**2. Experimental**

## **2.1 Synthesize of the novel nanomaterials**

### *2.1.1 Graphdiyne*

The synthesis of the GDY was reported in the literature as follows:

Graphdiyne (GDY) was prepared on the copper surface by a cross-linking reaction using hexaetynylbenzene (HEB) as a monomer. Firstly, hexakis [(trimethylsilyl) ethynyl] benzene (HEB-TMS) was prepared using Negishi cross-linking reaction. Then HEB monomer was obtained by the addition of tetrabutylammonium fluoride into tetrahydrofuran solution of HEB-TMS with stirring at 0°C for 10 minutes. Finally, GDY in the presence of pyridine was successfully grown on the surface of copper foils by a cross-coupling reaction of the HEB monomer for 72 hours at 60°C under a nitrogen atmosphere. After the reaction was completed, GDY grown on copper foils was removed by ultrasonic treatment and concentrated by rotary evaporator, and then washed with heated acetone and N,N-dimethylformamide. The GDY powder was refluxed with dilute hydrochloric acid and sodium hydroxide, respectively at 80°C for 3 hours. It was then washed repeatedly and centrifuged. Finally, black GDY powder was obtained by centrifugation and drying vacuum [8].

#### *2.1.2 Gold nanostructures*

According to the modified El-Sayed method the synthesis of the gold nanorods (GNRs) was performed as follows:

Ttwo solutions were prepared as seed solution and growth solution. For the seed solution, ice-cold sodium borohydride (NaBH4) (0.3 mL, 0.01 M) was added to the solution mixture containing hydrogen tetrachloroaurate (HAuCl4) (0.5 mM) and cetyltrimethylammonium bromide (CTAB) (0.2 M) in a volume ratio of 1:1, and the entire reaction mixture was incubated at room temperature for 3 hours. For the growth solution, a 200 mL solution containing HAuCl4 (0.5 mM) and CTAB (0.1 M) was made and 6 mL of silver nitrate (AgNO3) (4 mM) was added to it. Following this, 0.5 M sulfuric acid (H2SO4) (1 mL) and 0.0788 M ascorbic acid (1.4 mL) were

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*The Novel Nanomaterials Based Biosensors and Their Applications*

this section as one of the inorganic nanomaterials.

powder was dried in an air oven at 50°C [10].

added and mixed gently. In the last step, the seed solution (0.24 mL) was added to the growth solution mixture and left at room temperature for a period of 12 hours. The brownish colored solution was centrifuged at 9000 rpm (2 times) for 30 minutes

The synthesis of Zirconium Phosphate Nanoparticle (ZrP-NP) is described in

The synthesis of the core-shell Au@Co-Fe hybrid nanoparticles is described as

In the synthesis of the core-shell Au@Co-Fe hybrid nanoparticles as the peroxidase mimetic nanozyme, gold nanoparticles (AuNPs) with the average diameter of 22 nm were synthesized by citrate reduction of HAuCl4. Briefly, 1.5 mL of 1% (w/v) sodium citrate solution was added to 21 mL of 0.8 mM HAuCl4.3H2O solution at boiling point while the solution was stirred vigorously. After hanging its color from pale yellow to deep red, the mixture was stirred for 15 min and let to cool to room temperature and, then stored at 4°C until use. In the second step, 1 μL tween 20 was added to 1.5 mL of the synthesized AuNPs. Then, 100 μL of FeSO4 0.18 M and 180 μL of CoCl2 0.1 M were added to the mixture, and incubated at the room temperature for 24 h. After that, the mixture was centrifuged and washed with

One of the hybrid nanocomposites is reduced graphene oxide-magnetite nanoparticle (RGO-Fe3O4 NP) and its synthesis is described below according to the

Reduce graphene oxide magnetite nanoparticle (RGO-Fe3O4 NP) hybrid was synthesized by alkaline reduction. For this purpose, the powder was redispersed in the 0.5 mg mL−1 graphene oxide (GO) suspension. Citric and ascorbic acids were added and the mixture was stirred at 55°C (12 hours). 1 M NaOH was added and the mixture It was stirred again at 95°C (6 hours). After centrifugation at 10000 rpm (RCF = 1118 x g), the solid is filtered, washed, and dried in vacuum during

Y-DNA was prepared by mixing equimolar amounts of three single stranded DNA (ssDNA), two long and one short. The two long sequences have regions that hybridize to the shorter one. One of the fields is not completely linked to the corresponding fragment. Thus, the target miRNA became able to replace this fragment

Zirconium Phosphate (ZrP), one of the inorganic nanomaterials, has been synthesized by hydrothermal process. First, 1.6 g of ZrOCl2.8H2O was added to 30 mL of DI water and stirred continuously. Then 15 M H3PO4 (10 mL) was added to this prepared solution and stirred continuously for 30 minutes. The solution was transferred to a hydrothermal autoclave (50 mL) and heated in an air oven at 200°C for 24 hours. The products obtained were collected by centrifugation and washed several times with ethanol and deionized water. In the last step, the purified ZrP

to remove unbound CTAB and stored at room temperature (28°C) [9].

*DOI: http://dx.doi.org/10.5772/intechopen.94930*

*2.1.3 Inorganic nanomaterials*

*2.1.4 Nanozymes*

deionized water [11].

literature [12].

24 hours [12].

*2.1.6 DNA nanomaterials*

*2.1.5 Hybrid nanocomposites*

peroxidase mimetic nanozyme.

added and mixed gently. In the last step, the seed solution (0.24 mL) was added to the growth solution mixture and left at room temperature for a period of 12 hours. The brownish colored solution was centrifuged at 9000 rpm (2 times) for 30 minutes to remove unbound CTAB and stored at room temperature (28°C) [9].
