All the biosensors showed an immediate response to H2O2. The effect of HRP/AuNP incorporated with CHIT (HRP/AuNP/CHIT/SPCE)
yielded the highest performance. The amperometric response of HRP/AuNP/CHIT/SPCE retained over 95% of the initial current of the 1st day up
to 30 days of storage at 4 ◦C. The biosensor showed a linear range of 0.01–11.3 mM H2O2, with a detection limit of 0.65 M H2O2 (S/N = 3). The
low detection limit, long storage life and wide linear range of this biosensor make it advantageous in many applications, including bioreactors and
biosensors.