Amine-Functionalized Graphene Quantum Dots Conjugated with Amphotericin B: Synthesis, Characterization, and In Vitro Evaluation for Visceral Leishmaniasis Treatment

Abstract

Visceral Leishmaniasis (VL) is a life-threatening parasitic disease primarily affecting populations in resource-limited, endemic regions. Existing treatments for VL face limitations such as toxicity, high costs, and suboptimal efficacy in specific patient groups. Given the lack of a vaccine, chemotherapy remains the only option, emphasizing the urgent need for safer and more effective treatments. Nanotechnology offers promising avenues to overcome these challenges. This study introduces a novel approach involving amine-functionalized graphene quantum dots (fGQDs) conjugated with Amphotericin B (fGQDAmB) to enhance targeted drug delivery to Leishmania-infected macrophages. This novel approach, which could lead to a safer and more effective treatment for VL, is a significant contribution to the field. Structural characterization by XRD and FTIR confirmed successful GQD synthesis and functionalization, while cellular assays demonstrated significantly higher macrophage uptake and enhanced antileishmanial efficacy. fGQDAmB demonstrated approximately 4.2-fold greater potency against intracellular amastigotes and 2-fold higher efficacy against promastigotes, while also exhibiting reduced cytotoxicity compared to conventional AmB. The safety and effectiveness of fGQDAmB were further validated through hemolysis assay, providing reassurance and confidence about its potential use and instilling confidence in the potential of Quantum Dot-based Nanomedicine formulations. © 2025 The Authors. Published by American Chemical Society.