blue opalescence was prepared when the suspension was filtrated by microfiltration membrane of 0.45 ?m and 0.22 ?m respectively.4.Properties of TPL were evaluated.The content of two residual solvents of ethanol and Chloroform was proved to in accord with the pharmacopeia standard.TPL with optimized fomulation featured the encapsulation efficiency of?71.50±1.30?%,the P-? content?100.01±1.03?%,drug loading of?1.55±0.0038?%,and pH value of?6.72±0.02?;They were observed to hold the shape of spherical or ellipsoidal shape,with the mean size of?125.9±1.0?nm,PDI of?0.23±0.01?and Zeta potential of-?14.6±0.4?mV.The content of MDA was?0.053±0.0006??g/mg and hemolysis test was proved to be negative.Results indicated that TPL had a modest entrapment efficiency,and the Particle size as well as negative charge were in accord with the targeting demands for liver,which met the expectaion.5.TPL stability were evaluated via Influence factor test and accelatrated stability test.Results indicated tha TPL were vulnerable to light and high temperature and had a good stability when stored at low temperature sealed without oxygen.6.The in vitro release was evaluated by dialysis method.Results showed that drug in TPL release much more slowly than the free drug and the kinetics were both consistent with Hixcon-Crowell equation.7.HPLC was used to determine P-? concentration in plasma and tissues at different time after iv administration of TP and TPL.The pharmacokinetic processes in rats for the two preparation were both accorded with two compartmental models.Their eliminative half-life were?36.28±14.28?and?78.91±24.02?min,and AUC were?996.49±38.98?and?1890.12±308₈0?.The content of P-? in hearts,spleen,lung,kidney in TPL group were slightly higher while greatly higher in liver than that of injection group.The results demonstrated TPL can increase picroside ? distribution in most tissues and can prolong the action time,which would decrease the administration dose and reduce adverse effect.8.After iv administrated TP solution and TPL to mice,respectively,the drug concentrations in different tissues were monitored by HPLC.The content of P-? of TPL group in spleen and kidney were slightly higher than that of solution group.However,the concentration of drug in liver increased greatly compared with that of solution group.The result indicated that liver targeting index could be enhanced when TP was prepared into TPL.