The Study Of Liposomes For Transdermal Delivery Of Brucine

In recent years, the liposomes for the treatment of transdermic absorption is a focalpoint in the research of external preparation. The present research has indicated liposomesis a good carrier in transdermal delivery, which can reduce the toxicity and side effect ofdrug and has the effect of slow release and prolonged action. Take orally and externallyapplication is the traditional usage of Strychnos nux-vomica L. Transdermal delivery ofStrychnos nux-vomica L. preparation has been proved to be the effective way in treatmentfor rheumatic arthritis, prosopoplegia, cancer pain and so on. But because of the largetoxicity, it is necessary to control the transdermal delivery. Presently, the spraying agent ofbrucine liposome has been applied in treatment for rheumatoid arthritis in clinic, but theliposome has existed the disadvantage of low encapsulation efficiency and high cost.Therefore, take brucine for the study object, which is the mainly drug action and toxicitycomponent of Strychnos nux-vomica L., we prepare the brucine liposome of lowencapsulation efficiency and high cost and use it in transdermal delivery to achieve thedestination of controlling release, enhancing curative effect and reducing toxicity. Also, weplan to use new technology as combination phospholipid lipsome to elevate its drugconcentration and study its effect on the rate of transdermic absorption in order to establishthe foundation of the correlation research between the rate and the drug action intransdermic absorption in the future.The article has determined the physico-chemical property of brucine, such as theoil-water partition coefficients. Through considering any influential factors on transdermaldelivery, it has established the feasible research method on transdermic absorption ofbrucine.In order to control the quality of liposome, the article has established the methods fordetermination of the brucine concentration in liposome by UV-spectrophotometry andencapsulation efficiency by sephadex gel filtration chromatography-UV, which coulddetermine them accurately. The article has investigated the preparation prescription andtechnological factors to elevate the brucine concentration in liposome. The single factor is inspected such as the dosage of phospholipid and cholesterol, the volume of ammoniumsulfate, the method of control particle and the temperature of incubation to optimize theprescription technology. The brucine liposome prepared by the optimal technology hasremarkable enhancement in the medicine concentration, which can reach 1mg/ml and theencapsulation efficiency is 88.07％. Simultaneously, the temperature has reduced in theoptimal prescription technology to enhance the stability of lipsome.The article has investigated the effect of the different administrations in transdermaldelivery of brucine liposome. The results has showed that administrations has a big effecton transdermal delivery. The rate of the occlusive system and the nonocclusive one are(0.23±0.04)μg/cm~2/h and (0.41±0.10)μg/cm~2/h. It has hinted that the rate of thenonocclusive system is obviously faster than the occlusive one. The article also hascompared the analgesic effect between the brucine solution and brucine liposome. Theresult has showed that liposome can remarkably enhance the analgesic effect of brucineusing the external skin(P＜0.01). It has provided the evidence to adoption liposome fortransdermal delivery of brucine.The article has investigated the effect of phospholipid composition on brucineliposome quality. The chemicophysical properties were compared among brucine soybeanphospholipid liposome, brucine hydrogenated soya phosphatide liposome and brucinecombination phosphatide(SPC/HSPC=1∶1) liposome, like particle size and electricpotential. The results showed that the particle size of three kinds of liposome are 178.8nm,286.9nm, 162.3nm. The zeta potential is 4.5mV,-18.5mV,9.0mV. It means that thephospholipids composition has the certain but not significant influence in the particle sizeand the zeta potential. Meanwhile, we has done the preliminary research on dependabilitybetween phospholipids composition and concentration. The results showed that theconcentration of combination phosphatide is obviously higher than single phosphatideliposome. When the dosage of phosphatide is fixed and the SPC/HSPC is 9∶1, theliposome concentration is 3mg/ml, and the encapsulation efficiency is 81.83％. Theproportion of phospholipids composition has a prominent effect on liposome concentration.When he dosage of phosphatide is fixed and the SPC/HSPC is between 9∶1 and 1∶1, thepercentage of SPC has a direct correlation with the liposome concentration.The article has investigated the effect of the rate in transdermic absorption with thedifferent phospholipids composition. The results has indicated that when the concentrationis 1mglml, the rate of transdermic absorption by brucine soybean phospholipid liposome and brucine combination phosphatide (SPC/HSPC=1∶1) liposome are (0.38±0.15)μg/cm~2/h and (0.87±0.34)μg/cm~2/h. And when the concentration is 1.5mglml, the rate ofthe different phospholipids composition, which SPC/HSPC=1∶1 and 9∶1, are(1.39±0.61)μg/cm~2/h and (0.45±0.22)μg/cm~2/h. Through the results, we can concludethat the rate of transdermic absorption of the brucine combination phosphatide is obviouslyfaster than the brucine soybean phospholipid liposome. And it can control the proportion ofSPC/HSPC in combination phosphatide to regulate the rate in transdermic absorption.