Fabrication Of Three-dimensional Vesicle Network On Porous Membrane For Drug Screening

Recently,the level of drug research and development has been continuously improved with the development of technology.However,the cost of drug screening has been continuously increased.Because of the poor accuracy or the complex operation,common models can no longer meet the requests.Therefore,the models of drug screening with low cost and effective high-speed have become one of the research hotspots.In this thesis,vesicle aggregates on polycarbonate membrane were prepared to simulate “artificial tissue” for drug screening by electroformation.The vesicles were prepared on the non-conductive substrate-polycarbonate film/dialysis membrane by electroformation.When the electric field conditions were changed,the change of vesicle size was observed using a fluorescence microscope.The results showed that the average size of the vesicles would be larger with the larger AC voltage and the lower frequency.The average size of the vesicles formed on the dialysis membrane and the 3 μm polycarbonate membrane were 28.29 μm and 25.54 μm,respectively,with AC field of 125 Hz and 12 V.The field and size of vesicles were better in the aqueous solution than those in saline solution.By adding various fusion promoters before and after electroformation,the dispersed vesicles were formed into vesicle aggregates.The results showed that when biotin and avidin were used as fusion promoters,the formed vesicle aggregates were destroyed after a while,so they were not suitable for vesicle aggregates.However,poly-L-lysine is a suitable promoters,which could form stable vesicle aggregates no matter added before or after the electroformation.Two-electrode system with Ag/Ag Cl was used to measure the impedance of the artificial tissue.Doxorubicin(hydrophilic drug)and tetracycline(hydrophobic drug)were chosen to test the model.The results showed that the impedance of the system could meet the screening criteria of Caco-2 cell model after adding poly-L-lysine in 1 m M PBS.The effective membrane permeability values of doxorubicin and tetracycline were(5.19±0.51)×10-6 cm/s and(9.79±1.05)×10-6 cm/s,respectively.Those results confirmed the artificial tissue model formed after adding poly-L-lysine is suitable for drug screening.