Siddique Yasir Hasan, Fatima Ambreen, Jyoti Smita, Naz Falaq, Khan Wasi, Singh Braj Raj, Naqvi Alim Hussain
Drosophila Transgenic Laboratory, Section of Genetics, Department of Zoology, Faculty of Life Sciences, Aligarh Muslim University, Aligarh, Uttar Pradesh, India.
PLoS One. 2013 Dec 5;8(12):e80944. doi: 10.1371/journal.pone.0080944. eCollection 2013.
Graphene, a two-dimensional carbon sheet with single-atom thickness, have attracted the scientific world for its potential applications in various field including the biomedical areas. In the present study the graphene copper nanocomposite (GCNC) was synthesized, characterized and evaluated for its toxic potential on third instar larvae of transgenic Drosophila melanogaster (hsp70-lacZ)Bg(9) . The synthesized GCNC was analyzed by X-ray diffraction (XRD), scanning/transmission electron microscopy (SEM/TEM), atomic force microscopy (AFM), and fourier transform infrared spectroscopy (FTIR). The GCNC in 0.1% DMSO was sonicated for 10 min and the final concentration of 0.033, 0.099, 0.199 and 3.996 µg/µl of diet were established. The third instar larvae were allowed to feed on it separately for 24 and 48 hrs. The hsp70 expression was measured by O-nitrophenyl-β-D-galactopyranoside assay, tissue damage by trypan blue exclusion test and β-galactosidase activity was monitored by in situ histochemical β-galactosidase staining. Oxidative stress was monitored by performing lipid peroxidation assay and total protein estimation. Ethidium bromide/acridine orange staining was performed on midgut cells for apoptotic index and the comet assay was performed for the DNA damage. The results of the present study showed that the exposure of 0.199 and 3.996 µg/µl of GCNC were toxic for 24 hr of exposure and for 48 hr of exposure: 0.099, 0.199 and 3.996 µg/µl of GCNC was toxic. The dose of 0.033 µg/µl of GCNC showed no toxic effects on its exposure to the third instar larvae for 24 hr as well as 48 hrs. This dose can be considered as No Observed Adverse Effect Level (NOAEL).
石墨烯是一种具有单原子厚度的二维碳片，因其在包括生物医学领域在内的各个领域的潜在应用而吸引了科学界的关注。在本研究中，合成了石墨烯铜纳米复合材料（GCNC），对其进行了表征，并评估了其对转基因黑腹果蝇（hsp70-lacZ）Bg(9) 三龄幼虫的潜在毒性。通过X射线衍射（XRD）、扫描/透射电子显微镜（SEM/TEM）、原子力显微镜（AFM）和傅里叶变换红外光谱（FTIR）对合成的GCNC进行了分析。将0.1%二甲基亚砜中的GCNC超声处理10分钟，并确定了饮食中最终浓度为0.033、0.099、0.199和3.996 µg/µl。让三龄幼虫分别以其为食24小时和48小时。通过邻硝基苯-β-D-半乳糖苷测定法测量hsp70表达，通过台盼蓝排斥试验检测组织损伤，并通过原位组织化学β-半乳糖苷酶染色监测β-半乳糖苷酶活性。通过进行脂质过氧化测定和总蛋白估计来监测氧化应激。对中肠细胞进行溴化乙锭/吖啶橙染色以测定凋亡指数，并进行彗星试验以检测DNA损伤。本研究结果表明，暴露于0.199和3.996 µg/µl的GCNC在暴露24小时时有毒性，在暴露48小时时：0.099、0.199和3.996 µg/µl的GCNC有毒。0.033 µg/µl的GCNC剂量在暴露于三龄幼虫24小时和48小时时均未显示出毒性作用。该剂量可被视为无观察到有害作用水平（NOAEL）。
