Graphene Advantages And Disadvantages 1x374d

Institute of Space Technology Assignment-3 MS&E-5

Biomaterials MSE-338

Submitted by: Sania Aman Roll # 120301041 1. Search the recent literature to find a paper/article on a novel biomaterial having innovative/unique applications. Give reference of the selected paper/article and (3) Ans: Graphene in Biomedicine: Opportunities and Challenges Liangzhu Feng; Zhuang Liu

A. Discuss the complex structure property relation of this biomaterial. (7) Ans: Graphene is made up of a single or few-layers sheet of Sp 2-bonded carbon atoms. scientists from various fields are interested in this 2D nanomaterial due to the unique physical and chemical properties.The most important property of graphene is its high electron mobility and its electrical properties that is dependant on size ,due to which it turns out to be an efficient material in high-performance electronic devices. graphene has light absorption in the range

from UV to near-infrared regions. It has also been found that

graphene oxide exhibits a size-dependent visible and NIR fluorescence. Due to the presence of largely dislocated π-electrons energy is allowed to transfer from the nearby molecules, which leads to remarkable fluorescence quenching that is useful in optical-based detection of biomolecules. Remarkable efforts have been devoted to fabricate large-area monolayered graphene with minimal defects via different possible chemical routes for applications in electronic devices and transparent conductors;whereas for biomedical applications of graphene in physiological environments, proper surface functionalization on graphene is needed to get high water solubility and biocompatibility. Both covalent and noncovalent strategies have

been studied

for graphene

functionalization. For the

non-covalent

chemistry, various molecules and polymers can be used to functionalize graphene via hydrophobic bindings or ϖ-ϖ interactions.For drug delivery as many aromatic drug molecules can be physically adsorbed on the polyaromatic graphene surface by ϖ-ϖ stacking, which usually takes place in the aqueous phase for less water-soluble drugs. In the last 2 years, there have been a large number of publications that report graphene-based

biosensors, mainly utilizing the unique chemical, optical, electrical and electrochemical properties of graphene.

B. Also document its limitations and propose strategies to overcome these. (5+5) The major limitation of graphene is the non biodegradable nature and its potential longterm toxicity. The preliminary results show that the physicochemical properties such as flat shape and charges, are closely related to the cytotoxicity, and affect in vivo bio distribution and fate of GO. The mechanisms of the in vitro biotoxicity caused by graphene are because of the oxidative stress and damage of cell membrane. In addition to this how exactly the sizes, structures and surface coatings of nano-graphene affect its in vivo behaviors, including tumor-targeting efficiency, reticuloendothelial system uptake levels and potential excretion, still remains unclear and further investigations is needed. Regarding graphenebased biosensing, a large number of publications have shown many exciting results in the last 2 years but still there is a need to fabricate, test and really confirm reliable, reproducible and low-cost sensors with high detection sensitivity and specificity. Another

challenge is

thorough and profound understanding of graphene-cell (or tissue, organ) interactions, especially the cellular uptake mechanism. Such knowledge facilitates development of more efficient graphene or GO-based nanoplatform for drug delivery, biosensing and other applications. A systematic study is highly desired to address the safety concerns before practical

applications

of

graphene

in

biomedicine..

to overcome

these

limitations

development of suitable chemical synthesis and functionalization approaches for precise control over size, size distribution, morphology, structural defects, and oxygen-containing groups of GO is needed, as this is closely correlated to the performance of the GO-based nanomaterials for biomedical applications, and the safety issues as well.