▎ 摘　　要

NOVELTY - The variable voltage-based strip sensor comprises sample inlet unit that is provided to form a channel (11) through which a sample can be introduced and passed. The alternating current (AC) voltage passes to the sample through the channel. A sensing electrode unit detects the heavy metal ions contained in the sample introduced through the sample inlet (10). A cover portion covers the exposed portion to insulate the sample inlet portion and the sensing electrode portion. The sensing electrode unit has a working electrode (21) for detecting the presence and concentration of heavy metal ions by measuring a potential difference of the sample introduced through the sample inlet. The heavy metal ions are selected from the group consisting of cadmium, lead, mercury, and copper. THe graphene oxide or reduced graphene having a nano size is coated on the electrode. USE - Variable voltage-based strip sensor for detecting heavy metal ions in aqueous solutions. ADVANTAGE - The sensor ensures simultaneous detection of heavy metal ions and selective detection without interfering effects of other active species. DESCRIPTION OF DRAWING(S) - The drawing shows a schematic view of the variable voltage-based strip sensor. Sample inlet (10) Channel (11) Alternating current voltage (12) Working electrode (21) Reference electrode (22)