24.5 Applications of Biosynthesized Nanoparticles

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To confirm the composition of the nanoparticle, energy dispersive X-ray (EDX)

is suitable. EDX is coupled with SEM and TEM devices. The X-ray emitted is the

unique characteristic for an individual element. The EDX spectrum provides pres-

ence of different elements in the sample. Purity of the synthesized nanoparticles can

be determined based on the composition.

24.4.5

X-ray Diffraction (XRD)

The X-ray diffraction technique is basically used to determine the crystal structure

and lattice parameters of the given material. The crystallinity and amorphous

nature of the material can be identified through X-ray diffraction (XRD) patterns.

The sharp peak corresponds well to crystalline material and amorphous materials

do not exhibit sharp peaks.

24.5

Applications of Biosynthesized Nanoparticles

24.5.1

Antimicrobial Activity

Most of the metal nanoparticles are reported to exhibit antimicrobial activity.

Nanoparticles synthesized using agriculture and horticulture material can be

evaluated for the antimicrobial activity using either disc diffusion or perforated

well method. For representing the same, the gram positive and negative bacteria

are cultured separately. These cultured bacteria can be used for performing the

inhibition activity as described below:

a. To evaluate the antibacterial activity using disc diffusion method, a bacterial

lawn is cultured in the petriplate. A clean sterilized paper disc dipped in colloidal

solution of nanoparticle is taken and is placed in the bacterial lawn along with

the control disc. A zone of inhibition is achieved after preferably 24–48 hours.

b. In well diffusion method, previously grown bacterial culture plate is taken.

Appropriate wells are punched in the petriplates, and the colloidal solution

of nanoparticle at required concentration is added. The respective zone of

inhibition is evaluated after 24–48 hours.

24.5.2

Photocatalysis

Nanoparticles are reported to be a promising tool for the dye degradation application.

Photocatalysis can be carried out by mixing the required concentration of any dye

considered in the experimental protocol along with the biosynthesized nanoparti-

cles under natural sunlight condition for any fixed duration of time. In continuation

with the said protocol, the absorbance of the dye can be measured at different inter-

vals of time using UV visible spectrophotometer at its characteristic wavelength.

As the photocatalysis progresses further, the resultant absorbance of the solution

gets reduced. Thus, the percentage of photocatalysis can be calculated in compari-

son with control samples (without nanoparticles). Accordingly, photocatalysis under