Surface modification of cuprous oxide nanoparticles with improved chemical stability and antibacterial activity

Cuprous oxide (Cu2O) has been widely used as antibacterial agent due to its low cytotoxicity, low cost and outstanding antibacterial effect. However, the poor chemical stability of Cu2O has restricted its application. Herein, we report a simple surface modification method to improve not only the chemical stability but also the antibacterial performance of Cu2O nanoparticles. By modifying Cu2O nanoparticles with catechol (CAT) and tetraethylenepentamine (TEPA) in an aqueous solution at room temperature, core-shell structured Cu2[email protected] nanoparticles have been obtained. The chemical stability of Cu2O against heat and oxygen has been largely improved due to existence of the CAT-TEPA shell. More importantly, the modified nanoparticles show enhanced antibacterial performance. Similar phenomena have also been found by modifying Cu2O nanoparticles with other analogues like dopamine and tannic acid, and a possible mechanism was proposed. Application of Cu2[email protected] nanoparticles in the preparation of antibacterial membrane has been demonstrated. This simple and environmentally benign approach to improve both antibacterial performance and chemical stability of Cu2O will promote its practical application in many fields.