Electrochemical monitoring of colloidal silver nanowires in aqueous samples

Silver nanowires (NWs) are increasingly utilized in technological materials and consumer products, but an effective analytical technique is not yet available to measure their concentration in the environment. Here, we present an electrochemical method to quantify Ag NWs suspended in aqueous solution. Using linear sweep voltammetry, the Ag NWs are identified by the peak potential while their concentration is revealed by the intensity of the peak current. The peak current varies linearly with the Ag NW concentration with a low detection limit of 3.50 ng mL(-1). This method is also successfully applied to quantify Ag NWs in mixtures with nanoparticles, through their specific oxidation behavior, and in wastewater obtained after the Ag NW film preparation process.