A benzothiazole-based receptor-immobilised silica nanoparticle as chemosensor for Hg²⁺

Abstract

<div><p>Fluorogenic benzothiazole-based receptor has been easily immobilised onto filter paper and silica nanoparticle by sol-gel reaction. The sensing ability of the benzothiazole-immobilised thin layer filter paper chromatography (<b>TLC-1</b>) was evaluated on the basis of fluorescent changes caused by metal ions that were dropped onto the TLC plate. The <b>TLC-1</b> exhibited a high affinity and selectivity for Hg²⁺ over other competing metal ions. Therefore, the <b>TLC-1</b> holds promise as a portable sensor for the detection of Hg²⁺ in aqueous solution. Furthermore, the adsorption capacity of a column packed with <b>SiO</b>_<b>2</b><b>-1</b> was evaluated by the application of metal ions under various experimental conditions, such as pH, flow rate and concentration. The <b>SiO2-1</b> column removed 98% of Hg²⁺ from drinking water containing 10 ppb of Hg²⁺. The adsorption capacity of the <b>SiO</b>_<b>2</b><b>-1</b> column was not strongly affected by pH and flow rates.</p></div