Design,Preparation And Properties Of Surfactant Materials With Drug-Loading Capacity

Silicone surfactants possess excellent ductility,strong adhesion,high porosity permeability,high and low temperature resistance,non-toxic,physiological inertia and biocompatibility and other excellent properties,and are widely used in textile,paint,plastics,oil extraction,agricultural chemicals,cosmetics,medicine,protein and polyurethane industry and other fields.Silicone surfactants mainly includes trisiloxane surfactants,polyether modified silicone surfactants and other silicone surfactants,in which polyether modified silicone is a class of biocompatible amphiphilic copolymer and could be applied in the field of drug carriers.In this paper,five kinds of polymer silicone surfactants were prepared and their self-assembly behavior was studied.The drug loading ability of the drug carrier was explored.The main contents are as follows:1.The polysiloxane and the polyether were blocked and grafted in two forms by the addition reaction of hydrosilylation,and then the terminal hydroxyl group of the polyether segments were modified by the quaternization method to give two cationic surfactants:polyethylene glycol polydimethylsiloxane triblock quaternary ammonium copolymer(QAC-PEG-b-PDMS-b-PEG-QAC,bPP-QAC in short)and polyethylene glycol grafted polydimethylsiloxane quaternary ammonium copolymer(PDMS-g-PEG-QAC,gPP-QAC in short).FT-IR,'H NMR,13C NMR and gel permeation chromatography were used to characterize and determine the structure of the final product.The methylation blue transfer assay and the determination of conductivity and zeta potential verified their positive charge.The experimental results showed that the two cationic silicone surfactants bPP-QAC and gPP-QAC owned lower critical micelle concentration(CMC).The results of dynamic light scattering(DLS)and transmission electron microscopy(TEM)showed that they could self-assemble into stable nanoparticles in aqueous solution with narrow size distribution,and the particle sizes were 67 nm and 104 nm,respectively and will be a slight increase after loading drugs.The drug laoding and in vitro release studies showed that bPP-QAC owned high drug loading contents(DLC)and drug loading efficiency(DLE)of 15.6%and 78.0%,respectively,and the cumulative release ratio was 54.9%in 48 h.While the DLC and DLE of gPP-QAC were relatively low,2.1%and 10.3%respectively,and the cumulative release ratio was 66.8%in 48 h.Compared with the block copolymers,gPP-QAC owned much more proportion of polyether,because of the strong affinity between the PEG segments and water,the hydrophobic core of the nanoparticles formed from gPP-QAC was more loose,resulting in weak interaction force between PDMS segment and tocopherol and low drug-loading capacity.2.A series of non-ionic amphiphilic surfactants polyethylene glycol polydimethylsiloxane triblock copolymers(PEG-b-PDMS-b-PEG,PP1,PP2 and PP3 in short)were prepared via novel metal-free click reaction successfully.TF-IR,1H NMR and gel permeation chromatography were used to demonstrate their exact structures.Their self-assembly behavior in aqueous solution was studied by using pyrene fluorescence probe method,dynamic light scattering and transmission electron microscopy.The results showed that the surfactants possessed low CMCs,which were increased with the increase of PDMS length.The surfactants can self-assemble into vesicle-like nanoparticles with particle size from 127 nm to 172 nm,and the particle size and wall thickness of the vesicle-like nanoparticles increase with the increase of the length of PDMS.The encapsulation and release performance of vitamin E was investigated and the results showned that PP1,PP2 and PP3 all exhibited good drug capacity and the release ratio were all more than 60%.Thereinto,PP1 was the best and the DLC and DLE were 17.7%and 88.5%respectively,while PP3 was lower because it could not form a complete vesicle-like aggregates due to the very long PDMS.Finally,the thermal stability of the materials was evaluated by thermogravimetric analysis.The results showed that the initial decomposition temperature of the three surfactants was above 310? with good thermal stability.