Banaras Hindu University

About: Banaras Hindu University is a education organization based out in Varanasi, Uttar Pradesh, India. It is known for research contribution in the topics: Population & Dielectric. The organization has 11858 authors who have published 23917 publications receiving 464677 citations. The organization is also known as: Kashi Hindu Vishvavidyalay & Benares Hindu University.

Colorimetric detection of cholesterol based on highly efficient peroxidase mimetic activity of graphene quantum dots

Abstract: In the present study, we report graphene quantum dots (GQDs), an enzyme mimetic of horse radish peroxidase (HRP), for unprecedented detection of free cholesterol. Synthesized directly from graphite using simple and quick one step wet chemical method, these GQDs in the presence of H 2 O 2 exhibit highly efficient catalytic activity toward the oxidation of peroxidase substrate 3,3,5,5-tetramethylbenzidine (TMB) to produce a blue colored product. The proposed detection system based on GQDs allows wide range (0.02–0.6 mM) of cholesterol sensing with a detection limit as low as 0.006 mM. Further, higher V max (7.3 × 10 −6 M s −1 ) along with lower K m (0.01 mM) attest enhanced peroxidase like catalytic activity and better binding affinity of cholesterol oxidase (ChOx) to cholesterol resulting in good biosensor stability and resistance to environmental interferences. The proposed method without the use of sophisticated instruments perceives the cholesterol using naked eye with blue color compound formation. The potential of the method to be applied on field is shown by the proposed cholesterol measuring color wheel, where the shades of color are related to actual levels of cholesterol in the sample.