An Atomic Force Microscopy Study of Riboflavin Receptor Targeting Nanoparticles

Abstract

Riboflavin ligands present an alternative pathway for targeted drug delivery as riboflavin receptors are over-expressed in breast and prostate cancer cells. We have examined a riboflavin conjugated PAMAM dendrimer (generation 5) for targeting riboflavin binding protein (RFBP), which acts as a model protein for the riboflavin receptor. By characterizing the binding interactions between riboflavin dendrimer gold nanoparticle conjugates and RFBP, the efficacy of this platform for a targeted approach of drug delivery can be predicted more accurately. Atomic Force Microscopy (AFM) was used for biological imaging studies of these riboflavin-dendrimer complexes conjugated with gold-nanoparticles. using a systematic “building block” approach, the size distribution of riboflavin dendrimer gold nanoparticle conjugates was mapped. Changes in height upon binding to RFBP and subsequent removal by competitive binding ligands demonstrate that this method could present a novel approach to screening the binding of drugs to drug targets.