Synthetically modified BSA-based heterometallic nanoparticles facilitating energy and/or electron transfer events

The variety of binding sites in BSA opens up possibilities for its use in developing systems with different functionality. However, the facile methods to develop co-loaded BSA nanoparticles (BNP) with luminescent and catalytic functions have not yet been fully explored. The luminescent lipophilic Pt²⁺ complex loaded into BNP via its outer-sphere binding to the hydrophobic regions of unfolded BSA serves as a luminescent probe to visualize the binding of Cu²⁺ ions followed by the Cu²⁺ → Cu⁺ reduction step and subsequent removal of these ions from BNP by glutathione. The specificity of luminescence and electrochemical behavior of co-loaded BNP reveals both a significant mutual influence of Cu(I) and Pt(II) centers and the influence of the co-loading method on these effects. The modification of the method allows changing the amount of copper ions per BNP, the luminescence of the complex and the laccase-like activity of copper ions bound to BNP. The latter activity was demonstrated using the oxidative conversion of adrenaline to adrenochrome. The above trends indicate that co-loading of redox-active copper ions and luminescent Pt(II) complex into BNP provides a route for combining sensing and catalytic activities, which can be tuned by modifying the synthetic method.