Zirconium phosphate-methylene blue composite immobilized at room-temperature ionic liquid matrix for electrochemical detection of NADH

Electroactive methylene blue (mb) entrapped in α-zirconium phosphate (zrp) were first synthesized by a simple chemical method. room-temperature ionic liquid (il) was used as a matrix to immobilize zrp-mb composite on pyrolytic graphite (pg) electrode and the resulting modified electrode can be utilized in electrocatalytic oxidation of nadh. because of the combination of the excellent electroactivity of mb,the good chemical and mechanical properties of zrp and the good ionic conductivity of il,the response current of nadh at pg/zrp-mb/il electrode is much larger than that in bare and zrp-il electrode and the interference of ascorbic acid can be avoided efficiently. the pg/zrp-mb/il electrode displayed high sensitivity (76.5 ma m-1 cm-2),low detection limit (6 μm),fast response time (within 5s) and wide linear range (6-540 μm).