▎ 摘　　要

The astounding characteristics of the nanomaterials can be crafted to prepare tailor-made interfaces, especially for the development of biomedical applications. In the present study, we illustrate the preparation of a new class of doughnut-shaped manganese nanograins embellished on the graphene sheets to develop hybrid interfaces using a gentle and nontoxic approach. We investigate its potential to detect clinically important biomarkers and glutathione is chosen as a case study. The unprecedented structural morphology and chemical characteristics are described. Two-dimensional sheets of graphene are uniformly occupied by manganese nanograins. Each individual grain is doughnut-shaped with the external diameter of about 5-10 nm, the thickness of 2 nm with a small central cavity of about 1 nm. We show the unique morphology of hybrid offers conducting features of graphene, metallic nature of nanograins, and amelioration of greater surface area to promote enhanced binding capability. Resultantly, the hybrid yields remarkable sensitivity of 7 nM. A binding mechanism has been proposed along with extensive kinetics assessment. The developed hybrid can selectively bind glutathione in comparison of protein and non-protein molecules. The results validate that this approach can be used to design green hybrid materials for accurate diagnosis of biomarkers and metabolites. (C) 2020 The Authors. Published by Elsevier B.V.