Biomedical Applications Of Graphene-based Nanocomposite Films

Graphene,a kind of carbon materials with single layer structure by six carbon atoms with sp2 hybrid orbitals.With particular structure and excellent properties,like high strength,good thermal and electron conductivity,ultralarge specific area,good biocompatibility and so on,recent years among fileds of catalysis,adsorption,sensing,electrode,and materials greatly drawn people's concern.Especially,it highlights many outstanding advantages in the application of multi-functionalized graphene among areas of biomedical domain and arises public great concern.In the paper,by means of layer-by-layer assembly technology,which prepared multilayers by alternately depositing of polyelectrolytes with the opposite charge,a series of graphene-nanoparticles composite ultrathin films in this paper have been constructed.In other words,interest in LBL technology root in advantages of this method,for example,the simple operation,the mild and controlled assembled conditions,and has no special requirement on the equipment,raw materials and substrate,so above the distinct merits facilitate exhibiting unique advantage in the design of biocompatible surface.Main work of this paper as follows.The first Chapter: Combined with layer-by-layer electrostatic assembly technique,positive charged PDDA-Prussian blue nanoparticles and negative charged glucose oxidase have been assembled on a glass carbon electrode to construct graphene-prussian nanoparticles glucose biosensors.Remarkable electron transfer rate of graphene improves the electrochemical activity of Prussian blue,achieves synergistic effect between graphene nanosheet and Prussian,thus hightens the electrochemical activity of Prussian and the performance of the sensor's electro-catalysis activity.Besides,via the electroreduction of H2O2 formed from enzymatic reaction made glucose determination more sensitive.The amperometric response exhibited a linear correlation to glucose concentration over a range from 0.1 to 6.5 mM,and the response time and detection limit were determined to be 2 s and 6 ?M,respectively.In addition,the biosensors also showed excellent anti-interference ability.Taking advantage of multi-functional self-assembly technology,advanced materials graphene and Prussian blue nanoparticles have been developed high performance glucose biosensor.The second Chapter: Photothermal therapy,a recently rising tumor therapy tool,upon light illumination,photothermal agents could convert optical energy to heat,thus the hyperthermia cause cancer cell thermal ablation,and it is a kind of noninvasive method.By this principle,in this part of work,based on good thermal performance of graphene and layer-by-layer assembly technique.So as to get a higher photothermal conversion efficiency composite materials in NIR region,we combined graphene with rod-shaped AuNRs nanomaterials and further used at cancer treat.The composite membranes fabricated here displayed well the synergy of graphene and gold nanorods,represented photothermal enhancement of AuNRs composites have been prepared successfully.Furthermore the series of composite films also be used as a thin-patch for the treatment of tumor located on near surface of skin.The results of cell and animals tests testified the multiple films expressed good tumor-killed effect.To establish a new type of high-efficiency and harmfulless cancer therapy method,this method provides a reference.The high effective noninvasive thin film patch will be expected to be used as a new generation of cancer diagnostic materials.