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Journal of Photochemistry & Photobiology, B: Biology
journal homepage: www.elsevier.com/locate/jphotobiol
Biosynthesis of sorafenib coated graphene nanosheets for the treatment of T gastric cancer in patients in nursing care
Xiaoyue Xua, Xiaoyu Tangb, Xiaoxu Wuc, Xiufang Fenga,
a The Third Department of Tumor Surgery, Tangshan Gongren Hospital, People's Republic of China b Department of Rehabilitation Medicine, Tangshan Gongren Hospital, People's Republic of China c The Department of Radiology, Tangshan Gongren Hospital, People's Republic of China
Sorafenib (SRF) is a well-known tyrosine kinase inhibiting anticancer drug which iseffectual against multiple carcinomas especially gastric cancers by targeting the Ras/Raf/Mek/Erk cascade pathway and blocking the tumor cell proliferation. In the present work, we have reduced graphene oxide (GO) in presence of sorafenib using ascorbic as green reducing agent for the treatment of gastric cancers. Sorafenib reduced graphene oxide (SRGO) were obtained with a transparent and smoothmorphology. The drug loaded SRGO has presented sig-nificant cytotoxic effect against SGC7901 cancer GS 9620 when compared to that of the free SRF and blank NPs in the equivalent concentrations. Additionally, from the Hoechst 33382 staining study it was evident that the cells in untreated groups remained intact with its round shape and intact nuclei while the SRGO treated cells have shown a cell transformation with apoptosis of gastric cancer cell lines. Based on these results, we can conclude that SRGO might extend an enormous prospective in the treatment of gastric cancers.
In the recent times, graphene has significant potential with wide range of biomedical applications . Graphene oxide (GO) comprises of carbon monolayer with epoxide and hydroxyl functional groups on the accessible sides and carboxylic atoms packed to formdense honey comb lattice structure. GO formed due to oxidative exfoliation of gra-phite consist huge amounts of residual carboxylic acid, hydroxide groups, and epoxide which could affect the hydrophilicity along with other functional and structural properties of nonmaterial. Therefore, reduction of these residual functional groups facilitates in the en-hancement of several properties of GO. Among various properties that contribute towards biocompatibility like size, number of layers, shape, charge on surface of nanomaterials, surface chemistry plays a vital role in the determination of biocompatibility and controlling behaviour of nanomaterials within the biological systems . However, pristine GO was found to possess immense significance in the formation of anti-microbial surfaces in solar cells [3,4].
Reduced graphene oxide (RGO) results from the treatment of GO with reducing agents RGO displays enhanced electrical conductivity and can be simply improvised with hydrophilic functional groups for making use in biomolecule functionalization [5–9]. Previous research
on cytotoxicity of RGO in contrast to GO has presented that RGO has minimal toxicity when compared to GO, which might be attributed to the presence of more number of reactive functional groups (COOH, -OH, alkoxy, and C-O as epoxy)on the surface of GO which have sig-nificant potential to interact with biological macromolecules . Henceforth, reducing functional groups on the GO surface are the key factors in making them more appropriate for biological applications . Among various methods to reduce functionalities from GO surface like solvothermal reduction and thermal annealing [12–14], chemical reduction is being widely used for the large scale reduction of GO. However, hydrazine, Lawesson reagent, sodium borohydride, and thiourea are the most widely used chemical reducing agents [15,16]. In addition, some other reducing agents like anhydrous hydrazine and sodium borohydride are extremely harmful andtoxic to living en-vironment, thus other effective biological methods for GO reduction needs stringent investigation .
In order to overcome this challenge, biological methods are opted as the most considered alternative for reducing functionalities of GO. The use of biological resources in the nanoparticle synthesis has gained immense consideration because of their minimal energy requirement, environmental safety, commercial feasibility, reliability, and stability when compared with the chemical synthetic methods. Moreover,