Immobilized 2-(4-hydrazinocarbonylphenyl)-4,5-diphenylimidazole as solid phase luminophore in peroxyoxalate chemiluminescence

A new luminophore for application in peroxyoxalate chemiluminescence is presented. An analogue of the well-known chemiluminescence compound lophine, i.e. 2-(4-hydrazinocarbonylphenyl)-4,5-diphenyl-imidazole (HCPI), has been covalently immobilized to controlled pore glass and a porous methacrylate resin. By using this reagent in a solid phase detection reactor, sensitive determinations of hydrogen peroxide have been demonstrated. In homogeneous solution HCPI emits poorly as a result of 1,1'-oxalyldiimidazole excitation, but when immobilized its efficiency is almost comparable to highly efficient luminophores such as 3-aminofluoranthene. Linearity extends in the single stream flow system over several orders of magnitude with both materials. The limit of detection was 1 nmol/l (10 fmole injected), when using the porous methacrylate support.