Determination of isoniazid using mercury(II) ion selective membrane electrode

A Hg-II ion selective membrane electrode was fabricated using mercury-8-hydroxyquinolate as an electroactive material and PVC as an inert binder. The electrode gave linear response in the concentration range 1 x 10(-1)-1 x 10(-5) mol dm(-3) of Hg-II ions. The working pH range was 3-10 and the response time was 20 s. The electrode was selective for Hg-II ions in the presence of number of cations such as Ba-II, Ca-II, Cu-II, Ni-II, Co-II, Pb-II, Cd-II, Zn-II and Mn-II. In the present work, the isoniazid ammonium vanadate complex was also investigated using spectrophotometry so that these determinations could be compared with the values obtained from electrochemical sensor.