• 2019-07
  • 2019-10
  • 2019-11
  • 2020-03
  • 2020-07
  • 2020-08
  • 2021-03
  • br UveVis spectroscopy analysis br Lambda


    3.4. UveVis spectroscopy analysis
    Lambda 35 spectrometer was used to study the optical ab-sorption spectrum. Silver oxide nanoparticles sample was dispersed in distilled water to measure the Thapsigargin spectrum in the range of 300 nme1000 nm at room temperature. Calcination effect has studied by optical spectrum of silver oxide nanoparticles as shown in Fig. 4. As the colloidal particles reduce in size, blue shift in absorption band is observed. It is clearly seen from the spectrum that the maximum wavelength of absorption (blue shift) seen at 500 nm to 390 nm due to the calcination temperature at 800 C [18]. Graphs has shown the characteristic peak of silver at 400 nm corresponding to resonating oscillations by surface plasmon and inter band transitions correspond to broad band region indicated by the tail of UV region. The spherical shape of particles is implied by the single surface plasmon peak in the graph [19].
    3.5. Cellular absorption
    Fig. 4. UveVis spectrum of silver oxide nanoparticles.
    recorded between 24 and 26 h of time shown increasing trend in cellular uptake collected from 10 mg/mL-30 mg/mL of concentration of nanoparticles and homogeneity in the uptake line were inves-tigated at 40 mg/mL. The plot shows the absorbance vs silver oxide nanoparticles concentration (0e80 mg/mL). However, significant peak quantity in absorbance was recorded against 50 mg/mL Silver oxide nanoparticles dispersed solution. Our data match with pre-vious reported work [5]. Then steeply increasing trend in hepato-cellular uptake was found above 50 mg/mL concentration. Maximum cellular absorbance is at 50 mg/mL concentration and abruptly decline in absorbance. It is novelty of our work not such kind of trend was reported in previous published data [6]. After 45 h- 47 h, the optical density of silver oxide nanoparticles in HepG2 cell model shown sudden homogeneous/saturation trend in the absorbance line indicating the maximum absorbance into cells at concentration of 60 mg/mL.
    3.6. Photo toxicity analysis
    Fig. 6 showed the significant loss in cell viability when cells were labeled with 60 mg/mL concentration of silver oxide nanoparticles. After this concentration the resistance in cell viability loss was investigated. At optimal concentration (60 mg/mL) of silver oxide nanoparticles about 70% cell viability losses were recorded even in
    Fig. 3. EDX Spectrum for silver oxide nanoparticles at 800OC/24 h (Ag is indicated in black color and O in red color). 
    Fig. 5. (a) Shows the snapshot of HepG2 cell line cultured in MEM. (b) Shows the cellular uptake of nanoparticles into HepG2 cell line at different time of incubation.
    Percent Loss in Cell Viability 
    Loss in Cell Viability
    Fig. 6. Percent cell viability loss in HepG2 Cell viability.  6000
    ROS Fluorescence vs silver oxide nanoparticles Conc.
    RFluorescenceOS 3000
    silver oxide nanoparticles Concentrations (mg/mL)
    Fig. 8. ROS Fluorescence (a.u) for silver oxide nanoparticles exposed in vitro HepG2 Model.
    the absence of laser light. In the initial (0e40 mg/mL) cell viability loss was about 50%. This loss reaches to 70% by using 60e70 mg/mL of said solution. Many researcher reported that nonsignificant cell killing pattern of RD labeled with different concentrations of TF-59 were recorded as mentioned before (in case of 5-ALA), this loss in cell viability reaches to almost 30%. Some of the researchers agreed with this opinion that approximately 25% cell death might occur due to mechanical stress/trauma of the shape and configuration of different sizes of nanomaterials e.g. ZnO NRs, TF-200 NPs, TF-59 NPs can have ability of cell membrane rupture/trauma [11e16,20].
    3.7. Reactive oxygen species analysis
    After optimized dose of silver oxide nanoparticles concentration (from 0 mg/mL to 80 mg/mL) concentration, HepG2 Cells were incubated with CMH2DCFDA for tracing the actual cells killing mechanism via oxidative stress or reactive oxygen species. Signif-icant ROS fluorescence was depicted in Fig. 8. Similar kind of study 
    was already reported by F. shaheen et al. and S. Iqbal et al. [21,22] for detection ROS liberation in term of nanomaterial's exposed and their absence. The marvelous trend of rising fluorescence was found from 1000 a. u to 5200 a. u when the silver oxide nano-particles concentration increases from 0 to 80 mg/mL. Results depicted the excellent from of pattern with previous published data [ [23e26]. The results implement that after certain concentration of silver oxide nanoparticles depicts very toxic might be helpful for biomedical and clinical applications. In addition ROS fluorescence beard treated HepG2 cells revealed significant reactive oxygen fluorescence and necrosis form of treated HepG2 cells as when in ROS micrograph Fig. 7, where (a) shows ROS Fluorescence and (b) shows Necrosed cells treated with silver oxide nanoparticle having concentration of 60 mg/mL [27,28].