*2.2.4. DNA oxidative biomarker*

Oxidative DNA damage caused by oxygen-free radicals lead to multiple modifications in DNA, including base-free sites and oxidized bases. The damage caused to DNA bases is potentially mutagenic [76] and can be enzymatically repaired. The interest lies in the sensitive determination and full characterization of the mechanism involved in oxidative damage to DNA bases. Electrochemical methods are used to study the DNA oxidative damage and in the investigation of the mechanisms of DNA-drug interactions. In recent study, it has been anticipated that the mispairs-coinage metal complexes can also be used as a biomarker [77].

**3.1. Carbon nanotubes (CNTs)**

based imaging.

**3.** Biosensing **4.** Optical [85]

**6.** Biomedical imaging

**7.** Molecular imaging [87, 88] **8.** MRI with SWCNTs [89, 90]

*3.1.1. Applications of CNTs in green electronics*

The various features of carbon nanotubes are:

**5.** Electronic and electrochemical sensors [86]

**9.** Optical imaging with SWCNTs [91, 92]

**11.** Photoacoustic tomography [95, 96]

**10.** Raman spectroscopy with SWCNTs [93, 94]

**1.** Drug delivery and cancer treatment [83] (**Figure 5**) **2.** Physical cancer therapies delivered by CNTs [84]

Carbon nanotubes (CNTs) are allotropes of carbon with a cylindrical nanostructure, a member of the fullerene structural family. Due to their extraordinary thermal conductivity, mechanical, and electrical properties, carbon nanotubes find applications as additives to various struc-

Biomolecules and Pure Carbon Aggregates: An Application Towards "Green Electronics"

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Single-walled carbon nanotubes (SWCNTs) also have unique properties which make them suitable for applications in a variety of imaging modalities, such as magnetic resonance, nearinfrared fluorescence, Raman spectroscopy, photoacoustic tomography, and radionuclide-

tural materials. The various representations of CNTs are given in **Figure 4**.

**Figure 4.** Representation of SWCNT and MWCNTs (armchair, zigzag and chiral).
