Photocatalytic Degradation of Methylene Blue and Metanil Yellow Dyes Using Green Synthesized Zinc Oxide (ZnO) Nanocrystals

In this work, ZnO nanocrystals (NCs) have been effectively synthesized by a simple, efficient and cost-effective method using coconut husk extract as a novel fuel. The synthesized NCs are characterized by UV-Vis, XRD, FT-IR, SEM, EDX, Raman and PL studies. The obtained ZnO were found to be UV-active with a bandgap of 2.93 eV. The X-ray diffraction pattern confirms the crystallinity of the ZnO with hexagonally structured ZnO with a crystallite size of 48 nm, while the SEM analysis reveals the hexagonal bipyramid morphology. Photocatalytic activities of the synthesized ZnO NCs are used to degrade methylene blue and metanil yellow dyes.

Detection and Estimation of Metanil Yellow & Congo Red: Carcinogenic Food Colourants, Present in Different Food Samples

Nowadays adulteration is a social disease which is applied on food to make food more attractive and to gain more profit from it. Along with different processed food products, Spices like Turmeric powder, red chilli powder, etc. provides good nutrition to us until they are treated with some foreign colours or organic colours to make them adulterated, which causes various detrimental effects in physiological system such as heart failure, liver damage, cancer and many more, if people consume them over a certain period of time. Metanil yellow, Sudan red dye, Congo red are such organic dyes which are used abundantly in different spices and processed food products. These dyes are toxic chemicals and could be carcinogenic as well. The presence of all these components can be detected with chemical experiments. This present research study is focused on the detection of adulterants present in sample on the basis of pH variation of adulterated food sample from the pure one and its estimation by variation of spectrophotometric absorbance with the concentration of the adulterant in the sample. After testing samples with different concentration of adulterants, it has been observed that pH of samples is gradually increasing with the increase in concentration of adulterants from 0 to 16.66 gm/100gm present in the sample.