Protein-Templated Near-Infrared Emitting Fe Nanoclusters Exhibit Superparamagnetism at Room Temperature

Abstract

Water soluble Fe nanoclusters in the size ranging from 1.4 to 5 nm, exhibiting photoemission in the visible $(\lambda_{\text{em}}=450\ \text{nm})$ and near-infrared region $(\lambda_{\text{em}}=845\ \text{nm})$ have been synthesized with the use of mixed proteins. The protein-templated Fe nanoclusters exhibit superparamagnetism at room temperature, offering potential applications in bio-labeling and imaging.