▎ 摘　　要

NOVELTY - The preparation method of electrochemical sensor involves preprocessing glassy carbon electrode and then mechanically polishing, drying using nitrogen and then activating, washing using deionized water and ultrapure water, adding 100 ml or 0.01-0.03 wt.% chloroauric acid solution and then heating for 10 minutes, adding 2-8 ml or 1-3 wt.% sodium citrate solution, continuously boiling for 10 minutes, cooling to room temperature, dissolving 1-5 g chitosan in 1-5 wt.% diluted acetic acid solution, adding 10-40 ml nano-gold solution, 0.03-0.15 g divalent cadmium ion and 1-5 ml graphene dispersion liquid, crosslinking using sodium tripolyphosphate solution for 1-3 hours, washing using acetone/water mixed solvent, placing in disodium edetate solution, eluting cadmium ion for 1-3 hours, washing using distilled water and drying. USE - The method is useful for preparation of electrochemical sensor, which is useful for detection of cadmium ions (claimed). ADVANTAGE - The method enables simple, easy and economical preparation of electrochemical sensor with high efficiency, selectivity and sensitivity and excellent stability and interference resistance in environmentally-friendly manner. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is included for electrochemical sensor prepared by the method.