Benzoylthiourea based polymers as new binding agents for diffusive gradients in thin films technique in labile mercury determination in freshwaters

In this study, the diffusive gradient in thin film (DGT) has been developed using three new materials derived from benzoylthiourea (PBTU, BTP1 and BTP2) for determination of bioavailable mercury (Hg). The efficiency these DGT devices was compared with well-established 3-mercaptopropyl functionalized silica gel (3MFS) laboratory field conditions. It found that PBTU lacked consistency handling assembling device, whereas other two polymers provided mechanically stable binding gels extracted satisfactorily Hg. However, BTP2 showed no correlation between Hg uptake present aqueous solution, therefore, chosen as layer used technique. calculated diffusion coefficient DGT-BTP1 4.0 × 10 −6 cm 2 s −1 at 25 °C 0.8 mm thick 2.3% w/v material gel, DGT-3MFS, D value 9.1 . Moreover, it neither pH (range 4.5 – 9.5) nor ionic strength 0.005–0.1 mol L ) significantly affected behavior (p > 0.05). Finally, were successfully in-situ measurements Quito River (Colombia), impacted by artisanal gold mining, DGT-3MFS. Results a good performance values labile concentration 5 to 8% total water. This study demonstrates based is useful tool situ monitoring freshwaters. • Three Hg, suitable solutions wide range. These Colombian river highly Benzoylthiourea